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Vulkanudbruddet har holdt sig relativt stabilt de seneste 24 timer

Vulkansk smog er blevet observeret i mange områder over hele landet

31.5.2024

 

Opdateret 31. maj kl. 16:30 UTC

• Vulkanudbruddet har holdt sig relativt stabilt de seneste 24 timer

• Lavastrømmen foregår hovedsageligt mellem Hagafell og Sýlingarfell

• Den gennemsnitlige lavastrøm i løbet af de første fire timer af udbruddet blev estimeret til omkring 1500 m³/s

• Vulkansk smog er blevet observeret i mange områder over hele landet. Luftkvaliteten kan overvåges her

• Gasforurening kan blive bemærket i Ölfus og hovedstadsområdet i de kommende dage

• Se den opdaterede farevurdering her

 

Vulkanudbruddet, der begyndte omkring middagstid den 29. maj, har været relativt stabilt i løbet af det seneste døgn. Aktiviteten på udbrudsspalten strækker sig fra placeringen af ​​det krater, der brød ud i den længste del af det forrige udbrud og nord for det. Lava strømmer fra krateret mod området mellem Hagafell og Sýlingarfell, og det bliver også tættere på krateret. Lava fra den nordlige del af sprækken strømmer mest mod øst. Der har ikke været fremskridt i lavastrømsfronterne vest for Grindavík.

Der har været begrænset seismisk aktivitet i området, og udbrudsskælven har holdt sig stabil siden i forgårs. Der blev målt betydelige nedsynkninger på GNSS-stationer i Svartsengi-området efter digets udbredelse i onsdags, men siden er der ikke registreret væsentlige ændringer, der indikerer fornyet magma-ophobning der. Målinger i de kommende dage vil give yderligere information om udviklingen af ​​magmaakkumulering under Svartsengi og udbruddets fremskridt.

Fotogrammetriholdet fra Islands Naturhistorisk Institut og Islands National Land Survey har behandlet data fra en luftundersøgelse foretaget omkring fire timer efter udbruddet begyndte, sammen med satellitbilleder. Baseret på disse data ses det, at arealet af lavafeltet var 8,7 km² og volumenet 24 millioner m³ kl. 17:06 den 29. maj. Den gennemsnitlige lavaudledning i løbet af de første fire timer af udbruddet er estimeret til ~1500 m³/s baseret på de samme data. Estimatet for lavaudledningen fra kraterne er ikke blevet opdateret siden da, men det kan antages, at det nu er meget lavere end ved begyndelsen af ​​udbruddet. Til sammenligning blev den gennemsnitlige lavaudledning i de første timer af udbruddet, der begyndte den 16. marts, estimeret til omkring 1100-1200 m³/s (mere information på webstedet for Institut for Jordvidenskab).

Vulkansmog er blevet opdaget

Vejrudsigten er sydvestlig vind frem til søndag, hvor vinden skifter til vestlig retning. Der vil komme lidt let nedbør i mange områder, især i den sydvestlige del af landet. Derfor vil gasforurening blive ført nordøst og senere mod øst, hvilket potentielt vil påvirke Ölfus og hovedstadsområdet i de kommende dage. Vulkansmog er blevet påvist i forskellige dele af landet i løbet af det seneste døgn og er blevet målt af Miljøstyrelsens overvågningsinstrumenter. Vulkansmog består af meget fine svovlpartikler (SO ₄ ), der dannes på grund af kemiske reaktioner mellem vulkanfanen og atmosfærisk fugt og ilt, hjulpet af sollys. Med lange dagslystimer, som det er tilfældet i øjeblikket, øges sandsynligheden for dannelse af vulkansk smog. Vulkansmog registreres ikke på SO ₂ gasmonitorer, men er synlig som en grå-blå dis, når den når en vis koncentration. En stigning i fine partikler (PM1 og PM2,5) kan indikere tilstedeværelsen af ​​SO ₄ . Luftkvaliteten kan overvåges på Miljøstyrelsens luftkvalitetshjemmeside.

I næste uge er der chancer for nordlige og nordvestlige vinde, hvilket betyder, at der er lille sandsynlighed for gas- og luftforurening i befolkede områder.

Dette satellitbillede (Sentinel-5p) taget kl. 13:47 i går, 30. maj, viser SO2-fanen båret østpå fra udbruddet, som blev opdaget i Østfjordene

Opdateret farevurdering

 

IMO har opdateret farevurderingen i lyset af udviklingen af ​​vulkanudbruddet. Zone 1, 5 og 7 er blevet nedgraderet fra høj fare til betydelig (orange). Den vigtigste ændring er, at chancerne for gasforurening, askefald og lavastrøm nu anses for at være lavere end før i disse områder. Der er fortsat en meget høj fare i zone 3 (lilla), som er Sundhnúkur-kraterrækken og udbrudskilden. Den samlede fare i zone 4 (Grindavík) forbliver uændret og anses stadig for høj (rød), selvom risikoen for udluftningsåbning, lavastrømning og askefald vurderes at være lavere end tidligere. Kortet forbliver gyldigt indtil 4. juni, medmindre forholdene ændres.

 

(Klik på kortet for at se det større)

 

Opdateret 30. maj kl. 14:00 UTC

• Væsentlig reduceret vulkansk aktivitet
• Lavastrømmen hovedsageligt i området omkring Hagafell
• Ingen eksplosiv aktivitet siden i går
• GPS-målinger tyder på, at jorden i Svartsengi-området aftog omkring 15 cm, da magma strømmede derfra
• Mulig gasforurening i S-Island i dag og i hovedstadsområdet i eftermiddag og i morgen
• Gasdistributionsprognose er tilgængelig her
• Betydelig usikkerhed om mængden af ​​gasser fra udbrudsstedet. Realtidsmålinger af luftkvalitet tilgængelige på webstedet for EnvironmentAgency of Iceland

 

Siden i går eftermiddags er aktiviteten på eruptivspalten ved Sundhnúkur-kraterrækken faldet markant. Aktiviteten i udbruddet har været den samme i nat og i morges, og den vulkanske rystelse har været stabil siden sidst i aftes. Der er ikke set eksplosiv aktivitet siden i går eftermiddags, hvor dampeksplosioner skete på grund af lava, der strømmede ind i sprækker og kom i kontakt med grundvandet ved Hagafell. Aktiviteten er størst tæt på krateret, der var aktivt i længst tid af udbruddet, der startede den 16. marts.

I går eftermiddags en måleflyvning over udbrudsstedet med personale fra fotogrammetri-teamet fra det islandske naturhistoriske institut og de nationale landmålinger af Island. Luftfotograferingsforholdene var udfordrende, da udbrudsfanen lå over en del af lavafeltet, der blev dannet ved udbruddets begyndelse. De data, der er indsamlet under luftundersøgelsen, behandles yderligere sammen med satellitbilleder for at få et klarere billede af lavaudledningens hastighed i de første par timer af udbruddet. Det medfølgende kort viser de groft estimerede konturer af lavafeltet, da det var omkring kl. 17 i går, eller da udbruddet havde varet i omkring fire timer. Placeringen af ​​eruptionsspalten er også angivet med røde stiplede linjer.

(Klik på kortet for at se det større)

GNSS-data viser 15 cm deflation i Svartsengi-området efter digets udbredelse

Satellitbilleder taget tidligt i morges den 30. maj viser ikke nævneværdige bevægelser på revner i Grindavík by. Deformationsmålinger i realtid indikerer også, at der ikke er målt nogen væsentlig deformation der siden i aftes.

GNSS-målinger viser 15 cm deflation i Svartsengi efter digets udbredelse derfra til Sundhnúksgígar-kraterrækken. Diget, der er dannet og nu nærer udbruddet, strækker sig fra bjerget Stóra-Skógfell til bjerget Hagafell. Det anslås, at omkring 15 millioner kubikmeter magma allerede har forladt magmaophobningen under Svartsengi.

Målinger og deformationsdata, der vil være tilgængelige i de kommende dage, vil give mere information om udviklingen af ​​magma-akkumulering under Svartsengi og den mulige udvikling af udbruddet. Meteorologisk Kontor fortsætter med at overvåge området og observere begivenhedens udvikling.

Gasspredningsprognose

Vejrudsigten for i dag (torsdag) forudser en vestlig vind, hvor gasforurening forventes at bevæge sig mod øst, hvilket potentielt vil blive bemærket i Ölfus og andre dele af det sydlige Island. En mere sydvestlig vind ventes senere på dagen og fortsætter i morgen (fredag). Det vil få gasforureningen til at bevæge sig mod nordøst og vil kunne opdages i hovedstadsområdet. Der er betydelig usikkerhed om mængden af ​​gasudledninger fra udbrudsstederne. Du kan følge gasspredningsprognosen og realtidsmålinger af forskellige gasser på hjemmesiden loftgaedi.is.

Meteorologisk kontor har modtaget meldinger om vulkansk dis i mange dele af landet, ligesom de er blevet målt på Miljøstyrelsens overvågningsinstrument i Húsavík i det nordlige Island. Ifølge gasspredningsprognosen kan en stor del af landet opleve vulkansk dis i dag. Vulkandis består af svovlpartikler (SO4) dannet på grund af kemiske reaktioner mellem udbrudsfanen og ilt i atmosfæren. Denne proces accelererer, når lufttemperaturen er højere, og solen skinner, som det var tilfældet i går, da udbruddet begyndte. Disse svovlpartikler detekteres ikke af SO2-gasmålere, men er synlige som en gråblå dis, når en vis koncentration er nået. En stigning i fine partikler (PM1 og PM2.5) kan indikere tilstedeværelsen af ​​SO4. Værdierne målt i dag ligger ikke over nogen sundhedstærskel, men du kan overvåge Miljøstyrelsens luftkvalitetsmålere .

 

Opdateret 29. maj kl. 19:10 UTC

• Hoveddelen af ​​eruptivspalten er omkring 2,4 km lang

• Lavaen er strømmet over Grindavík-vejen og Nesvegur-vejen

• Ekstruderingshastigheden ved begyndelsen af ​​udbruddet blev estimeret til 1.500-2.000 m ³ /s

• I nat skifter vindretningen mod sydvest. Gasforurening kan forekomme i hovedstadsområdet i aften og i morgen (30. maj)

 

Der er stadig et betydeligt lavaspringvand på hoveddelen af ​​sprækken, som er omkring 2,4 km lang. Den eruptive sprække strækker sig syd for Hagafell og lava strømmer kraftigt derfra, mest mod syd og vest. Lava er strømmet over Grindavík-vejen mod Þorbjörn og videre langs lavabarriererne vest for Grindavík, der oversvømmer en del af Nesvegur-vejen. En del af lavaen, der flyder mod syd, løber ind i en sprække ved Hagafell, hvor den flyder under jorden, før den kommer frem lige nord for lavabarriererne nordøst for Grindavík. En lavalap nord for Sýlingafell flyder mod vest, og den nærmer sig Grindavík-vejen ved Svartsengi.

Modelberegninger tyder på, at der fra kl. 16:30 UTC er strømmet omkring 14 millioner m ³ /s magma fra magmareservoiret under Svartsengi til Sundhnúkur-kraterrækken. Deformationshastigheden er faldet betydeligt, men magma fortsætter med at strømme fra magma-reservoiret under Svartsengi til Sundhnúkur-kraterrækken.

 

Kort før klokken 16:00 UTC begyndte eksplosiv aktivitet, da magmaen kom i kontakt med grundvandet, hvor en lava strømmer ind i en sprække ved Hagafell. Magmaet får vandet til hurtigt at blive omdannet til gasformig tilstand (damp), hvilket forårsager dampeksplosioner og tephrafald (aske).

Der er betydelig usikkerhed omkring mængden af ​​gasser fra udbrudsstedet. I nat skifter vindretningen mod sydvest og derfor føres gasforurening mod nordøst og kunne mærkes i hovedstadsområdet i nat og i morgen (torsdag). Gasfordelingsprognose kan ses her og realtidsmålinger af forskellige gasser på loftgaedi.is

 

(Klik på kortet for at gøre det større)

 

Opdateret 29. maj kl. 14:50 UTC

• Et vulkanudbrud startede ved Sundhnúkur-kraterrækken kl. 12:46 UTC i dag

• Lavaen flyder over Grindavík vej

• Eruptivspalten er nu omkring 3,4 km lang

• Ekstruderingshastigheden er groft estimeret til 1.500-2.000 m ³ /s

• Seismisk aktivitet er faldet hurtigt

 

Det ser ud til, at det meste af kraften i udbruddet nu er i den sydlige ende af sprækken, der åbnede tidligere i dag. Ifølge oplysninger fra kystvagtens overvågningsflyvning er der en ret intens lavastrøm omkring Hagafell mod øst og derefter sydpå mod Melhólsnáma.

Den sydligste åbning af sprækken er nu mindre end en kilometer væk fra lavabarriererne nord for Grindavík.

Det første skøn fra videnskabsmænd er, at starten på dette udbrud er kraftigere end ved tidligere udbrud i området, men ekstruderingshastigheden er groft estimeret til 1.500-2.000 m ³ /s.

Opdateret 29. maj kl. 14:15 UTC

Lavaen er strømmet omkring 1 km mod vest, og der er en betydelig strøm syd for Stóra-Skógfell mod Grindavík-vejen. Klokken lidt over 14 nåede vulkanfanen omkring 3,4 km til luften. En anden vulkansk sprække åbnede sig vest for det største krater, der blev dannet i udbruddet, der startede den 16. marts 2024. Ekstruderingshastigheden er groft estimeret til at være 1.000 m ³ /s.

Gasforurening vil være mod sydøst og senere i dag mod øst og kan derfor mærkes i Selvogur og Ölfus. Vindretningen skifter i nat mod sydvest og dermed føres gasforurening mod nordøst og vil kunne mærkes i hovedstadsområdet i nat og i morgen (torsdag).

 

Opdateret 29. maj kl. 11:40 UTC

 

Intens seismisk aktivitet er i gang på Sundhnúkur-kraterrækken. En magma- udbredelse kan være i gang eller er startet, og et vulkanudbrud kan følge.  

 

Opdateret 24. maj kl. 16:00 UTC

• Stærk vind ind i natten kan påvirke følsomheden af ​​seismiske sensorer.

• Deformationsdata viser, at landhævningen ved Svartsengi fortsætter

• Omkring 18 millioner kubikmeter magma er blevet tilført magmareservoiret siden 16. marts.

• Stadig øget sandsynlighed for endnu en digeudbredelse og et udbrud

• Sundhnúkur-kraterrækken er stadig det mest sandsynlige sted for et vulkanudbrud

• Tiden for udbrudsforstadiet kan være meget kort

 

Omkring 140 jordskælv er detekteret i urolighedsområdet de seneste to dage, alle målte under M2,0. De fleste af jordskælvene er lokaliseret enten i området mellem bjerget Stóra-Skógfell og bjerget Hagafell eller syd for bjerget Þorbjörn. I dag er der fundet færre jordskælv i området sammenlignet med tidligere dage. Det skyldes kraftige vinde, der påvirker de seismiske sensorers følsomhed til at måle de allermindste jordskælv. Vejret forventes fortsat at påvirke de seismiske sensorers følsomhed ind i natten, men det påvirker ikke andre sensorer, der bruges til at overvåge området.

Deformationsdata viser en stabil og fortsat stigning i Svartsengi-regionen, hvilket indikerer, at magma fortsætter med at akkumulere der i dybden. Modelberegninger anslår, at ~18 millioner kubikmeter har samlet sig der siden den 16. marts, ^hvor det sidste udbrud begyndte. Det samlede volumen af ​​akkumuleret magma er mere nu end i de seneste tidligere begivenheder. Det betyder, at trykket i systemet fortsætter med at stige, og derfor kan det konkluderes, at der stadig er betydelige odds for en ny digeudbredelse efterfulgt af et udbrud. Tidspunktet for, hvornår dette vil ske, er dog ret usikkert, men forløberen kan være meget kort.

Grafen viser den estimerede mængde magma, der er akkumuleret under Svartsengi mellem vulkanudbrud eller magma-indtrængninger, der har fundet sted siden november 2023. De små ændringer, der er synlige på grafen, er inden for fejlmarginen og er blevet observeret før under magma-akkumuleringsprocessen , hvilket indikerer, at magmaproduktionen er forblevet stabil, og at der ikke er sket væsentlige ændringer i magmastrømmen under Svartsengi siden november 2023.

 

Opdateret 21. maj kl. 17:30 UTC

• Magmaakkumulering under Svartsengi fortsætter med en stabil hastighed

• Omkring 17 millioner m3 er blevet genopladet i magma-akkumuleringszonen siden begyndelsen af ​​det sidste udbrud (16. marts)

• Stadig øget sandsynlighed for endnu en digeudbredelse og et udbrud

• Den forudgående tid før et udbrud kan være kort

 

Omkring 200 jordskælv blev registreret i urolighedsområdet i løbet af sidste weekend, de fleste af dem under M1,0. Det er ligesom seismiciteten i sidste uge, hvor der blev målt omkring 40 til 80 jordskælv hver dag. De fleste af jordskælvene er lokaliseret enten i området mellem Stóra-Skógfell og Hagafell eller syd for Þorbjörn.

Magma-akkumulering fortsætter under Svartsengi-regionen, og løftningen fortsætter også med en jævn hastighed der. Mindre ændringer i hastigheden kan ses mellem dage på de følgende grafer, men generelt fortsætter tendensen med en konstant hastighed. På dette tidspunkt antages det stadig, at der er øget sandsynlighed for en digeudbredelse og/eller et udbrud ved Sundhnúksgígar-kraterrækken.

Sidste nyhedsopdatering rapporterede øget mikroseismicitet i løbet af de sidste uger i området syd for Mt. Þorbjörn og vest for Grindavík. Det blev også nævnt, at det ville være muligt, at magma kunne finde vej gennem svagheder i skorpen der. På dette tidspunkt anses dette scenarie for meget usandsynligt. Den fortolkning er baseret på ny geodætisk modellering og andre data diskuteret på et videnskabeligt møde i går, 21. maj.

Denne gradvise stigning i seismicitet er sandsynligvis et tegn på spændingsfrigivelse i og omkring digets indtrængning ved Sundhnúksgígar-kraterrækken på grund af øget tryk i magma-akkumuleringszonen under Svartsengi.

Det mest sandsynlige scenario anses stadig for at være en digeudbredelse og/eller et udbrud ved Sundhnúksgígar-kraterrækken.

HS Orka overvåger trykændringer i boringer i Svartsengi-regionen. Pludselige trykændringer har været et af de foreløbige signaler, der er set før sidste digeudbredelse og udbrud. Det er tidligere blevet rapporteret, at tegnene på en ny digeudbredelse ville være lokaliseret seismisk sværm, ændringer i deformationshastigheden og trykændringer i boringer. Mindre tryksvingninger blev observeret i går i et borehul i Svartsengi-regionen, men der var ingen signifikant stigning i seismicitet eller deformation på samme tid. Derfor blev det ikke vurderet, at tryksvingningerne var tegn på en digeudbredelse.

 

Opdateret 17. maj kl. 17:00 UTC

• Magmaakkumulering under Svartsengi forbliver stabil.

• Omkring 16 millioner kubikmeter magma er blevet tilført magmareservoiret siden 16. marts.

• Fortsat øget sandsynlighed for endnu en digeudbredelse og endnu et vulkanudbrud.

• Sundhnúkur-kraterrækken er stadig det mest sandsynlige sted for et vulkanudbrud.

• Varsel om et udbrud kan være meget kort.

• Nødvendig at være forberedt på andre scenarier end et vulkanudbrud på Sundhnúkur-kraterrækken.

 

Omkring 50 jordskælv blev registreret i området omkring diget i går den 16. maj, de fleste under M1,0. Dette svarer til den seismiske aktivitet, der er blevet opdaget i de seneste dage, men omkring 50 til 80 jordskælv er blevet målt om dagen, de fleste af dem forekommer i to hovedområder, mellem Stóra-Skógfell og Hagafell og syd for Þorbjörn.

Magma-akkumulering fortsætter under Svartsengi, og landhævningen fortsætter i samme hastighed som før. Derfor er der stadig en øget sandsynlighed for, at der i de kommende dage kan ske et nyt digeindbrud og endnu et vulkanudbrud i Sundhnúkur-kraterrækken.

Det sidste udbrud i Sundhnúkur-kraterrækken startede den 16. marts. I de 62 dage, der er gået siden da, er omkring 16 millioner kubikmeter magma blevet tilført magma-reservoiret under Svartsengi. Dette er den længste periode med magma-akkumulering siden dette scenarie begyndte i slutningen af ​​oktober 2023.

 

Opdateret farevurdering og mulige scenarier.

 

Det islandske meteorologiske kontor har offentliggjort et opdateret farevurderingskort, der er gyldigt indtil den 21. maj med forbehold for enhver udvikling. Faren for gasforurening i forbindelse med en øget sandsynlighed for endnu et vulkanudbrud anses nu for at være høj i område 7, men var tidligere betydelig. På grund af ændringen er den samlede fare i området nu vurderet som betydelig (organge), men var tidligere moderat (gul). Fare på grund af gasforurening i andre områder er uændret i forhold til sidste uge og vurderes som betydelig. På grund af øget mikroseismicitet i område 4 er risikoen for jordskælv blevet øget.

IMO har også opdateret de scenarier, der anses for mest sandsynlige.

Scenarie 1 Vulkanudbrud mellem Sýlingarfell og Stóra-Skógfell (Central del af zone 3 på farevurderingskort). Lignende sted som hvor udbruddene startede den 18. december 2023, den 8. februar og den 16. marts 2024.

 

• Sandsynlige forstadier er lokaliserede, lille seismisk sværm mellem Stóra-Skógfell og Sýlingarfell, acceleration af deformation og trykændringer i boringer i området.

• Meget kort varsel (mindre end 30 minutter), selv ingen varsel på grund af skorpen, der allerede er brækket.

• Lava kunne nå Grindavíkurvegur på 2 til 4 timer.

 

 

Scenarie 2 – Vulkanudbrud syd eller sydvest for Hagafell (den sydligste del af zone 3 på farevurderingskortet). Lignende sted som hvor udbruddet startede den 14. januar 2024.

 

•  Sandsynlige forstadier er en lille seismisk sværm, der starter nær Stóra-Skógfell eller Sýlingarfell og bevæger sig mod syd, acceleration af deformation og trykændringer i boringer i området.

• Varslet om et udbrud i denne zone vil sandsynligvis være længere end i scenario 1, men det er usikkert hvor meget længere.

• Lava kunne nå barriererne ved Grindavík på omkring 1 time.

• Et digeindbrud, der strækker sig syd for Hagafell, vil sandsynligvis forårsage betydelige sprækkebevægelser i Grindavík.

 

 

Den samlede mængde magma i magma-reservoiret under Svartsengi har aldrig været større end før 10. november 2023. Andre scenarier skal overvejes, hvis magma-akkumulering fortsætter uden magma-udbredelse eller vulkanudbrud.

Hidtil har man overvejet mængden af ​​magma, der er blevet tilføjet til magmareservoiret mellem magmaudbredelse eller -udbrud. I forbindelse med stigende magmatryk i magmareservoiret under Svartsengi, er det nødvendigt at overveje den samlede mængde magma, der skønnes at være til stede. 

Mellem 25. oktober og 10. november 2023 akkumulerede mere end 10 millioner m ³ magma under Svartsengi. Det anslås, at omkring 80 millioner m ³ magma forplantede sig fra magmareservoiret under dannelsen af ​​et 15 km langt digeindbrud den 10. november. Det kan derfor antages, at omkring 70 millioner m ³ magma var til stede i magmareservoiret under Svartsengi på det tidspunkt. Magma-akkumulering er fortsat uafbrudt siden da, og magma er strømmet ud mindst fem gange fra Svartsengi til Sundhnúksgígar-kraterrækken. Fire af disse fem gange har resulteret i et udbrud.

Hver magmaudbredelse eller vulkanudbrud har ikke udtømt magmaakkumuleringsområdet, og derfor har den indledende status for magmaakkumulering under Svartsengi varieret i hver cyklus efter november 2023, som vist i figuren nedenfor.

Billedtekst: Graf, der viser udviklingen af ​​magma-akkumulering og den estimerede samlede mængde af magma i magma-reservoiret under Svartsengi siden 25. oktober. Hver magma-udbredelse udtømte ikke reservoiret, og derfor vil startstatus for akkumulering under Svartsengi variere i hver cyklus efter november 2023. Grafen viser, at den samlede mængde magma aldrig har været højere siden dannelsen af ​​det 15 km lange dige den 10. november.

Der er nogle ligheder mellem denne sekvens af begivenheder i Sundhnúkur-kraterrækken og den, der fandt sted i Krafla-brandene, der startede i 1975. Over en 10-årig periode var der 20 magmaudbredelser, hvoraf 9 endte i et udbrud. Under Kraflabrandene brød udbredelsen alle ind i den samme digeindtrængning, men varierede i størrelse. Erfaringer fra Krafla-brandene tyder på, at efterhånden som antallet af magma-udbredelser stiger, er der behov for mere tryk for at udløse dem. Derfor må det anses for sandsynligt, at magma igen vil strømme fra magma-reservoiret under Svartsengi ind i Sundhnúkur-kraterrækken.

Billedtekst: Figurer, der viser sammenhængen mellem dannelsen af ​​et digeindbrud og landhøjden midt i Krafla-calderaen. Den nederste figur viser højden af ​​målepunktet inden for calderaen, mens den øverste figur viser afstanden (km) af begivenheder fra Krafla-calderaen i hver begivenhed, med rød farve, der repræsenterer et vulkanudbrud (Páll Einarsson og Bryndís Brandsdóttir, 2021) .

Den samlede mængde magma i reservoiret under Svartsengi har aldrig været højere, siden den 15 km lange digeinstrusion dannedes den 10. november. Efterhånden som der går mere tid uden en ny magma-udbredelse ind i Sundhnúkur-kraterrækken, øges sandsynligheden for, at magma finder vej til andre områder, hvor der er svaghed i jordskorpen.

Mikroseismisk aktivitet har været i gang i de sidste par uger i området syd for Þorbjörn, i den store sprækkedal ved Grindavík. I dette område er der svagheder i jordskorpen og dermed kan magma nå overfladen der. Det faktum, at magma strømmer fra magmareservoiret til området syd for Þorbjörn, er på dette tidspunkt et mindre sandsynligt scenarie end de ovenfor nævnte. Derfor er dette scenarie ikke taget i betragtning i den opdaterede farevurdering. Det islandske meteorologiske kontor vil indsamle og behandle data i løbet af de næste par dage for at kaste et bedre lys over denne mulighed.

Kortet viser jordskælv fra 10.-16. maj. Den øverste graf viser størrelsen af ​​jordskælvene, og den nederste graf viser antallet af jordskælv hver dag i samme periode.

 

Opdateret 16. maj kl. 13:00 UTC

• Magma-akkumulering under Svarstengi fortsætter med en jævn hastighed.

• Omkring 16 millioner kubikmeter magma er blevet tilført magmareservoiret.

• Øget sandsynlighed for endnu en digeudbredelse og/eller et vulkanudbrud i de kommende dage.

• Sundhnúkur-kraterrækken er det mest sandsynlige sted for et andet udbrud.

• Et udbrud kan starte med meget kort (eller ingen) advarselstid

 

Omkring 80 jordskælv blev registreret i området omkring diget i går den 15. maj, de fleste under M1,0. Dette svarer til den seismiske aktivitet, der er blevet opdaget i de seneste dage, men omkring 50 til 80 jordskælv er blevet målt om dagen, de fleste af dem forekommer i to hovedområder, mellem Stóra-Skógfell og Hagafell og syd for Þorbjörn. Tegn på ny magmavandring fra Svartsengi reservoiret til det tidligere digeområde kan omfatte lokale små seismiske sværme i og omkring intrusionen, hurtige ændringer i deformation og trykændringer i boringer i området.

Magmaophobning fortsætter under Svartsengi, og landhævningen foregår i samme hastighed som den, der er observeret siden begyndelsen af ​​april 2024. Derfor er der stadig en øget sandsynlighed for, at der i de kommende dage kan forekomme et nyt digeindbrud og endnu et vulkanudbrud i Sundhnúkur-kraterrækken .

Forud for tidligere digeindbrud og vulkanudbrud var omkring 8 til 13 millioner kubikmeter blevet tilføjet til magmareservoiret, før reservoiret svigtede, og magma strømmede fra dette til Sundhnúkur-kraterrækken. Nu er mængden af ​​tilført magma mere end den øvre grænse, da der i alt er blevet tilføjet ~16 millioner kubikmeter til reservoiret siden 16. marts, hvor det sidste udbrud startede.

Lektionen fra Krafla-brandene var, at efterhånden som antallet af digeudbredelser stiger, er der behov for mere pres for at udløse dem. Derfor må det anses for sandsynligt, at der igen vil strømme magma fra Svartsengi-magma-reservoiret til Sundhnúkur-kraterrækken, men der er usikkerhed om, hvornår der opnås tilstrækkeligt tryk til at udløse en ny digeudbredelse og/eller -udbrud.

 

 

Grafen viser den estimerede mængde magma, der er blevet genopladet til Svartsengi magma reservoir mellem de udbrud eller digeudbredelser, der har fundet sted siden november 2023. I tidligere digningsbegivenheder og udbrud er omkring 8 til 13 millioner kubikmeter blevet tilføjet magmaen reservoir, før reservoiret svigtede, og magma flød ind i Sundhnúkur-kraterrækken. Nu har magmamængden overskredet den øvre grænse, da der er tilføjet ~16 millioner kubikmeter til reservoiret siden 16. marts, hvor det sidste udbrud begyndte.

 

Opdateret 13. maj kl. 15:00 UTC

• Der er øget sandsynlighed for et nyt digeindbrud og endnu et udbrud i de kommende dage.

• Det mest sandsynlige sted for et nyt udbrud er Sundhnúk-kraterrækken.

• Advarselsskilte forud for et udbrud kan være meget korte.

 

Jordhævningen fortsætter i Svartsengi-området i samme hastighed som tidligere observeret. Siden den 16. marts, hvor det sidste vulkanudbrud begyndte, har jordløftet nået cirka 20 cm ved GNSS-stationen i Svartsengi. Magmaophobningen fortsætter i reservoiret, og sandsynligheden for et nyt digeindbrud og et nyt udbrud stiger fortsat.

I de tidligere digeindtrængninger og udbrud i løbet af de sidste mange måneder blev cirka 8 til 13 millioner kubikmeter magma genopladet til reservoiret under Svartsengi mellem begivenhederne, før magmaen migrerede til overfladen mod Sundhnúk-kraterrækken. Nu har mængden af ​​magma tilføjet siden 16. marts overskredet den tidligere observerede øvre grænse.

Seismisk aktivitet er relativt stabil mellem dage. I den sidste uge blev der registreret omkring 50 til 80 jordskælv om dagen, hovedsagelig i områderne mellem Stóra-Skógfell og Hagafell og syd for Þorbjörn. De fleste af jordskælvene har størrelsesordenen under 1,0, men der er registreret isolerede jordskælv med størrelsesordenen tæt på 2,0. Tegn på et nyt digeindtrængen forventes at svare til de tidligere observerede, såsom lokaliseret seismisk aktivitet i og omkring diget, hurtig jorddeformation og trykændringer i nærliggende boringer.

Det islandske meteorologiske kontor fortsætter sin 24-timers overvågning af området. Nye eruptive sprækker kan åbne sig i området mellem Stóra-Skógfell og Hagafell, og tegn på magma, der migrerer mod overfladen, vil sandsynligvis ligne de indledende faser af andre nylige udbrud i området. Dette kan ske med lidt eller ingen advarsel.

Grafen viser det estimerede volumen af ​​magma, der er genopladet under Svartsengi-området mellem rækken af ​​vulkanudbrud og digeindtrængninger, der begyndte i november 2023. Bemærk, at en geomagnetisk storm i weekenden forstyrrede målingerne. (Se diskussionen nedenfor.)

Forstyrrelse i GNSS-målinger på grund af den geomagnetiske storm

Landhævning beregnes ved at måle ændringen i den tid, det tager for et signal at rejse fra satellitter, der kredser om jorden, til GNSS-modtagere på jorden. Hvis varigheden af ​​tid for signalet til at rejse mellem satellitten og modtageren aftager, indikerer det, at landet har hævet sig.

I weekenden opstod en af ​​de kraftigste geomagnetiske storme i de senere år, da solvinde fra store solpletter på Solen ramte Jorden. Den sidste geomagnetiske storm af samme størrelsesorden fandt sted den 30. oktober 2003.

Stærke solvinde sender ladede partikler ind i Jordens magnetfelt, hvilket påvirker signaltransmissioner mellem GNSS-modtagere på jorden og satellitter. Denne interferens påvirker signalets rejsetid, hvilket forårsager deformationsmålinger, der kunne fortolkes som en afmatning i magmaakkumuleringshastigheden. Dette er dog ikke tilfældet, da et nyt datapunkt beregnet her til morgen ligger på et “normalt” sted i forhold til tidligere målinger. (Se grafen ovenfor).

Forstyrrelser på grund af geomagnetiske storme påvirker ikke det islandske meteorologiske kontors mulighed for at give advarsler om forestående digeindbrud eller udbrud.

 

Opdateret 10. maj kl. 18:00 UTC

• Der er øget sandsynlighed for et nyt digeindbrud og endnu et udbrud i de kommende dage.

• Det mest sandsynlige sted for et nyt udbrud er Sundhnúk-kraterrækken.

• Advarselsskilte forud for et udbrud kan være meget korte.

• Der er udstedt et opdateret farevurderingskort.

 

Tendensen med landstigning ved Svartsengi har forblevet relativt stabil, siden det seneste vulkanudbrud sluttede, med magma-akkumulering fortsatte med en lignende hastighed. Fra i dag anslås det, at der er tilføjet cirka 14 millioner kubikmeter magma til magmakammeret siden udbruddet begyndte den 16. marts.

I digets indtrængninger og udbrud i løbet af de sidste par måneder blev der tilføjet cirka 8 til 13 millioner kubikmeter magma til kammeret under Svartsengi, før det forlod kammeret og rejste mod Sundhnúk-kraterrækken. Nu har mængden af ​​tilført magma overskredet den tidligere observerede øvre grænse. Observationer fra Krafla-udbruddene kan tilføje kontekst til denne adfærd og afsløre, at efterhånden som flere digeindtrængninger forekommer, kræves der mere pres for at igangsætte dem. Derfor er det sandsynligt, at magmakammeret under Svartsengi i sidste ende vil føde endnu en indtrængen i Sundhnúk-kraterrækken. Der er dog usikkerhed om, hvornår der opnås tilstrækkeligt tryk til at igangsætte et nyt digeindtrængning og potentielt et udbrud, hvis magma når overfladen.

Graf, der viser den estimerede mængde magma, der har ophobet sig under Svartsengi mellem de udbrud og digeindtrængninger, der har fundet sted på Reykjanes siden november 2023.

Det islandske meteorologiske kontor fortsætter sin 24-timers overvågning af området for nøje at overvåge aktiviteten. Nye eruptive sprækker kan åbne sig i området mellem Stóra-Skógfell og Hagafell og kan ligne de indledende faser af andre nylige udbrud i området. Dette kunne ske med lidt eller ingen advarsel. Tegn på en ny digeindtrængen vil ligne dem, der tidligere er observeret: Lokaliserede jordskælv i og omkring diget, accelereret deformation og trykændringer i nærliggende boringer.

Øget seismisk aktivitet er blevet registreret ved Sundhnúk-kraterrækken i de seneste dage. Denne stigning i seismisk aktivitet er sandsynligvis et tegn på, at stress frigives i og omkring det nylige udbrudssted på Sundhnúk-kraterrækken på grund af øget tryk i magmakammeret under Svartsengi.

I aftes opdagede det islandske meteorologiske kontors 24-timers overvågningshold en stigning i lokaliseret seismisk aktivitet syd for Stóra-Skógfell, på et lignende sted som hvor tidligere udbrud er startet. Deformations- og trykmålinger, som skulle indikere et digeindbrud, viste ikke væsentlige ændringer. Aktiviteten varede i relativt kort varighed, men det kan ikke udelukkes, at der kan være injiceret en lille mængde magma der.

Farligt at færdes i nærheden af ​​Sundhnúk-kraterrækken

Det islandske meteorologiske kontor har udsendt en opdateret farevurdering. Afslutningen af ​​det sidste udbrud har medført opdateringer i flere områder, men den nuværende farevurdering afspejler øgede chancer for et nyt digeindbrud og muligt udbrud.

Da skorpen mellem Stóra-Skógfell og Hagafell er kraftigt sprækket, vil magma sandsynligvis finde en klar vej til overfladen uden væsentlig modstand, og derfor vil betydelig seismisk aktivitet muligvis ikke ledsage magmavandring gennem skorpen. Derfor kan varslingstider før et nyt udbrud være meget korte eller ikke-eksisterende, så det er vigtigt at udvise ekstrem forsigtighed, når man rejser til område 3, defineret på det islandske meteorologiske kontors farekort. Den nye risikovurdering er gældende indtil 14. maj, medmindre situationen ændrer sig.

 

Opdateret 7. maj kl. 17:45 UTC

• Landstigningen fortsætter i Svartsengi

• Hastigheden af ​​magmaakkumulering forbliver den samme som den, der er observeret i de seneste uger

• Den synlige aktivitet i det aktive krater er faldet de seneste dage

• Der er en stigende sandsynlighed for, at det aktuelle udbrud kan stige i intensitet, eller at en ny eruptiv sprække kan åbne

• Advarsel om øget vulkansk aktivitet eller et nyt udbrud kan være meget kortvarigt

• Gasspredningsprognosen kan følges her

• Farevurderingen forbliver uændret

 

Udbruddet ved Sundhnúk-kraterrækken fortsætter. Lava fortsætter med at strømme et kort stykke fra den aktive udluftning, men aktiviteten i dette krater er aftagende. I løbet af den seneste uge er der kun blevet observeret ringe eller ingen ændringer i den sydlige del af lavafeltet nær de defensive barrierer øst for Grindavík.

Magmaophobning og landstigning fortsætter i Svartsengi. Kursen har været konstant i de seneste uger (se figuren nedenfor). Disse målinger indikerer, at trykket fortsætter med at stige i magmakammeret. Derfor er en ny digeindtrængning fra magmakammeret under Svartsengi mod Sundhnúk-kraterrækken fortsat mulig.

Seismisk aktivitet er steget støt i og omkring udbrudsområdet den seneste uge. De fleste af jordskælvene, som generelt er mindre end størrelsesordenen 1, er placeret nord for det nuværende udbrudssted, mellem Sundhnúk og Stóra Skógfell, syd for Þorbjarnar i den store dal nær Grindavík, og mellem Grindavík og det nuværende udbrudssted. Denne gradvise stigning i seismisk aktivitet er sandsynligvis et tegn på, at der frigives stress omkring udbrudsstedet på Sundhnúk-kraterrækken på grund af øget tryk i magmakammeret under Svartsengi.

Denne figur viser et kort med placeringen af ​​jordskælv siden den 15. april ⁽ venstre), sammen med automatiske størrelser (øverst til højre) og antallet af jordskælv pr. dag (nederst til højre).

Dette er de mest sandsynlige to scenarier vedrørende fortsættelsen af ​​aktiviteten ved Sundhnúkur-kraterrækken:

 

• Nye eruptive sprækker kan åbne sig i området mellem Stóra-Skógafell og Hagafell, og/eller det nuværende udbrudssted kan udvides på grund af en pludselig stigning i lavastrømmen, som kan sammenlignes med de indledende faser af det sidste vulkanudbrud i området. Dette kan ske med meget lidt eller ingen advarsel.
• Det er også muligt, at strømmen af ​​magma fra magmakammeret under Svartsengi ind i den aktive udluftning ved Sundhnúkur-kraterrækken kan stige støt, indtil der er ligevægt mellem indstrømningen af ​​magma ind i kammeret og udstrømningen til overfladen.

 

Tegn på et nyt vulkanudbrud vil sandsynligvis omfatte en pludselig stigning i jordskælv i og omkring udbrudsområdet, en acceleration i deformation og trykændringer i nærliggende boringer. Det er vigtigt at forstå, at advarselstider kan være ikke-eksisterende eller meget korte, muligvis mindre end en halv time.

Farevurderingen er uændret siden sidste opdatering. I den seneste uge er risikoen for mulige aktive lavastrømme i område 4 (Grindavík) steget fra betydelig til høj, baseret på de scenarier, der nu anses for mest sandsynlige.

(Klik på kortet for at se en større version)

Det er svært at forudsige, hvornår der kan være en ende på den igangværende sekvens af uroligheder, der begyndte i slutningen af ​​oktober

Som tidligere nævnt er der stadig usikkerhed om forløbet af denne episode, nu hvor vulkanudbruddet har været i gang i over en måned, mens magma fortsætter med at ophobes i magmakammeret under Svartsengi. Selvom scenarierne skitseret ovenfor anses for at være mest sandsynlige, er tæt overvågning i gang for at afgøre, om magma søger andre veje end mod Sundhnúk-kraterrækken. Områder nord for Stóra-Skógfell og syd for Hagafell og Þorbjarnar overvåges nøje.

Hvis magma bevæger sig mod overfladen uden for de områder, hvor de seneste udbrud allerede har fundet sted, forventes advarselssignalerne at være mere signifikante og manifestere sig med stærkere og mere intens seismicitet end observeret i optakten til de seneste udbrud.

 

 

Opdateret 2. maj kl. 18:00 UTC

• Landstigningen fortsætter ved Svartsengi. Tryk fortsætter med at bygge op i magmakammeret.

• Lavastrømmen fra krateret, som har været aftagende de seneste dage, fortsætter.

• Målinger og simuleringer indikerer, at der er betydelig usikkerhed om fremtiden. Sandsynligheden for et nyt vulkanudbrud og/eller en stigning i intensiteten af ​​udbruddet ved Sundhnúkur-kraterrækken vokser.

• Der er risiko for, at lava kan bryde Grindavíks østlige forsvarsværk, hvis udbruddets styrke igen øges.

• Farevurderingen forbliver uændret.

 

Landdeformation bliver fortsat målt ved Svartsengi, og hævningshastigheden har været stabil i de seneste uger (se billedet nedenfor). Tidligere på ugen var der indikationer på, at stigningstakten for landstigninger kunne være aftaget i de foregående dage. Målinger siden afslører dog, at kursen har været stabil i de seneste par uger. Trykket fortsætter med at stige inde i magmakammeret, og der er risiko for, at magmakammeret under Svartsengi vil føde et nyt vulkanudbrud.

Grafen viser jordens bevægelse i den lodrette komponent ved GPS-stationen SKSH i Svartsengi. Målingerne indikerer, at hastigheden af ​​jorddeformation har været stabil siden begyndelsen af ​​april. Den blå linje repræsenterer tidspunktet for magma-indtrængningen, som ikke kulminerede i et udbrud, mens de røde linjer repræsenterer digebegivenheder, der resulterede i et udbrud. Den anden røde linje viser begyndelsen af ​​det igangværende vulkanudbrud.

Seismisk aktivitet er steget langs Sundhnúkur-kraterrækken i de seneste dage. Disse jordskælv er små, hvilket sandsynligvis repræsenterer en frigivelse af stress i og omkring det stadigt mere tryksatte magmakammer under Svartsengi.

Lavastrømmen fra det aktive krater er væsentligt lavere end for tre uger siden, og den nuværende strømningshastighed er målt til at være relativt lille. En eventuel stigning i strømningshastigheden skal dog overvejes på trods af den i øjeblikket minimale lavastrøm.

Det medfølgende kort viser ændringer i lavastrømmens tykkelse mellem 15. april, 25. april og 30. april.

Lava fra krateret har samlet sig nær Grindavíks østlige forsvarsmur i de seneste uger (L12 på billedet ovenfor). Hvis intensiteten af ​​udbruddet stiger eller nye sprækker åbner sig syd for det nuværende udbrudssted, forventes det, at lavastrømmen vil rykke frem mod det østlige forsvar af Grindavík. Lørdag den 27. april krydsede små lavastrømme forsvaret øst for Grindavík. Hvis udbruddets kraft øges igen, er der risiko for, at sådanne hændelser bliver hyppigere.

Dette er de mest sandsynlige to scenarier vedrørende fortsættelsen af ​​aktiviteten ved Sundhnúkur-kraterrækken:

• Nye vulkanske sprækker kan åbne sig i området mellem Stóra-Skógafell og Hagafell, og/eller det nuværende udbrudssted kan udvides på grund af en pludselig stigning i lavastrømmen, som kan sammenlignes med de indledende faser af det sidste vulkanudbrud i området. Dette kan ske med meget lidt eller ingen advarsel.

• Det er også muligt, at strømmen af ​​magma fra magmakammeret under Svartsengi ind i den aktive udluftning ved Sundhnúkur-kraterrækken kan stige støt, indtil der er ligevægt mellem indstrømningen af ​​magma ind i kammeret og udstrømningen til overfladen.

Foreløbige signaler om et nyt vulkanudbrud ville ligne tidligere begivenheder med pludselig og intens seismisk aktivitet i og omkring magmakammeret og landdeformation i Svartsengi.

Det islandske meteorologiske kontors farevurdering forbliver uændret og er gyldig indtil den 7. maj, medmindre situationen ændrer sig.

Følg meteorologens prognose for gasudslip her .

 

Opdateret 26. april kl. 17:30 UTC

• En del af lavafeltet nær barriererne øst for Grindavík fortsætter langsomt med at blive tykkere.

• Jordhævningen i Svartsengi-området fortsætter med konstant hastighed.

• Så længe magmaen fortsætter med at akkumulere i Svartsengi-reservoiret, øges sandsynligheden for en betydelig eskalering af den eruptive aktivitet i Sundhnúk-kraterrækken.

• Fortsat fare på grund af gasemissioner i området.

 

Udbruddet ved Sundhnúkur fortsætter med et krater lige øst for Sundhnúkur, der forbliver aktivt fra den 5. april. Lavastrømme rejser et kort stykke syd for krateret i en åben lavakanal, men fortsætter videre i lukkede kanaler. En del af lavafeltet nær barrieren øst for Grindavík fortsætter langsomt med at tykne.

Billede fra det islandske meteorologiske kontors web-kamera taget klokken 4:30 i morges, kort før solopgang. Kameraet er placeret på toppen af ​​Þorbjörn og ser nordøst mod krateret.

Jordhævningen i Svartsengi-området fortsætter med konstant hastighed. Analytiske modeller tyder på, at mængden af ​​magma, der genoplades i reservoiret under Svartsengi, siden udbruddet begyndte den 16. marts, nu nærmer sig 10 millioner m ³ , som vist i grafen nedenfor. I tidligere hændelser begyndte magma at udbrede sig som digetrusioner fra reservoiret i 4-5 km dybde mod overfladen, da en tærskel på omkring 8-13 millioner m ³ genopladet magma blev nået.

Grafen viser den estimerede mængde magma, der er blevet genopladet under Svartsengi-området mellem vulkanudbrud eller magmaudbredelse, der har fundet sted siden november 2023.

Så længe magmaen fortsætter med at akkumulere i Svartsengi-reservoiret, øges sandsynligheden for en betydelig eskalering af den eruptive aktivitet i Sundhnúk-kraterrækken.

 

• Nye eruptive sprækker kan åbne sig i området mellem Stóra-Skógfell og Hagafell og/eller den nuværende eruptive sprække kan forstørre sig på grund af en pludselig stigning i lavastrømmen, som kan ligne den indledende fase af de sidste udbrud i området. Dette kan ske med meget korte, hvis nogen, forstadier.
• Det er også muligt, at hvis mere magma begynder at udbrede sig fra Svartsengi-reservoiret til Sundhnúks-kraterrækken, kan dette ske gradvist, indtil en balance mellem indstrømningshastigheden i dybden og ekstruderingshastigheden ved overfladen er nået.

 

Der er også mulighed for et nyt digeindbrud, der resulterer i, at en ny vulkansk sprække åbner sig andre steder end i området mellem Stóra-Skógfell og Hagafell. Dette scenario anses for at være mindre sandsynligt end de andre, og længere og mere intense forstadier forventes at forekomme.

Onsdag den 24. april foretog eksperter fra det islandske meteorologiske kontor målinger af gasudslip fra udbruddet. Det blev estimeret til at være 6-9 kg/s SO ₂ , hvorimod ved den sidste måling, der blev foretaget for to uger siden den 12. april, blev gasudledningen estimeret til 10-18 kg/s. Dette er ikke en bekræftelse af, at tendensen i gasudledning fra udbruddet er aftagende. Faktisk, mens udbruddet fortsætter, kan emissionerne af SO ₂ variere meget mellem dage (som det blev observeret under udbruddene ved Fagradalsfjall). Der er fortsat en fare på grund af gasudledning i området omkring krateret samt i bosættelser på Reykjanes-halvøen, og vi råder folk i området til at overvåge luftkvaliteten og sætte sig ind i reaktionen på luftforurening fra udbruddet.

 

Vulkangasforurening (SO ₂ ) i atmosfæren var tydeligt synlig på et satellitbillede (Sentinel 5p) taget i går, 25. april kl. 14:27 UTC.

Vejrudsigten forudser nordlige vinde på 5-10 m/s i dag, fredag, og gasforurening vil blive spredt syd for udbrudsstedet og kunne mærkes i Grindavík. Vejrudsigten for gasspredning er her .

 

Opdateret 23. april kl. 18:00 UTC

 

Udbruddet fortsætter fra den enkelte udluftning, som er dannet lige øst for Sundhnúkur, på lignende måde siden 5. april. Lava fortsætter med at ekstrudere og forplante sig mod syd langs åbne kanaler, som er tydeligt synlige fra kameraerne. Lavaen rejser også længere afstande fra krateret gennem et netværk af lukkede rør, som forhindrer lavaen i at afkøle ved direkte kontakt med atmosfæren. Sektoren af ​​lavafeltet, som har forplantet sig mod syd og nået de beskyttende barrierer, der er bygget øst for Grindavík by, er blevet tykkere i de seneste par dage, som vist på billederne nedenfor. Billederne viser forskellene i lavamarkens profil mellem 18. og 23. april. Billedet øverst er taget fra kameraet ejet af den islandske civilbeskyttelse, som er placeret ved barrieren øst for Grindavík og ser ud mod den del af lavafeltet, som forplantede sig mod Suðurstandavegur i begyndelsen af ​​udbruddet. Billedet nederst er også fra et kamera ejet af den islandske civilbeskyttelse, og det er placeret på toppen af ​​Hagafell-bakken og er orienteret mod syd. 

Estimater af lavaekstruderingshastigheden viser værdier mellem 3-4 m3/s siden begyndelsen af ​​april. De sidste målinger blev foretaget den 15. april, så vi afventer nu nye opkøb, som vil være tilgængelige i næste uge, for at belyse niveauet af den aktuelle aktivitet og for at forstå, om der er sket væsentlige ændringer.

Billede fra kameraet, ejet af den islandske civilbeskyttelse, som er placeret ved den beskyttende barriere øst for Grindavík by. Kameraet er orienteret til at følge lava-tungen, som forplantede sig mod Suðurstrandavegur i begyndelsen af ​​udbruddet. Den gule boks angiver, hvor lavafeltet har tyknet mest de seneste dage.

Billede fra kameraet, ejet af den islandske civilbeskyttelse, som ligger på toppen af ​​Hagafell-bakken og er orienteret mod syd. Den gule boks angiver, hvor lavafeltet tæt på den potentielle barriere har tyknet mest i løbet af de seneste par dage.

Jordhævningen målt omkring Svartsengi-regionen fortsætter, hvilket indikerer, at magma akkumuleres i dybden med en stabil hastighed, og den samlede tilstrømning til reservoiret er større end den udstrømning, der føder udbruddet. Ved at bruge analytiske modeller, begrænset af både GNSS- og InSAR-data, vurderes det, at mellem 7-8 millioner m3 magma er blevet genopladet til Svartsengi-reservoiret siden udbruddet startede den 16. marts. I tidligere hændelser begyndte magma at udbrede sig som digeindtrængninger fra reservoiret i 4-5 km dybde mod overfladen, da en tærskel på omkring 8-13 millioner m3 genopladet magma blev nået.

Så længe magmaen fortsætter med at akkumulere i Svartsengi-reservoiret, øges sandsynligheden for en betydelig eskalering af den eruptive aktivitet i Sundhnúk-kraterrækken. 

 

• Nye eruptive sprækker kan åbne sig i området mellem Stóra-Skógfells og Hagafells, og/eller den nuværende eruptivåbning kan forstørre sig på grund af en pludselig stigning i magmastrømningshastigheden, som kan nå niveauer, der kan sammenlignes med dem, der blev observeret i begyndelsen af ​​de sidste fire udbrud, som sket i området. Hvis dette sker, forventes meget korte forstadier, hvis nogen, er. 
• Det er også muligt, at hvis mere magma begynder at udbrede sig fra Svartsengi-reservoiret til Sundhnúks-kraterrækken, kan dette ske gradvist, indtil en balance mellem indstrømningshastigheden i dybden og ekstruderingshastigheden ved overfladen er nået.

 

Der er også mulighed for, at en ny digeindtrængning vil resultere i åbning af yderligere eruptive sprækker i andre områder end mellem Stóra-Skógfells og Hagafells. Dette scenarie anses dog for at være mindre sandsynligt end de tidligere nævnte, og hvis dette sker, forventes der at forekomme længere og mere intense prækursorer. 

Opdateret farekort

Under det videnskabelige møde i morges blev farevurderingen for den igangværende aktivitet gennemgået. Sandsynligheden for åbning af eruptive sprækker i Zone 1 (Svartsengi), Zone 4 (Grindavík) og Zone 7 er reduceret fra at være betydelig til lav. 

Fredag ​​i sidste uge, på grund af den fortsatte inflation af Svartsengi-reservoiret, og den høje usikkerhed omkring denne nye situation og mulige udfald, blev det besluttet midlertidigt at øge sandsynligheden for udbrudsåbninger i disse områder. Efter mødet i dag er det dog aftalt, at der på nuværende tidspunkt ikke er evidens for øget sandsynlighed for udbrudsåbninger i disse områder. 

Mens udbruddet fortsætter, vurderes det, at hvis der opstår en øget magmastrøm, vil magmaen højst sandsynligt følge de åbne baner, der fodrer det nuværende udbrud, og/eller nye eruptive sprækker kan dannes i nærheden. Af denne grund vurderes sandsynligheden for udbrudsåbninger uden varsel stadig at være meget høj inden for Zone 3 (Sundhnúks kraterrække), som forbliver uændret.

 

Opdateret 19. april kl. 15:30 UTC

• Jordløftet i Svartsengi fortsætter i et jævnt tempo.

• Siden 5. april er der kun gået et krater i udbrud, og lavastrømmen fra det har siden holdt sig forholdsvis stabil, godt 3 m ³ /s.

• Fortsat fare på grund af gasemissioner. Folk rådes til at overvåge luftkvaliteten .

• Vejrudsigten for gasspredning er her

• Fortsat magmaakkumulering under Svartsengi med den nuværende hastighed øger sandsynligheden for endnu en magmaudbredelse i de kommende dage eller uger, på trods af det igangværende udbrud.

 

Da udbruddet startede den 16. marts, aftog jordhævningen ved Svartsengi betydeligt og stoppede næsten. Dette indikerede en ligevægt mellem indstrømning af magma til magma-reservoiret under Svartsengi og til overfladen ved Sundhnúkur-kraterrækken (Figur 1).

I begyndelsen af ​​april begyndte jordløftningen at stige igen, og en tilsvarende mængde magma er nu ved at bryde ud ved Sundhnúkur, som der er ophobet i reservoiret under Svartsengi, hvilket forårsager øget magmatryk (Figur 2).  

Den nuværende udvikling er ny, som er et igangværende vulkanudbrud med en forholdsvis stabil lavastrøm ved Sundhnúkur kraterrække samtidig med, at jorden løfter sig i Svartsengi. Derfor er der mere usikkerhed nu end tidligere om eventets mulige udvikling.

(Billede 1)

 

(Billede 2)

 

Modelberegninger tyder på, at over 6 millioner m ³ magma nu er blevet tilføjet magma-reservoiret under Svartsengi siden 16. marts. I tidligere hændelser har magma forplantet sig fra Svartsengi, når mellem 8 og 13 millioner m ³ er blevet tilføjet reservoiret siden sidste hændelse.

Grafen viser den estimerede mængde magma, der er blevet tilføjet under Svartsengi mellem vulkanudbrud og magma-udbredelse, der har fundet sted siden november 2023.

Mere usikkerhed omkring udviklingen af ​​aktiviteten de næste dage eller uger.

Hidtil har den generelle tendens i Sundhnúkur-området været øget sandsynlighed for magmaudbredelse og endda et efterfølgende udbrud. Nu ser det imidlertid ud til, at en ny situation er ved hånden, når en magma-udbredelse kan forekomme under et igangværende udbrud. Lad os huske på, at magma-udbredelse er en pludselig og stor strøm af magma, der forplanter sig ud af et magma-reservoir og kan kulminere med, at magma når overfladen. Efter magmaudbredelsen den 2. marts, som ikke endte med et udbrud, markerede en ændring i aktiviteten, der siden december havde været noget cyklisk.

Hvis magma-akkumulering fortsætter med en lignende hastighed, øges sandsynligheden for en anden magma-udbredelse i de kommende dage eller uger, selvom et udbrud stadig er i gang. Magmaudbredelse fra reservoiret under et igangværende udbrud er indtil videre ikke set før i området. Derfor er der mere usikkerhed om udviklingen af ​​aktiviteten i de næste dage eller uger.

Sandsynligt scenarie, hvis magmaudbredelse falder sammen med det aktuelle udbrud:

 

• Magma forplanter sig fra magma-reservoiret under Svartsengi til Sundhnúkur-kraterrækken, som det er sket i de sidste seks gange.
• Efter magma-udbredelsen kunne nye eruptive sprækker åbne sig i området mellem Stóra-Skógfell og Hagafell og/eller det nuværende eruptive krater kunne blive forstørret på grund af en pludselig stigning i lavastrømmen. Dette kan ske med meget kort eller ingen varsel.
• Hvis magmaudbredelsen resulterer i, at nye vulkanske sprækker åbner sig andre steder over magmadiget, som blev dannet den 10. november, forventes der meget længere varsel, højst sandsynligt intens seismisk aktivitet, deformation og trykændringer i borehuller.
• Det er også muligt, at magma-udbredelse ikke vil forekomme, men at strømningen af ​​det nuværende udbrud holder op med at falde og begynder at stige støt, indtil en ny ligevægt mellem indstrømningen af ​​magma nedefra og strømning til overfladen fra krateret er nået.
• Men hvis magma-udbredelsen resulterer i, at en ny eruptiv sprække åbner sig andre steder end i området mellem Stóra-Skógfell og Hagafell, vil et sådant scenarie højst sandsynligt blive ledsaget af intens seismicitet og deformation med betydeligt mere varsel end tidligere udbrud.

Opdateret farevurdering

I lyset af usikkerheden forårsaget af stigende tryk i magma-reservoiret under Svartsengi har det islandske meteorologiske kontor øget faren på grund af mulig åbning af eruptive sprækker i zone 1, 4 og 7 fra “lav” til “betydelig”

Den overordnede fare (farve) i de berørte zoner ændres dog ikke.

(klik på billedet for at se det større)

 

Opdateret 18. april kl. 16:00 UTC

• Lavafeltet dækker nu 6,15 km ² og rumfanget er 33,2 ± 0,8 millioner m ³ .

• Gennemsnitlig lavastrøm fra krateret i perioden 8.-15. april er estimeret til 3,2 ± 0,2 m ³ /s.

• Jordløftet i Svartsengi fortsætter i et jævnt tempo.

• Fortsat fare på grund af gasforurening. Folk i området rådes til at tjekke luftkvaliteten .

• Vejrudsigten for gasdistribution i dag (torsdag) er nordvestlig vind, 3-8 m/s, med gasudledning mod sydøst. Følg gasspredningsprognosen her .

 

Udbruddet ved Sundhnúkur-kraterrækken fortsætter, og et krater lige øst for Sundhnúkur er fortsat i udbrud. Lavafeltet fortsætter med at bygge op tæt på kraterne. Lavaen flyder også i lukkede kanaler omkring 1 km mod sydøst, og der er aktive områder i lavafeltet nord for Hagafell.

Mandag den 15. april gennemførte forskere fra det islandske naturhistoriske institut (IINH) og National Land Survey of Iceland (NLSI) en overvågningsflyvning over udbrudsområdet for at indhente billeder til lavakortlægning ved fotogrammetri. Resultaterne fra overvågningsflyvningen viser, at arealet af lavafeltet den 15. april målte 6,15 km ² og volumenet 33,2 ± 0,8 millioner m ³ . Lavastrømningsfeltet og tykkelsen af ​​det er vist på kortet nedenfor.

Kort, der viser lavastrømningsområdet og tykkelsen af ​​lavaen dannet i det igangværende udbrud. Lilla farver viser lava dannet i området siden december 2023.

Den gennemsnitlige lavastrøm fra krateret i perioden 8.-15. april er estimeret til 3,2 ± 0,2 m ³ /s. Dette er en lille ændring i forhold til den gennemsnitlige lavastrøm i perioden 3.-8. april, som blev estimeret til 3,6 ± 0,7 m ³ /s. Resultatet af tidligere måling fra IINH og NLSI fotogrammetri-teamet kan ses i tabellen nedenfor.

Fra	Til	Gennemsnitlig lavastrøm i perioden (m 3 /s)	Areal   (km 2 )	Bind (millioner m 3 )	Gennemsnitlig tykkelse af lavafeltet (m)
16. mar.2024	17. mar.2024	234 ± 9	5,72	18,1 ± 0,8	3,2 ± 0,1
17. mar.2024	20. mar.2024	14,5 ± 0,6	5,58	20,9 ± 0,5	3,7 ± 0,1
20. mar.2024	27. mar.2024	7,8 ± 0,7	5,99	25,7 ± 1,9	4,3 ± 0,3
27. mar.2024	3. apr. 2024	6,6 ± 0,3	6,13	29,7 ± 1,7	4,8 ± 0,3
3. apr. 2024	8. apr. 2024	3,6 ± 0,7	6,14	31,3 ± 2,4	5,1 ± 0,4
8. apr. 2024	15. apr. 2024	3,2 ± 0,2	6,15	33,2 ± 0,8	5,4 ± 0,1

 

 

Jordløftet i Svartsengi fortsætter i et jævnt tempo. Dette indikerer, at omkring halvdelen af ​​magmaen, der stiger op fra dybden, akkumuleres i magmareservoiret, mens den anden halvdel bryder ud til overfladen ved Sundhnúkur-kraterrækken.

Forskydninger på GPS-stationen SENG i Svartsengi siden 11. november 2024 mod nord, øst og lodret (top, midt, bund). Den nederste kurve viser jordløft i millimeter, og gårsdagens (17. april) måling er vist med en grøn prik. De røde lodrette linjer er tidspunktet for de sidste fire udbrud (18. december 2023, 14. januar, 8. februar og 16. marts 2024), og de blå linjer viser indtrængen af ​​magmadiget, der er sket i Sundhnúkur kraterrækkeområdet uden at resultere i et udbrud (10. november 2023 og 2. marts 2024).

 

Der er fortsat en fare på grund af gasemissioner fra udbruddet, som kan forårsage forurening i bosættelser på Reykjanes-halvøen, og vi råder folk i området til at overvåge luftkvaliteten og sætte sig ind i reaktionen på luftforurening fra udbrud.

Vejrudsigten for gasdistribution i dag (torsdag) er nordvestlig vind, 3-8 m/s, med gasudledning mod sydøst. I morgen (fredag) blæser der sydøst 8-13 m/s med regn. Mere sydlig vind om aftenen. Gasforureningen vil gå mod nordvest i løbet af dagen og senere mod nord. Følg gasspredningsprognosen her .

 

Opdateret 16. april kl. 18:00 UTC

• Farevurderingen er blevet opdateret. Den samlede fare for Grindavík (Zone 4) skønnes at være betydelig (orange).
• Landhævningen ved Svartsengi fortsætter, og hævningshastigheden har været konstant siden begyndelsen af ​​april.
• Fortsat fare på grund af gasforurening. Folk i området rådes til at tjekke luftkvaliteten .
• Gasspredningsprognosen kan findes her .
• Et krater, der ligger øst for Sundhnúkur, er fortsat aktivt.

 

Udbruddet ved Sundhnúkur- kraterrækken fortsætter og har nu varet i en måned, hvilket var emnet for en nyhedsrapport offentliggjort tidligere i dag. Et krater, som ligger lige øst for Sundhnúkur, fortsætter med at bryde ud. Lava flyder stadig syd for krateret, men strækker sig ikke langt, så lavafeltet fortsætter med at bygge op nær krateret. Der er et aktivt lavafelt i nærheden af ​​Hagafell, som det kan ses på et billede fra det islandske meteorologiske kontors webkamera placeret ved Þorbjörn.

Billede fra det islandske meteorologiske kontors webcam, taget kl. 05.10 den 16. april. Webkameraet er placeret på toppen af ​​Þorbjörn og ser mod øst mod udbrudsstedet. Krateret er i midten af ​​billedet, og lava strømmer ud fra det. Foran krateret er Sundhnúkur, og på højre side af billedet er Hagafell og lavastrømsfronter.

Seismisk aktivitet har været forholdsvis rolig nær udbrudsstedet siden begyndelsen af ​​udbruddet, indtil en lille jordskælvssværm begyndte ved Lágafell efter middag den 14. april. Den seismiske sværm varede over 4 timer og har været forbundet med spændingsændringer i skorpen på grund af land. løft i Svartsengi. Seismisk aktivitet fortsætter i de vestlige skråninger af Fagradalsfjall i 6-8 km dybde og har været i gang siden urolighederne i Sundhnúkur-området i løbet af de sidste 4 måneder.

Landhævningen fortsætter og har været i et stabilt tempo siden begyndelsen af ​​april. Modelberegninger baseret på GPS-data indikerer, at tilstrømningen af ​​magma til magma-reservoiret er omkring halvdelen af, hvad den var før begyndelsen af ​​udbruddet den 16. marts. Dette indikerer, at omkring halvdelen af ​​magmaen, der kommer fra dybden, ophobes i magmaen. reservoir, mens den anden halvdel er udbrudt til overfladen.

I begyndelsen af ​​april begyndte landhævningshastigheden at stige. I øjeblikket bryder en lignende mængde magma ud på overfladen og akkumuleres også i magmakammeret under Svartsengi, hvilket forårsager en trykstigning i magmakammeret.

Der er fortsat risiko for gasemissioner fra udbruddet, som kan forårsage luftforurening i bosættelser på Reykjanes-halvøen, og vi råder folk i området til at overvåge luftkvaliteten og sætte sig ind i symptomer og reaktioner relateret til luftforurening fra udbruddet. .

Vejrudsigten i dag (tirsdag) er en langsom vind, variabel retning. Der kan således samle sig gas i nærheden af ​​udbrudsstedet. I nat vil der vinde sydøstlig 10-15 m/s, med gasudledning nordvest mod Reykjanesbær. Vest- og nordvestlig vind ventes at blive 3-10 m/s i morgen tidlig, og sprede gas øst og sydøst mod Þorlákshöfn. Følg gasspredningsprognosen her .

Farevurdering

Farevurderingen er blevet opdateret og er gældende fra kl. 15:00 i dag til den 23. april med forbehold for udvikling. Farevurderingen er ændret, således at faren på grund af lavastrømme er blevet sænket i alle områder undtagen i zone 3 (Sundhnúkur kraterrækken) og zone 6. Denne ændring foretages, fordi der ikke har været en aktiv lavastrøm i de øvrige områder. i de sidste to uger. Baseret på den aktuelle aktivitet i udbruddet vurderes det, at lava sandsynligvis ikke vil strømme langt fra krateret og ind i andre farezoner. Denne ændring betyder, at den samlede fare i Zone 4 (Grindavík) nu vurderes som betydelig (orange) i stedet for høj (rød). Den samlede fare i andre områder forbliver uændret. Faren fra gasemissioner vurderes fortsat som høj i alle områder undtagen ved Sundhnúkur kraterrækkeområdet (zone 3), hvor den vurderes at være meget høj. Faren i Zone 4 (Grindavík) og Zone 6 vurderes fortsat som høj på grund af synkehuller og fejlbevægelser.

(Klik på billedet for at se det større)

 

Opdateret 15. april kl. 17:30 UTC

• Vulkanudbruddet, der begyndte den 16. marts, er stadig i gang.

• Stigningen fortsætter i samme takt siden starten af ​​april.

• Farevurderingen er gældende indtil 16. april, medmindre situationen ændrer sig.

• Risikoen for gasemissioner er fortsat betydelig. Folk i området bliver mindet om at overvåge luftkvaliteten.

• Gasspredningsprognosen kan findes her

 

Lige efter middag i går begyndte en lille jordskælvsværm nær Lágafell, lige nordvest for Grindavík. Den sluttede omkring halv fire om eftermiddagen. Sværmen bestod af cirka 90 jordskælv, hvor den mest intense aktivitetsperiode var 35 jordskælv mellem kl. 13.00 og 14.00. Alle jordskælv var under størrelsesordenen 1, og de fleste var på dybder på cirka 2-4 km. Denne lille jordskælvsværm skyldtes sandsynligvis stressændringer i jordskorpen på grund af igangværende landstigning i Svartengi, som diskuteret i gårsdagens nyhedsopdatering.

Vedhæftet er en figur, der viser placeringen af ​​jordskælvene på et kort, og derunder er en graf, der viser deres dybde. Panelet øverst til højre viser jordskælvets størrelse i regionen fra middag til aften i går. Panelet i midten til højre viser det samlede antal jordskælv, mens det nederste panel viser antallet af jordskælv i timen. Som grafen viser, blev der registreret flere små jordskælv i området i går eftermiddags, men der har ikke været nogen seismisk aktivitet i regionen siden midnat i dag.

Foto taget onsdag den 10. april, der viser den aktive udluftning set fra Sundhnúkur. (Foto: Jón Bjarni Friðriksson/Island Meteorologisk Kontor). Klik på billedet for at se det større.

 

Opdateret 14. april kl. 18:00 UTC

• Vulkanudbruddet, der begyndte den 16. marts, er stadig i gang.

• Stigningen fortsætter i samme takt siden starten af ​​april.

• Farevurderingen er gældende indtil 16. april, medmindre situationen ændrer sig.

• Risikoen for gasemissioner er fortsat betydelig. Folk i området bliver mindet om at overvåge luftkvaliteten.

• Gasspredningsprognosen kan findes her.

 

Adskillige små jordskælv (under styrke 1) er blevet detekteret nordvest for Grindavík i de sidste par timer. (Se figurerne nedenfor.) Denne seismiske aktivitet er fokuseret nær diget, der blev dannet den 10. november og er sandsynligvis relateret til jorddeformationen i Svartsengi, som påvirker regionens trykregime.

Dagens seismiske aktivitet kan sammenlignes med aktiviteten målt i dette område i midten af ​​marts sidste år. Derfor tyder den seismiske aktivitet ikke på ændringer i det igangværende vulkanudbrud, som har holdt sig relativt stabilt i weekenden. Den seismiske aktivitet nordvest for Grindavík tyder heller ikke på, at magma bevæger sig under dette område.

I skrivende stund er den seismiske aktivitet nordvest for Grindavík lidt aftaget. Det er usandsynligt, at store jordskælv vil ledsage denne nuværende aktivitet.

Skulle magma afvige fra sin nuværende rute, der kommer til overfladen ved Sundhnúkur-kraterrækken, og i stedet vælge en alternativ sti, såsom at gå mod vest mod Eldvörp eller syd for Þorbirnir, vil forløberen for et muligt udbrud i dette område involvere meget intens seismisk aktivitet og jord. deformation, der er tydeligt synlig på instrumenter og satellitbilleder. I øjeblikket er der ingen sådanne tegn på nuværende tidspunkt.

Det islandske meteorologiske kontor fortsætter sin 24-timers overvågning af området for at overvåge udbrudsstedet.

Denne figur viser seismisk aktivitet fra den 9. marts til i dag den 14. april. De sorte streger repræsenterer de ydre grænser for de grabene, der er dannet i forbindelse med den betydelige digeindbrud den 10. november 2023 og udbruddet den 14. januar i år. De fleste af jordskælvene i dag har været mindre end 1. Blå cirkler repræsenterer jordskælv, der fandt sted fra 9. til 14. marts, mens røde cirkler repræsenterer jordskælv, der fandt sted i dag, 14. april. Jordskælvene er placeret på den vestlige kant af lavningen dannet i november 10.

I området nordvest for Grindavík er der en række kendte forkastninger med nord-syd orientering, som er dannet, da diget indtrængen skete den 10. november. Derfor er dagens jordskælv også tegn på spændingsudløsning langs disse forkastninger på grund af landhævningen i Svartsengi.

 

Opdateret 12. april kl. 14:15 UTC

• Vulkanudbruddet, der begyndte den 16. marts, er stadig i gang.
• Landstigningen fortsætter i samme takt siden starten af ​​april.
• Farevurderingen er gældende indtil 16. april, medmindre situationen ændrer sig.
• Risikoen for gasemissioner er fortsat betydelig. Folk i området bliver mindet om at overvåge luftkvaliteten .
• Gasspredningsprognosen kan findes her .

Udbruddet, der startede ved Sundhnúkur-kraterrækken om aftenen den 16. marts, er stadig i gang. En udluftning forbliver aktiv, som den har været siden den 5. april. Lava fortsætter med at strømme sydpå fra udluftningen, men bevæger sig ikke langt, så lavafeltet fortsætter med at bygge op nær krateret. Der er ingen synlige tegn på lava, der bevæger sig frem mod de beskyttende barrierer nord for Grindavík, Suðurstrandarvegur eller Melhólsnáma.

Landstigningen i Svartsengi fortsætter i samme takt, som steg i begyndelsen af ​​april. Dette er en hurtigere hastighed end den, der blev observeret fra begyndelsen af ​​udbruddet den 16. marts til slutningen af ​​marts . Dette indikerer, at størstedelen af ​​magmaen, der strømmer ind i reservoiret under Svartsengi, akkumuleres der, hvilket forårsager en stigning i tryk og jordløftning. Mens udbruddet fortsætter, er der stadig en åben forbindelse mellem magma-akkumuleringsområdet i Svartsengi og Sundhnúkur-kraterrækken, og en del af magmaen fortsætter med at strømme til overfladen der. Mindre ændringer i lavafeltet kan observeres mellem dage, men den samlede rate har været stabil siden begyndelsen af ​​april.

Farevurderingen forbliver uændret og gyldig indtil kl. 15.00 den 16. april. Se flere detaljer her .

Der er stadig risiko for gasemissioner fra vulkanen, som kan forårsage forurening på Reykjanes-halvøen. Folk i området rådes til at overvåge luftkvaliteten og gøre sig bekendt med symptomer på udsættelse for vulkansk gasforurening.

Et fotografi taget onsdag den 10. april, der viser det aktive krater set fra Sundhnúkur. (Foto: Jón Bjarni Friðriksson)

Opdateret 9. april kl. 17:30 UTC

• På trods af et fald i intensiteten af ​​vulkanudbruddet er der ingen tegn på, at den samlede magmastrøm fra dybden er aftagende.

• Den gennemsnitlige strømningshastighed for lavastrømmen fra åbningerne mellem 3. og 8. april er estimeret til at være 3,6 ± 0,7 m3/s.

• I morgen forventes der østlige og sydøstlige vinde, der fører gasudslip mod vest og nordvest fra udbrudsstederne. Følg gasspredningsprognosen her.

• Periodisk bliver der fortsat målt høje niveauer af SO2 omkring vulkanen og i bosættelser på Reykjanes-halvøen. Beboere opfordres til at overvåge luftkvaliteten i området.

Eksperter fra det islandske meteorologiske kontor og Landtilsynet foretog luftmålinger over udbrudsstedet i går den 8. april. Ved hjælp af de data, der er indsamlet under flyvningen, er det muligt at vurdere størrelsen af ​​lavafeltet og strømningshastigheden af ​​lava fra udbruddet. Resultaterne indikerer et konstant og væsentligt fald i intensiteten af ​​vulkanudbruddet.

Den gennemsnitlige lavastrøm fra åbningerne mellem 3. og 8. april er estimeret til at være 3,6 ± 0,7 m3/s. Baseret på data indsamlet af ingeniørfirmaet Efla den 3. april under en droneflyvning, blev den gennemsnitlige lavastrøm estimeret til at være 6,6 ± 0,3 m3/s fra 27. marts til 3. april. Lavafeltet har nået et areal på 6,14 km2 med et volumen på 31,3 millioner m3. Tidligere strømmede lavaen primært sydpå fra åbningerne, men skiftede kortvarigt mod nord søndag aften (7. april), da en åbningsvæg kollapsede, som nævnt i sidste opdatering. Som vist på det medfølgende kort, er lavaen tyknet betydeligt nær udluftningerne og lige syd for dem, hvor der er mest aktivitet i lavafeltet. Der er ingen synlige tegn på lavafremrykning mod beskyttende barrierer nord for Grindavík, Suðurstrandarvegur eller Melhólsnáma.

Kort, der viser omfanget og tykkelsen af ​​lavaen dannet i det aktuelle udbrud. Lilla områder viser lava, der har strømmet i området siden december 2023.

Jorddeformation er steget i løbet af den seneste uge

Jorddeformationen i Svartsengi fortsætter med at stige, hvilket falder sammen med et fald i intensiteten af ​​vulkanudbruddet. Dette indikerer, at størstedelen af ​​magmaen, der strømmer ind i reservoiret under Svartsengi, akkumuleres der, hvilket forårsager en stigning i tryk og jordløftning. Mens udbruddet fortsætter, er der stadig en åben forbindelse mellem magma-akkumuleringsområdet i Svartsengi og Sundhnúkur-kraterrækken, og en del af magmaen fortsætter med at strømme til overfladen der.

Seismisk aktivitet i diget nær Grindavík er forblevet meget lav og er fokuseret mellem Sýlingarfell og Stóra-Skógafell, med let seismicitet i det vestlige Grindavík. Seismisk aktivitet nær Fagradalsfjall, som har været vedvarende den seneste måned, er i gang og er fortsat lokaliseret på dybder på omkring 6-7 km.

Gasmålinger udført i går, den 8. april, estimerer en svovldioxid (SO2) emission på 10-18 kg/s fra ventilationsåbningerne. Periodisk bliver der fortsat målt høje niveauer af SO2 omkring vulkanen og i bosættelser på Reykjanes-halvøen. Gasemissioner fra udbruddet vil sandsynligvis forårsage forurening på Reykjanes-halvøen, og beboere rådes til at overvåge luftkvaliteten og gøre sig bekendt med symptomer relateret til luftforurening fra udbruddet.

Ifølge vejrudsigten forventes der i dag nordlige vinde, der fører gasudslip mod syd. Langsom, varierende vind om eftermiddagen kan resultere i gasforurening nær udbrudsstederne. I morgen forventes østlige og sydøstlige vinde, der fører gasudslip mod vest og nordvest. Følg gasspredningsprognosen her.

Uændret risikovurdering

Farevurderingen er blevet opdateret og er gyldig fra kl. 15:00 i dag til den 16. april, medmindre situationen ændrer sig. Der er ingen ændringer i farevurderingen, og risikoen for gasforurening er fortsat høj i alle områder undtagen omkring Sundhnúkur-kraterrækken (Zone 3), hvor den vurderes at være meget høj. Risikoen i Zone 4 (Grindavík) og Zone 6 er fortsat høj på grund af jordskælv, jorddeformation, lavastrømme og gasforurening.

(Klik på billedet for at se det større)

På trods af faldet i intensiteten af ​​vulkanudbruddet er der ingen tegn på, at den samlede magmastrøm fra dybden ind i Svartsengi-reservoiret er aftagende. Dette refererer til det samlede volumen af ​​magma, der akkumuleres under Svartsengi, ud over den magma, der strømmer mod overfladen i det nuværende udbrud ved Sundhnúkur-kraterrækken. Det er svært at forudsige, hvornår dette udbrud vil ende; den kan fortsætte i en længere periode med jævn strøm eller ophøre i den nærmeste fremtid. Efterhånden som magma fortsætter med at akkumulere under Svartsengi, og trykket stiger, er der stadig en mulighed for, at udbruddets intensitet kan stige igen, svarende til begivenhederne ved Fagradalsfjall i 2021. Hvis udbruddet snart ophører, vil magmaakkumulering sandsynligvis fortsætte under Svartsengi, og en række begivenheder svarende til det, der er observeret i den seneste måned, kan gentages.

Opdateret 8. april kl. 16:30 UTC

• Vulkanudbruddet fortsætter. En udluftning er aktiv.
• Landet har rejst sig i Svartsengi cirka 2-3 cm mellem 2. og 7. april.
• Der blev målt minimale gasudledninger i weekenden, men periodisk kan der stadig påvises høje niveauer af svovldioxid omkring vulkanen og i bebyggelser på Reykjanes-halvøen. Beboere opfordres til at overvåge luftkvaliteten i området.
• Dagens vejrudsigt indikerer en nordøstlig vindretning, hvilket får gasudledningen til at drive sydvestover over områder inklusive Grindavík. Der forventes østlige vinde i morgen den 9. april, og gasudledninger forventes at rejse mod vest fra udbrudsstederne. Følg gasspredningsprognosen her.

Udbruddet ved Sundhnúkur-kraterrækken fortsætter, med en udluftning nu aktiv. I går strømmede lava fra udluftningen sydpå i en begrænset strøm, hvilket resulterede i en storslået flod af lava. I mellemtiden steg overfladeniveauet af lava i krateret gradvist, indtil det næsten var fyldt. Den nordlige væg af udluftningen kollapsede omkring klokken 21:30 i går aftes, hvilket fik lavaen til at flyde nordpå. I dag, den 8. april, har lavastrømmen for det meste genoptaget sin sydlige retning. Lavaen, der rykker frem mod nord, som observeret i går aftes og natten over, ser ud til at være standset på bjergsiden. Krateret fortsætter med at fyldes op.

Seismiske målinger nær udbrudsstedet viser vulkansk tremor, der udviser stærke frekvenser mellem 1 og 2 Hz (grøn kurve på grafen); en stigning i styrken af ​​denne tremor svarer til lavaens maksimale strøm fra udluftningen. Efter sammenbruddet af udluftningsvæggen ser den seismiske aktivitet ud til at falde igen. Lignende seismisk aktivitet blev observeret under det nylige vulkanudbrud i Geldingadalur, hvor den seismiske aktivitet steg, efterhånden som lavaproduktionen blev intensiveret.

Hævningen er steget en smule i Svartsengi, og baseret på GPS-målinger og syntetiske blænderadarbilleder er landet steget med 2-3 cm fra 2. til 7. april. Det er dog mindre end jorddeformationen målt efter det forrige udbrud i sidste måned. Øget stigning kunne tyde på, at magma, der strømmer ind i Svartsengi, er steget, eller at der har været en opbremsning i strømmen af ​​magma mod det nuværende udbrudssted.

Minimale gasemissioner er blevet opdaget på gasmonitorer, der drives af Miljøstyrelsen i Island (UST) og det islandske meteorologiske kontor i weekenden, men periodisk kan der stadig detekteres høje niveauer af svovldioxid omkring vulkanen og i bebyggelser på Reykjanes-halvøen. Beboerne bliver mindet om at overvåge luftkvaliteten på USTs luftkvalitetshjemmeside loftgæði.is

Dagens vejrudsigt indikerer en nordøstlig vindretning, hvilket får gasudledningen til at drive sydvestover over områder inklusive Grindavík. Der forventes østlige vinde i morgen den 9. april ^, så gasudslip kan forventes at drive vestpå fra udbrudsstederne. Den seneste gasspredningsprognose kan følges her.

Opdateret 4. april kl. 17:00 UTC

Udbruddet ved Sundhnúkur-kraterrækken fortsætter, og to kratere er stadig aktive som de seneste dage. Det nordlige krater er større, og det meste af lavastrømmen ser ud til at være udbrudt fra det, som det kan ses på billedet nedenfor, som blev taget i nat, den 3. april. Lava fortsætter med at strømme sydpå fra kraterne på toppen af ​​lavafeltet, der blev dannet i de første par dage af dette udbrud. I aftes var der ingen tydelige tegn på lavastrømning langs lavabarriererne nord for Grindavík, Southcoast road eller Melhólsnáma-minen.

Luftbillede fra en droneflyvning opereret af Civil Protection i aftes den 3. april. Billedet viser de to kratere og lavaen, der strømmer fra dem mod syd.

Et interferogram, der dækker perioden 18. marts – 3. april, viser, at landet har hævet sig omkring 3 cm i Svartsengi i den tid. Dette er en betydeligt langsommere deformation, der blev målt forud for de udbrud og digeudbredelser, der har fundet sted i de sidste måneder. Data fra GPS-målinger i samme periode tyder på, at hastigheden af ​​landhævningen har varieret, men det er vanskeligt at estimere dag-til-dag deformation baseret på disse data. I betragtning af GPS-dataene for samme tidsperiode som interferogrammet (18. marts – 3. april), er de to datasæt konsistente. Landhævning påvises i Svartsengi under udbruddet, hvilket ikke er set i de begivenheder, der tidligere har fundet sted på Sundhnúkur-kraterrækken. Dette indikerer, at systemet er åbent, og magma fortsætter med at strømme fra betydelig dybde under Svartsengi til overfladen i Sundhnúkur-kraterrækken. 

Interferogram (InSAR) viser deformation fra 18. marts – 3. april. Gule og orange farver viser områder omkring Svartsengi, hvor landhævning registreres.

Gasmålinger gennemført sidste tirsdag den 2. april anslår, at ca. 37-41 kg/s SO ₂ udsendes fra kraterne. Midlertidigt høje svovldioxidniveauer bliver fortsat målt omkring udbrudsstedet og i kommuner på Reykjanes-halvøen. Gas fra udbruddet vil sandsynligvis forårsage forurening på Reykjanes-halvøen, og vi råder folk i området til at overvåge luftkvaliteten på loftgaedi.is og sætte sig ind i reaktionen på luftforurening fra vulkanudbrud.

Vejrudsigten i dag (torsdag) er sydøstlige og sydlige vinde på 8-13 m/s på udbrudsstedet, hvilket medfører, at gas spredes mod nordvest og nord, hvilket betyder, at der kunne detekteres gas i Vogar, Reykjanesbær og Suðurnesjabær. Østlig vind 5-10 m/s i morgen (fredag), hvilket forårsager gasspredning mod vest, for eksempel til Svartsengi. Nordvestlig vind, 5-10 m/s sent i morgen forårsager gasforurening i sydvest og muligvis i Grindavík.

Gasdistributionsprognose er her .

Farevurdering offentliggjort den 2. april forbliver uændret og er gyldig indtil 9. april med forbehold for udvikling.

Opdateret 2. april kl. 17:30 UTC

• Udbruddet fortsætter, og to kratere er nu aktive. Inflation er ikke blevet opdaget i de sidste par dage.

• På det seneste er der opstået vegetationsbrande omkring lavafeltet, og det er en løbende risiko, mens vejret er tørt.

• Gasforurening er spredt mod sydvest og senere mod vest og vil sandsynligvis blive opdaget lejlighedsvis i Grindavík og muligvis i Hafnir. Gasdistributionsprognose og luftkvalitet kan overvåges.

• Lavakanterne har nået betydelige højder og kan være ustabile.

• Farevurdering uændret.

 

Udbruddet ved Sundhnúkur-kraterrækken fortsætter, og to kratere er nu aktive. Det tredje krater, som var meget mindre end de to andre, blev slukket i påsken. Vulkanskælven forbliver stabil.

Inflation i Svartsengi er ikke blevet opdaget i de seneste dage, hvilket indikerer, at mindre magma ophobes i magma-reservoiret under Svartsengi, og i stedet strømmer mod kraterne, hvor det bryder ud. Der kan opnås en balance mellem tilstrømningen af ​​magma til Svartsengi-reservoiret og udbrudskratere, men geokemiske undersøgelser kan bekræfte dette i fremtiden.

Eksperter fra National Land Survey of Iceland har behandlet satellitdata fra den 27. marts, der viser, at lavafeltet dengang var 5,99 km2 og lavaens volumen siden begyndelsen af ​​udbruddet var 25,7 ± 1,9 millioner m3. Den gennemsnitlige ekstruderingshastighed af lava fra kraterne blev estimeret til 7,8 ± 0,7 m3/s, hvilket er meget sammenligneligt med ekstruderingshastigheden under den første fase af Geldingadalir-udbruddet i 2021. Målet er at tage luftfotos af området i kommende dage for at få opdaterede ekstruderingsrater siden 27. marts, hvilket vil give yderligere indsigt i udviklingen af ​​den eruptive aktivitet. Det følgende kort viser lavastrømningsfeltet og dets tykkelse, som det var den 27. marts.

Kort, der viser strømningsfeltet og tykkelsen af ​​lavaen dannet under det igangværende udbrud. Lilla lag viser lavaer, der er dannet i området siden december 2023.

Vegetationsbrande omkring lavamarken

På det seneste er der opstået vegetationsbrande omkring lavafeltet, og det er en løbende risiko, mens vejret er tørt.

Lavakanterne har nået betydelige højder og kan være ustabile, pludselige og hurtige lavaudbrud kan opstå, hvis nye lavalapper bryder ud fra kanten af ​​en lavarand.

I de seneste dage er der lejlighedsvis påvist høje niveauer af svovlbrinte i Grindavík. Vejrudsigten i dag (tirsdag) er nordøstlig og senere østlig vind 5-13 m/s på udbrudsstedet. Gasforurening er derfor spredt mod sydvest og senere mod vest, og vil sandsynligvis blive opdaget lejlighedsvis i Grindavík og muligvis i Hafnir. Østlige og sydøstlige vinde 3-10 m/s i morgen (onsdag), hvilket får gasforurening til at rejse mod vest og nordvest, og kan således opdages i mange dele af det vestlige Reykjanes-område, herunder Reykjanesbær. Gasdistributionsprognose er her .

Farevurdering uændret

Farevurderingen er blevet opdateret og er gældende fra kl. 15:00 i dag til den 9. april, med forbehold for væsentlige udviklinger. Der er ingen ændringer i farevurderingen, og faren fra gasforurening vurderes fortsat høj i alle områder undtagen ved Sundhnúkur kraterrækkeområdet (zone 3), hvor den vurderes som meget høj. Faren i zone 4 (Grindavík) og zone 6 vurderes fortsat som høj på grund af synkehuller, fejlbevægelser, lavastrømning og gasforurening.

 

Opdateret 27. marts kl. 14:00 UTC

 

• Høje niveauer af SO ₂ (Svovldioxid) blev målt i weekenden. Gasspredningsprognose kan følges her .
• Denne koncentration af SO ₂ anses for at være meget usund. Det er vigtigt at være meget opmærksom på udviklingen i luftkvaliteten.
• Vulkanudbruddet har været stabilt siden mandag den 25. marts.
  

 

 

Vulkanudbruddet har været stabilt siden mandag den 25. marts. Udbrudsrysten har været konstant siden da, ligesom aktiviteten i de tre kratere. Lava fortsætter med at strømme sydpå fra kraterne, for det meste oven på lavafeltet, der blev dannet i løbet af de første dage af udbruddet. Det følgende billede viser udvidelsen af ​​lavafeltet som ekstrapoleret fra satellitbilleder (ICEYE). Den seneste anskaffelse var den 26. marts, og den viser udvidelsen af ​​lavafeltet mod vest, syd for Hagafell, samt yderligere lavafremrykning mod øst og syd for de aktive åbninger.

Stribede områder angiver områder, hvor der skete ændringer i lavafeltet mellem den 20. og 26. marts. Den rødstribede del af området betegner et område, hvor lava ikke havde strømmet tidligere i dette udbrud. Lyslilla områder betegner områder, hvor lava strømmede fra udbrud i februar og januar.

Hævningen fortsætter i Svartsengi, men i et langsommere tempo end før tidligere udbrud eller digeindtrængninger i de seneste måneder. Dette tyder på, at magma stadig ophobes under Svartsengi på trods af igangværende udbrud. Lidt eller ingen seismisk aktivitet er blevet påvist i området.

 

Høje niveauer af SO2 målt de sidste par dage

 

Siden fredag ​​(22. marts) er der blevet installeret to yderligere stationer til at overvåge koncentrationerne af SO2 ved jorden. VÍ har i samarbejde med Almannavarnir lokaliseret dem ved Blue Lagoon og i havneområdet i Grindavík. Begge stationer streamer data til USTs hjemmeside, loftgæði.is.

Tidligt i går morges omkring klokken 03:00 afslørede stationen i BL niveauer af SO2 op til 7000 mikrogram/m3, og i morges omkring klokken 04:00 målte stationen i Grindavík (Nesvegur) koncentrationer op til 9000 mikrogram/m3. Sådanne koncentrationer betragtes som óholl, og folk anbefales at følge instruktionerne fra UST og Embætti landlæknis (link). Den 26. ^marts viste stationen i Hafnir også høje koncentrationer af SO2 op til omkring 2000 mikrogarm/m3 omkring middagstid. Mængden af ​​SO2 frigivet ved udbruddet og meteorologien i området skaber stadig betingelser for alvorlig gasforurening på halvøen.

Foto siden i morges (27. marts) fra IMO’s webcam placeret ved Hópsnes SE for Grindavík. I midten af ​​billedet er bjerget Þorbjörn og udbrudsstedet øst for det, hvor gasfanen stiger og bevæger sig mod vest på grund af østenvind.

 

Opdateret 25. marts kl. 16:30 UTC

• Høje niveauer af SO ₂ (Svovldioxid) blev målt i weekenden. Gasspredningsprognose kan følges her .
• Denne koncentration af SO ₂ anses for at være meget usund. Det er vigtigt at være meget opmærksom på udviklingen i luftkvaliteten.
• Vulkanaktiviteten ser ud til at være faldet ved Sundhnúksgíga.
• Farevurderingen forbliver uændret. Øgede farer fortsætter på grund af gasemissioner

 

Den vulkanske aktivitet ved Sundhnúksgíga ser ud til at være faldet i løbet af de sidste par dage. Aktiviteten i åbningerne er faldet og muligvis ophørt i de mindste kratere. Derudover er vulkansk tremor gradvist aftaget i løbet af de sidste par dage. Den primære lavastrøm løber mod syd fra åbningerne og bøjer derefter mod vest. I weekenden fortsatte lava med at strømme ind i Melhólsnáma og har nu fyldt den. Lavaen fortsætter dog også med at blive tykkere nær kraterne.

GPS-målinger i de seneste dage indikerer en igangværende landstigning i Svartsengi, men den udviser en langsommere hastighed end før. Dette tyder på, at magma fortsætter med at akkumulere i reservoiret under Svartsengi på trods af det igangværende udbrud.

Høje niveauer af SO2 målt de sidste par dage

Høje niveauer af SO ₂ er blevet målt i Höfn og Grindavík de seneste par dage. Denne koncentration anses for at være meget usund, og folk vil sandsynligvis opleve luftvejssymptomer, hvis de udsættes. Det er vigtigt at blive indendørs, lukke vinduer og slukke for aircondition. Dette er især vigtigt, hvor der udføres udendørs arbejde, som oplyst af arbejdssikkerhedsmyndighederne; virksomheder og institutioner i den sydvestlige del af landet skal være meget opmærksomme på den videre udvikling i luftkvaliteten på grund af den potentielle risiko for gasforurening. Folk i området rådes til at overvåge luftkvaliteten og gøre sig bekendt med symptomer på luftforurening fra vulkanske gasser.

Vejrudsigten for i dag (mandag) forudser nordøstlige vinde på 3-8 m/s ved udbrudsstederne, hvor forureningen driver sydvestover (over Grindavík og Svartsengi); gas kan samle sig i nærheden af ​​udbrudsstederne på grund af langsomme vindhastigheder. Om aftenen, natten og de tidlige morgentimer forventes der at komme vind fra øst med 8-13 m/s ved udbrudsstederne, hvilket får forureningen til at drive vestpå mod områder inklusive Hafnir. I denne periode er det også muligt, at vinden til tider kan blive sydøstlig, hvilket potentielt kan forårsage forurening i Njarðvík, Keflavík og Sandgerði. Senest på eftermiddagen i morgen (tirsdag) vil vinden skifte til nordøst med 3-8 m/s, hvilket får gasforureningen til at drive mod sydvest (over Grindavík og Svartsengi) og muligvis samle sig nær udbrudsstederne på grund af svag vind. Gasspredningsprognosen kan findes her .

Ingen ændringer i farevurderingen

Farevurderingen er blevet opdateret og gælder fra kl. 15:00 i dag til den 2. april, med forbehold for væsentlige udviklinger. Der er ingen ændringer i farevurderingen, og risikoen for gasforurening er fortsat høj i alle områder bortset fra Sundhnúksgíga kraterrækken (område 3), hvor den vurderes at være meget høj. Faren i område 4 (Grindavík) er fortsat høj på grund af forkastningsbevægelser, synkehuller over sprækker, lavastrømme og gasforurening.

(Klik på kortet for at se det større)

 

Opdateret 22. marts kl. 17:20 UTC

• Opdateret farevurdering.
  
• Øget risiko på grund af gasudledning. Gasspredningsprognose her
  
• Volcanis aktivitet på udbrudsstedet stabil

 

Vulkanaktiviteten på udbrudsstederne nær Sundhnúkur er fortsat stabil. Der er ringe eller ingen jordskælvsaktivitet i diget eller dets nærhed. Landhævningen i området omkring Svartsengi har været meget lille siden digets indtrængning og det efterfølgende udbrud begyndte den 16. marts. Dette tyder på, at mindre magma ophobes under Svartsengi og i stedet strømmer mere direkte ud af reservoiret gennem de eruptive sprækker. Der kan dog være tegn på, at stigningen er steget i Svartsengi siden da, men det kan ikke bekræftes på nuværende tidspunkt. Målinger i de kommende dage vil kaste mere lys over denne udvikling.

Dagens (fredagens) vejrudsigt inkluderer nord til nordvestlig vind omkring 8-15 m/s, skiftende til en mere nordøstlig retning om aftenen med noget lavere hastigheder, og svagere nordøstlig vind i morgen tidlig. Gasemissioner vil for det meste blive rettet syd for udbrudsstederne mod Grindavík. Gasspredningsprognoser kan findes her .

Øgede farer på grund af gasemissioner

Farevurderingen er blevet opdateret og gælder fra kl. 15.00 i dag fredag ​​den 22. marts til mandag den 25. marts kl. 15. Risikoen på grund af gasudledning vurderes at være højere inden for alle regioner sammenlignet med de foregående dage. Det skyldes den ugunstige vejrudsigt for de næste dage og højere målte værdier af svovldioxid (SO2)-emissioner fra udbrudsstederne og lavafeltet end tidligere. I område 1 og 5 (nordvest for udbrudsstederne) er risikoen for lavastrømme lavere, end den var de seneste tre dage. Denne risiko er faldet, fordi lavastrømmen nord for udbrudsstederne er stabiliseret, og lava flyder nu fortrinsvis mod syd. Lavafeltet forbliver dog farligt, fordi det er dannet for ganske nylig.

(Klik på kortet for at se det større)

 

Opdateret 21. marts kl. 11:40 UTC

• Gennemsnitlig udledningshastighed for 17. – 20. marts er 14,5 m ³ /s   

• Den nye lava dækker nu et areal på 5,58 km ² og har et volumen på 20,9 millioner kubikmeter.

• Ophobning af magma under Svartsengi ser ud til at være stoppet, og i stedet strømmer magma direkte til overfladen og føder udbruddet.  

• Der er målt mindre deformationer i Svartsengi-området og i nærheden af ​​digets indbrud.

 

Den eruptive aktivitet ser ud til at have været relativt stabil de sidste 24 timer. De samme åbninger ser ud til at være aktive, og kratere fortsætter med at bygge sig op omkring åbningerne. Lava strømmer mod syd fra kraterne i en aktiv lavastrøm, både på overfladen og under lavaens størknede overflade.

Oversigt over udbrudsstedet taget på et fly i går morges den 20. marts kl. 9.00. Det viser alle de aktive vulkanske åbninger.

I går morges gennemførte eksperter fra National Land Survey of Iceland og Naturhistorisk Institut luftfotoflyvninger over udbrudsstedet. Ud fra disse billeder er det estimeret, at den gennemsnitlige udledningshastighed for udbruddet i perioden 17.-20. marts er 14,5 m3/s. Dette er den samme udledningshastighed som observeret under udbruddene i Fagradalsfjall 2021-2023. Udledningshastigheden i de første 24 timer af udbruddet var dog væsentligt højere. Arealet af det nye lavafelt blev målt til 5,58 km2 og rumfanget 20,9 millioner kubikmeter. Kortet nedenfor viser omfanget og tykkelsen af ​​den nye lava målt i går morges den 20. marts. Lavaen er 16 m tyk, hvor den er tykkest ved kraterne.

Kort, der viser omfanget af den nyligt udbrudte lava. Violet lag viser den ældre lava, der brød ud i december 2023, januar 2024 og februar 2024.

Der er målt meget lidt deformation i Svartsengi-området og i nærheden af ​​digeformationen. Enhver målt deformation er så lille, at variationen mellem dage er ubetydelig. Der er behov for adskillige flere datapunkter for at udlede, om en stigning fortsætter i området. Det kan dog fastslås, at magma nu strømmer direkte til overfladen og fodrer udbruddet.

Vejrudsigten i dag for området er nord- og nordvestlig vind, 8-15 m/s, gasforurening er spredt mod øst og sydøst og kunne mærkes i Sydisland, for eksempel i Þorlákshöfn og i Vestmannaeyjar. En mere nordlig vind i morgen (fredag), der får gasforurening til at spredes mod syd og sydøst og kunne mærkes i og omkring Grindavík.

 

Opdateret 20. marts kl. 13:45 UTC

 

Eruptivaktiviteten ser ud til at være relativt stabil, og udbrudsåbninger forbliver de samme steder som i går. Lava flyder fra kratrene mod syd, oven på lava, der flød i de første dage af udbruddet. Lidt eller ingen bevægelse er blevet opdaget på lavastrømsfronterne nær South Coast Road og Svartsengi. Seismisk aktivitet siden udbruddet startede lørdag aften har været mindre.

Vejrudsigten er stigende sydøstlig vind i dag, 13-20 m/s om eftermiddagen, men aftager om aftenen. Gasforurening spredes således mod nordvest og kunne påvises i Reykjanesbær og nærliggende områder. Gasfordelingsprognose kan findes her . Den 17. marts blev SO ₂ -gasudledningen fra udbruddet målt op til 50 kg/s, men foreløbige resultater fra nye målinger tyder på, at udledningen af ​​gas er faldet betydeligt siden da.  

Et InSAR-billede offentliggjort i går viste tydelige tegn på jordinflation i Svartsengi fra 17. til 18. marts. GPS-data fra 18. marts tyder på, at inflationen muligvis er faldende. Dette kan skyldes, at magma nu strømmer mod overfladen i Sundhnúkur-kraterrækken og derfor ikke akkumuleres under Svartsengi. Udviklingen af ​​udbruds- og deformationssignalerne i løbet af de næste par dage vil afsløre, om der vil blive opnået en ligevægt mellem magma-tilstrømningen under Svartsengi og lavastrømmen på overfladen i Sundhnúkur-kraterrækken.

Her til morgen foretog eksperter fra National Land Survey of Iceland og Naturhistorisk Institut luftfotoflyvninger over udbrudsstedet. Ud fra disse billeder er det muligt at estimere størrelsen af ​​lavafeltet og den gennemsnitlige lavastrøm fra udbruddet. Der vil blive offentliggjort estimater, så snart dataene er blevet behandlet.

Billedtekst: Oversigt over udbrudsstedet taget på en flyvning i morges. Det viser alle de aktive vulkanske åbninger og flavastrømme fra dem mod syd. I baggrunden til venstre ses Grindavík og til højre er Svartsengi. (Billede: Birgir V. Óskarsson – Naturhistorisk Institut).

 

Opdateret farekort

Det islandske meteorologiske kontor har opdateret sin farevurdering i lyset af de seneste data. Den nye farevurdering træder i kraft i dag onsdag den 20. marts og gælder indtil den 22. marts, medmindre situationen ændrer sig. Zone 3 (Sundhnúkur-kraterrækken), hvor udbruddet stadig er i gang, forbliver uændret, og faren anses for meget høj. Faren i zone 1 (Svartsengi) anses nu for at være betydelig, mens den tidligere blev anset for høj. Faren i zone 4 (Grindavík) er fortsat høj, da risikoen på grund af synkehuller, forkastningsbevægelser og lavastrøm anses for høj. I zone 3 (Sundhnúkur-kraterrækken) vurderes risikoen på grund af gasforurening som meget høj, men i alle andre områder vurderes risikoen for gasforurening nu at være betydelig, hvorimod den tidligere var høj. Denne ændring skyldes lavere gasemissioner fra udbruddet end ved begyndelsen. Faren på grund af gasforurening og aske vurderes også ud fra vejr- og spredningsprognosen for de næste dage, hvilket påvirker spredningen.

(Klik på kortet for at se det større)
Opdateret 19. marts kl. 17:30 UTC

• Udbruddet fortsætter og har været i gang siden 16. marts kl. 20:23 UTC.
• Vulkansk tremor er detekteret og har været relativt stabil de seneste to dage, hvilket indikerer, at udbruddets kraft ikke er aftaget.
• Inflationen fortsætter i Svartsengi, hvilket tyder på, at magma stadig stiger fra dybden ind i magma-reservoiret under Svartsengi såvel som strømmer mod udbrudsstedet.
• Farevurderingskortet, som blev opdateret i går (18. marts) er uændret.

Udbruddet fortsætter og har nu varet i over to et halvt døgn, hvilket er længere end de tidligere tre udbrud, der har fundet sted i området siden december 2023. Udbrudsaktiviteten er de samme steder som i går eftermiddags, på den sydlige del af den vulkanske sprække. Kraterkanter fortsætter med at bygge op, og lavaspringvandet er stadig betydeligt. Lavastrømsfronten, som lå cirka 300 m fra Sydkystvejen i går, ser ikke ud til at have bevæget sig fremad. Lavastrømmen fra kraterne forbliver for det meste mod syd, med aktive lavastrømsfronter på toppen af ​​lavaen, der flød i begyndelsen af ​​udbruddet.

Seismisk aktivitet har været ubetydelig ved digeområdet siden udbruddet startede, men vulkansk rystelse er registreret og har været relativt stabil de seneste to dage, hvilket tyder på, at udbruddets kraft ikke er aftaget.

Da magma forplantede sig fra Svartsengi mod Sundhnúkur-kraterrækken om aftenen den 16. marts, blev der påvist landsynkning i Svartsengi, som da tidligere magmadige blev dannet. GPS-data og satellitbilleder modtaget efter magma-udbredelsen viser, at overfladeinflationen fortsætter i Svartsengi, hvilket tyder på, at magma stadig stiger op fra dybden ind i magma-reservoiret under Svartsengi, samt fodrer udbruddet.

Det skal bemærkes, at der stadig er opnået relativt få datapunkter i den korte tid siden udbruddet begyndte, og at dataene altid er behæftet med usikkerhed. Deformationsdata, som vil være tilgængelige i løbet af de næste par dage, vil give eksperter mulighed for yderligere at estimere ved hjælp af modelberegninger mængden af ​​magma, der strømmer ind under Svartsengi.

InSAR-billede, der viser målt inflation (røde områder) mellem 17. og 18. marts efter udbruddet begyndte. Billedet er baseret på data fra ICEYE-satellitten

Ifølge målinger foretaget i nat er udstrømningen af ​​gas fra udbruddet faldet i forhold til, hvad den var i begyndelsen af ​​udbruddet. Det er dog stadig sandsynligt, at der vil blive opdaget gasforurening, og vejrudsigten indikerer tiltagende sydvestlig vind, omkring 13-20 m/s på udbrudsstedet i dag, men vinden vil aftage i aften. Gasforureningen er således rettet mod nordøst. Se gasfordelingsprognose her .

Farevurderingskortet, der blev opdateret i går, forbliver uændret indtil kl. 15:00 i morgen den 20. marts, med forbehold for ændringer i situationen.

Opdateret 18. marts kl. 18:30 UTC

 

Det islandske meteorologiske kontor har opdateret farevurderingen for at tage højde for de seneste data. Den nye farevurdering træder i kraft i dag mandag den 18. marts og gælder indtil den 20. marts, medmindre situationen ændrer sig. Zone 3 (Sundhnúkur-kraterrækken), hvor vulkanudbruddet stadig er i gang, forbliver uændret, mens fareniveauet forbliver meget højt. Fareniveauet vurderes at forblive højt i zone 1 (Svartsengi) på grund af gasemissioner og lavastrømme. Det samme gælder for Zone 4 (Grindavík), hvor faren på grund af synkehuller over sprækker, fejlbevægelser, lavastrømme og gasudledning anses for høj. Zone 5 er blevet nedgraderet til betydelig risiko (orange), og Zone 7 er nu nedgraderet til en vis risiko.

Årsagen til at vurdere faren som større i zone 1 end i zone 5 er den tættere afstand til den aktive ende af eruptivfissuren. Vejrudsigten og gasspredningsprognosen for de næste par dage vil påvirke vurderingen af ​​gasforurening og aske i farevurderingen.

 

Opdateret 18. marts kl. 16:50 UTC

• Vulkanudbruddets aktivitet har været relativt stabil siden sent i går.
• Der er en meget langsom bevægelse af lavastrømmen mod vejen Suðurstrandarvegur.
• Her til morgen var lavastrømmen cirka 330 meter fra vejen. Marginen er ikke steget væsentligt siden i går aftes.

 

Eruptiv aktivitet har været relativt stabil siden i går eftermiddags. Udbruddet er fokuseret på to steder langs den eruptive sprække, men de nordligste kratere, der var aktive i går, er ikke aktive nu. De mest aktive områder er nær den sydlige ende af eruptiv sprække, der åbnede lørdag aften, med lava, der strømmer fra disse steder sydpå mod vejen Suðurstrandarvegur. Her til morgen var lavastrømmen cirka 330 meter s fra vejen, med en mindre bevægelse af marginen siden i går aftes. Observationer af området i går aftes indikerer, at der ikke er væsentlig aktivitet eller bevægelse af lavastrømmen, der krydsede vejen Grindavíkurvegur få timer efter udbruddet startede.

 

Udstrækningen af ​​den nye lava er estimeret til at være 5,85 kvadratkilometer, baseret på satellitbilleder optaget kl. 14:56 i går, den 17. marts. Se det medfølgende kort. Denne arealvurdering, baseret på satellitdata, indeholder større usikkerhed end beregninger baseret på luftfotos. Hvis vejrforholdene tillader det, vil der senere i dag blive gennemført en luftundersøgelse af udbrudsstedet, hvilket giver mere nøjagtige beregninger af lavaens areal og volumen.

 

Konturerne af lavastrømmen er tegnet fra satellitbilleder fra Iceye. Det første billede blev taget den 17. marts kl. 01:55 (orange farve), hvilket er cirka fem en halv time efter, at udbruddet begyndte. Det andet billede blev taget kl. 14:56 den 17. marts og viser konturerne af lavaen, som den var dengang, vist med rødt. Lilla farver indikerer lavastrømme fra tidligere udbrud.

Vejrudsigten for senere i dag bringer vind fra sydøst og øst med en hastighed på 8-13 m/s på udbrudsstedet, efterfulgt af aftagende vind fra syd og sydvest. Gasudledningen vil derfor drive mod nordvest og vest, med et skift mod nord senere i dag. Der er betydelig usikkerhed om styrken af ​​gasemissioner. Der ventes vind fra sydvest med en hastighed på 10-18 m/s i morgen tidlig, så gasudslippet vil herefter rejse mod nordøst. Det er usandsynligt, at gasudledningen vil nå Region Hovedstaden på grund af hård vind. Gasspredningsprognosen kan overvåges her .

Der er mindre seismisk aktivitet nær udbrudsstedet og på hele Reykjanes-halvøen. Kun en håndfuld små jordskælv er blevet observeret. Risikovurderingen vil blive opdateret senere i dag.

 

Opdateret 17. marts kl. 18:40 UTC

 

Siden kl. 04:00 UTC i dag er udbredelsen af ​​lava aftaget betydeligt. Udbruddet er dog ikke afsluttet, og lava bliver fortsat ekstruderet fra en 0,5 km lang sprække, som bekræftet af webkamera og dronebilleder. En lavafront strækker sig mod vest fra Sundhnúkur-kraterrækken. Denne front oversvømmede Grindavíkurvegur i de tidlige timer søndag morgen omkring kl. 00:30 UTC, hvilket gjorde vejen ufremkommelig.

Lava rejste også sydpå, og den er nu mindre end 250 m fra Suðurstrandarvegur – hovedvejen på den sydlige kyst af Reykjanes-halvøen. Mellem 10:15 og 16:30 UTC i dag bevægede denne lavafront sig med en gennemsnitshastighed på 12 m i timen. Hvis man antager samme bevægelseshastighed, vil det tage fronten yderligere ~20 timer at nå hovedvejen. I tilfælde af at lavaen når vejen, ville der være behov for yderligere 350 m udbredelse, før lavaen kunne komme ud i havet.

Nedenfor er et kort, der viser nedslagsområdet, hvis lavaen skulle nå havet. Dette scenarie og reaktionsplaner relateret til det er blevet drøftet på statusmøder i Meteorologisk Kontor og Civilbeskyttelse i går og i dag.

I tilfælde af at lava interagerer med havvand, ville der være en række vulkanske risici på grund af den pludselige afkøling af lava. I første omgang ville disse farer omfatte lokaliseret tephraaflejring (faste vulkanske partikler) og dannelsen af ​​vulkanske gasser, primært hydrogenchlorid (HCl). Inden for en radius af 0,5 km fra indsejlingen til havet vil der være potentielt dødelige sundhedsfarer. Med stigende afstand falder sværhedsgraden af ​​de vulkanske farer over en radius på 3 km. Ud over denne afstand ville sundhedsfarer på grund af gasforurening være af mindre karakter.

Baseret på udviklingen af ​​udbruddet i dag er vores vurdering, at lavastrømning i havet er et usandsynligt scenarie. Indtil udbruddet slutter, og lavaudbredelsen stopper helt, forbliver det et resultat at overveje med henblik på risikovurdering. Hvis man antager samme bevægelseshastighed (12 m i timen), ville det tage den sydlige lavafront to dage at nå kysten.

 

Opdateret 17. marts kl. 13:00 UTC

Vulkanudbruddet, der begyndte klokken 20:23 i nat, fortsætter, men i løbet af natten faldt intensiteten af ​​udbruddet, og nu er der tre aktive åbninger på udbrudsspalten. Seismisk aktivitet faldt også signifikant natten over, med meget få jordskælv målt efter 3:00, hvilket faldt sammen med et fald i vulkansk rystelse. Denne udvikling minder meget om de tre tidligere udbrud på Sundhnúkur-kraterrækken.

Kort efter midnat flød lava over Grindavík-vejen mod vandfordelingsrøret fra Svartsengi kraftværk. Der har været begrænset fremskridt i denne lavastrømsfront siden i morges, og den er nu omkring 200 meter fra røret. En anden lavastrømsfront løber langs de beskyttende barrierer øst for Grindavík og mod Suðurstrandarvegur-vejen. Reaktionsarbejdere i området overvåger lavaens fremrykningshastighed, som har været langsom og stabil siden i morges.

Udbrudsspalten, som den var kl. 11:00 i dag. Til højre for billedet er bjerget Stóra-Skógafell, og til venstre er bjerget Sýlingarfell. Den mest aktive del af sprækken er øst for Sýlingarfell, med mindre åbninger mod nord.

Dagens vejrudsigt er nordøstlige vinde på 8-13 m/s med periodisk regn, men vinden vil gradvist aftage. Gasudledninger vil hovedsageligt drive mod sydvest fra udbrudsstedet. I morgen ventes der sydøstlig vind på 8-13 m/s med byger, og gasudslippet vil sandsynligvis drive nordvest. Temperaturer varierer generelt fra 1 til 5 grader Celsius nær udbrudsstederne. Der er betydelig usikkerhed om intensiteten af ​​gasudledninger. Se gasspredningsprognosen her .

 

Opdateret 17. marts kl. 01:25 UTC

 

Det islandske Met Office har opdateret farekortet for området. Lavastrømmen fortsætter mod syd og sydøst. Lavafrontens hastighed anslås til 1 km/t.

Hvis udbruddet fortsætter i samme hastighed, skal scenariet med lava, der når havet, overvejes.

Nu, omkring fem timer inde i udbruddet, har aktiviteten været nogenlunde konstant i hele sprækkens længde.

 

Opdateret 16. marts kl. 23:50 UTC

 

Et vulkanudbrud er begyndt mellem bjerget Hagafell og bjerget Stóra Skógfell. Udbruddet begyndte kl. 20:23 UTC den 16. marts, hvor der hurtigt dannedes en 2,9 km lang sprække. Længden og placeringen af ​​sprækken svarer til udbruddet den 8. februar 2024.

Den præ-eruptive advarselsfase var meget kort. Den første advarsel til Department of Civil Protection and Emergency Management var klokken 19:43 UTC, og udbruddets begyndelse blev bekræftet på webkameraer kun 40 minutter senere. Udbruddet er overstrømmende i naturen, så udbrudsfanen består hovedsageligt af damp og gas.

Billede der viser status for udbruddet kl. 21:40. (Foto: DCPEM/Björn Oddsson)

Den islandske kystvagt udførte en helikopterflyvning over udbrudsområdet. Flyvningen havde eksperter fra IMO, Islands Universitet, Department of Civil Protection and Emergency Management. Lava strømmer mod vest fra udbrudsspalten i retning af Grindavíkurvegur (vej) og beskyttelsesbarriererne for Svartsengi-regionen. Derudover flyder en stor lavalap mod sydøst mod beskyttelsesbarriererne for Grindavík.

Kortet viser sprækkeåbningen med rødt. Orange linjer viser lavabarrierer.

Ud fra indledende vurderinger af webkamerabilleder og luftfotos fra helikopterflyvningen menes udbruddet at være det største (i form af magmaudledning) af de tre tidligere sprækkeudbrud fra Sundhnúkur-kraterrækken. Dette skøn gælder for den første time med eruptiv aktivitet.

Klokken 22:10 UTC var den sydlige lavafront kun 200 m fra barriererne på den østlige side af Grindavík og bevægede sig med en hastighed på omkring 1 km i timen. 22:20 UTC var lava 700 til 800 m væk fra Grindavíkurvegur, nordvest for Grindavík, og bevægede sig med en hastighed på cirka 1 km på 1,5 time.

Opdateret 15. marts kl. 14:30 UTC

 

Større usikkerhed end tidligere om tidspunktet for næste digeindbrud og eventuelt udbrud.

GNSS-forskydninger og nylige interferogrammer viser fortsat oppustning af Svartsengi magma-reservoiret – med en tilsvarende hastighed som den, der blev observeret før digehændelsen den 2. marts 2024. Geodætisk modellering ved hjælp af disse datasæt bekræfter, at inflationskilden også er på en lignende placering og dybde som den. observeret under tidligere inflationsepisoder.

Modellerne angiver en genopladningsvolumen på ca. 4 millioner kubikmeter til Svartsengi-reservoiret siden 3. marts.

For digebegivenhederne, der fandt sted mellem 14. januar og 2. marts, blev fejlgrænsen beregnet til at udløse disse digeindbrud og/eller udbrud konsekvent estimeret til omkring 10 millioner kubikmeter. Dette gjorde det muligt at lave langsigtede prognoser baseret på volumentabet fra magma-reservoiret under digebegivenhederne og derefter estimere tidsvinduet, når denne mængde ville være fuldt genopladet, og dermed udløse den næste hændelse.

Den 2. marts vurderes det dog, at et meget mindre volumen gik tabt fra magmareservoiret under denne hændelse (ca. 1,3 mio. m3), hvilket udløste et mindre digeindbrud, der ikke resulterede i et udbrud.

Et større volumen, sammenlignet med den mængde tabt fra Svartsengi reservoiret den 2. marts, er nu blevet genopladet, men der er endnu ikke sket et nyt digeindbrud/udbrud. Dette indikerer en mulig ændring i magma VVS-systemet og større usikkerhed i den nye fejlgrænse, der nu skal nås, og dermed tidspunktet for næste digeindbrud og/eller udbrud.

Når denne nye grænse er nået, er det mest sandsynlige scenarie endnu en digeindtrængning inden for det eksisterende digeområde – mellem Stóra-Skogfell til Grindavík – som måske eller måske ikke kulminerer i et udbrud.

Seismicitet NW for Grindavík ikke et tegn på digeindtrængen der

Vi kan ikke udelukke muligheden for et udbrud inden for et tilstødende område eller vulkansystem f.eks. vest for Mt Þorbjörn eller i Eldvörp, men før dette sker, skal et nyt dige først trænges ind i det tilsvarende område.

Der er på nuværende tidspunkt ikke tegn på digeindbrud indenfor disse områder. En sådan indtrængen i et nyt område forventes at være præget af en stærk jordskælvssekvens og store mængder jorddeformation detekteret på både GNSS-netværket og på interferogrammer – ingen af ​​disse overvågningsdatasæt viser i øjeblikket noget bevis på dette.

Der har været en stigning i seismiciteten (alle jordskælv < M1,5) nordvest for Grindavík. Det er sandsynligt, at den fortsatte oppustning af Svartsengi magma-reservoiret nu udløser små bevægelser på allerede eksisterende forkastninger i dette område, som blev aktiveret under digebegivenheden den 10. november 2023.

Kortet viser seismicitet registreret fra 3. marts til 14. marts. Sorte linjer skitserer Grabens, der blev dannet i digebegivenheder den 10. november 2023 og 14. januar 2024.

 

Opdateret 12. marts kl. 17:00 UTC

• Mængden af ​​magma under Svartsengi fortsætter med at stige, hvilket kan resultere i et nyt digeindbrud og muligvis et udbrud.
• Et udbrud kan forekomme med meget kort varsel, muligvis mindre end 30 minutter.
• Det mest sandsynlige udbrudssted er mellem Stóra-Skógafell og Hagafell.

 

Modelberegninger viser, at magmaakkumuleringen ved Svartsengi fortsætter med en jævn hastighed. I tidligere hændelser er der dannet en magma-indtrængning, når volumenet af akkumuleret magma har nået 8 til 13 millioner kubikmeter. Det samlede akkumulerede volumen har allerede nået denne tærskel. Trykopbygningen fortsætter derfor med at stige i magmakammeret, og sandsynligheden for et nyt digeindtrængen og endda et udbrud i de næste dage øges.

140 jordskælv er blevet opdaget i nærheden af ​​Sundhnúkur-kraterrækken og Grindavík siden fredag. Størstedelen af ​​disse jordskælv har været mindre eller under størrelsesordenen 1,0, mens den største målte hændelse var en M2,8 fredag ​​aften, på omkring 5 km dybde lige SØ for Þorbjörn. Seismisk aktivitet i området er steget en smule de seneste dage i forhold til sidste uge, hvilket muligvis kan kædes sammen med roligere vinde og optimale vejrforhold til jordskælvsdetektering.

IMO har opdateret farevurderingskortet. Fareniveauet forbliver uændret i forhold til det sidste kort. Det nye farevurderingskort trådte i kraft kl. 15.00 i dag, tirsdag den 12. marts og er gyldigt indtil den 19. marts, med forbehold for ændringer i situationen.

‘

(Klik på billedet for at se det større)

Usædvanligt rytmisk mønster af uro, indtil dette punkt.

Som rapporteret i sidste uge afveg adfærden af ​​digeudbredelsen den 2. marts på nogle måder fra de tidligere digedannelser. Forskere vil fortsætte med at indsamle data og konkludere, om hændelsen den 2. marts indikerer mulige ændringer i det usædvanlige rytmiske mønster af uro med magmaophobning ved Svartsengi og gentagne digeindbrud og udbrud.

Disse uroligheder er tidligere blevet sammenlignet med urolighederne i Krafla, der startede i 1975. I løbet af en periode på 10 år skete der 20 magma-indtrængninger, hvoraf 9 kulminerede med et vulkanudbrud (Se billedet nedenfor). I Krafla trængte urolighederne sig altid ind i det samme dige, men i forskellige størrelsesskalaer. Udbruddene fulgte dog ikke et tilsvarende regelmæssigt mønster som hidtil observeret i Sundhnúkar-kraterrækken og har faktisk været usædvanligt rytmiske.

Billedet viser samspillet mellem magma-indtrængninger og jordløft i midten af ​​Krafla-calderaen. Grafen nedenfor viser højden af ​​målepunktet inden for Krafla-calderaen, og grafen ovenfor viser afstanden fra calderaen til digeformationerne.

 

Opdateret 7. marts kl. 17:00 UTC

 

Sandsynlig række af begivenheder i løbet af de næste dage:

 

• Mængden af ​​magma under Svartsengi fortsætter med at stige, hvilket kan resultere i et nyt digeindbrud og muligvis et udbrud.
• Et udbrud kan forekomme med meget kort varsel, muligvis mindre end 30 minutter.
• Det mest sandsynlige udbrudssted er mellem Stóra-Skógafell og Hagafell.

 

Seismisk aktivitet i forbindelse med de vulkanske uroligheder har været faldende siden lørdag, med meget få jordskælv opdaget i de seneste par dage. Imidlertid har ugunstige vejrforhold forstyrret seismisk overvågning ved at dæmpe små begivenheder, så der har sandsynligvis været yderligere mindre jordskælv, som ikke kunne detekteres.

Vejrforholdene i løbet af de næste 24 timer vil sandsynligvis hindre Meteorologisk Kontors jordskælvsovervågningssystem. Prognosen indikerer, at Reykjanes vil opleve kraftig vind fra sydøst ledsaget af regn og begrænset sigtbarhed, især i bjergområder. Nedbøren vil falde tidligt om morgenen, med lejlighedsvise byger, der falder sammen med nedsat sigtbarhed, der forventes i morgen og de følgende dage. Vinden forventes at aftage i løbet af weekenden og kommer fra sydøst eller nordvest søndag.

Inflationen fortsætter ved Svartsengi, og modelberegninger baseret på GNSS-data fra 3. til 6. marts indikerer, at cirka 1,2 millioner kubikmeter magma er blevet sprøjtet ind i magmakammeret i løbet af disse dage. Derfor er der samlet set samlet omkring 10 millioner kubikmeter magma i magmakammeret siden sidste udbrud. Den nuværende situation svarer derfor til, hvad den var før udbruddet den 2. marts.

Opdateret farevurdering

Meteorologisk Kontor har opdateret farevurderingskortet. Fareniveauet forbliver uændret i forhold til det sidste kort. Der er foretaget en ændring af zoneinddelingen; Zone 2 og 3 er slået sammen til én enkelt zone. På baggrund af aktivitetens udvikling er der ikke længere grund til at vurdere risikoen på disse områder særskilt. Det nye farevurderingskort trådte i kraft klokken 15 i dag, torsdag den 7. marts. Denne farevurdering er gyldig indtil den 12. marts, med forbehold for ændringer i situationen.

 

(Klik på kortet for at se det større)

Opdateret 5. marts kl. 14:20 UTC

 

Sandsynlige scenarier i løbet af de næste par dage:

• Mængden af ​​magma i  Svartsengi-reservoiret fortsætter med at stige, hvilket kan resultere i en ny digeudbredelse og/eller vulkanudbrud i de kommende dage.  
• Et vulkanudbrud kan starte med en meget kort advarselstid, endda mindre end 30 minutter.
• Det er mest sandsynligt, at der vil ske et udbrud i området mellem Stóra-Skógfell og Hagafell. 

 

 

 

Seismiciteten over diget har været lav, siden magmaudbredelsen sluttede lørdag (2. marts) aften. Der er lidt mere aktivitet ved bjerget Fagradalsfjall, hvor der er registreret omkring 20 jordskælv i løbet af de sidste 24 timer.

Modelberegninger indikerer et volumentab på omkring -1,3 millioner kubikmeter fra Svartsengi magma reservoir i lørdags – som fodrede en 3 km lang diget intrusion mellem bjerget Stóra-Skógfell og bjerget Hagafell. Volumentabet fra Svartsengi reservoiret var meget lavere end det, der skete under tidligere hændelser, hvor der blev beregnet et volumentab på omkring -10 millioner kubikmeter.

Kontinuerlig landhævning er påvist på GNSS-observationer siden lørdagens magmaudbredelse. Magmatilstrømning under Svartsengi fortsætter således, og modelberegninger tyder på en tilstrømning/akkumuleringshastighed på omkring en halv million kubikmeter pr. dag. I alt er omkring 9,5 millioner kubikmeter magma blevet genopladet til reservoiret under Svartsengi siden udbruddet den 8.-9. februar. 

Derfor fortsætter trykket i magmareservoiret med at bygge op, og der er øget sandsynlighed for endnu en digeudbredelse inden for Sundhnúkur-kraterrækken og/eller et vulkanudbrud i de kommende dage.

 

 

Grafen viser en sammenligning af volumenstigning i Svartsengi reservoiret før digeudbredelse og/eller udbrud. Status for volumenændringen pr. 4. marts er angivet med den røde linje. Denne linje viser også, hvilken indflydelse magmaudbredelsen den 2. marts havde på akkumuleringsprocessen i magmareservoiret under Svartsengi. De viste mængder på denne graf er afledt af modelberegninger baseret på GNSS-data alene. Fælles InSAR-GNSS-modellering af digebegivenheden i lørdags indikerer et volumentab på omkring -1,3 millioner kubikmeter fra Svartsengi-reservoiret, som fodrede digets udbredelse inden for Sundhnúkur-kraterrækken, uden at resultere i et udbrud. Værdier afledt af både GNSS alene og de fælles InSAR-GNSS inversioner er behæftet med usikkerhed.

 

Vejrforholdene kan påvirke IMO’s overvågningssystemer.

 

Det islandske meteorologiske kontor har opdateret farevurderingskortet, som er uændret i forhold til den tidligere farevurdering. Den nye farevurdering er gyldig indtil torsdag den 7. marts, medmindre udviklingen i aktiviteten kræver en revurdering.

 

 

Vejret i de næste par dage vil sandsynligvis påvirke overvågningssystemerne. Udsigten for ugen er sydøstlig og østlig vind, omkring 10-15 m/s. Regnbyger de fleste dage med stigende vindhastigheder og mere rolige vinde imellem byger.

 

 

Opdateret 4. marts kl. 16:00 UTC

 

Sandsynlige scenarier i løbet af de næste par dage:

• Mængden af ​​magma under Svartsengi fortsætter med at stige, hvilket kan resultere i en magmaudbredelse og endda et vulkanudbrud.
• Et vulkanudbrud kan starte med en meget kort advarselstid, endda mindre end 30 minutter.
• Det er mest sandsynligt, at der vil ske et udbrud i området mellem mt. Stóra- Skógfell og mt. Hagafell.

Modelberegninger tyder på, at mængden af ​​magma, der forplantede sig fra Svartsengi til Sundhnúkur-kraterrækken, var omkring 1,3 millioner kubikmeter.

Det var tidligere blevet beregnet, at omkring 0,5 millioner kubikmeter magma akkumuleres under Svartsengi hver dag. I betragtning af dette vil den samlede mængde magma under Svartsengi være omkring 9 millioner kubikmeter ved udgangen af ​​i morgen, tirsdag den 5. marts.

I tidligere begivenheder har magma forplantet sig, når det samlede volumen af ​​magma akkumuleret under Svartsengi når mellem 8-13 millioner kubikmeter. Derfor er der en øget sandsynlighed for ny magmaudbredelse og vulkanudbrud, når disse betingelser er opfyldt.

Det skal dog også bemærkes, at efter gentagne udbrud i mt. Fagradalsfjall var der eksempler på, at magma nåede langsomt til overfladen uden megen seismisk aktivitet. Denne form for udvikling bør også forventes på Sundhnúkur-kraterrækken.

 

Opdateret 3. marts kl. 12:15 UTC

 

Sandsynligt scenarie i løbet af de næste par dage

 

• Magmavolumen under Svartsengi fortsætter med at stige, hvilket kan føre til endnu en magmaudbredelse og endda et vulkanudbrud.
• Et vulkanudbrud kan starte med en meget kort advarselstid, begivenhed mindre end 30 minutter.
• Et vulkanudbrud vil højst sandsynligt forekomme i området mellem mt. Stóra-Skógfell og mt. Hagafell.

 

Det islandske meteorologiske kontor har opdateret farevurderingskortet på grund af faldet i seismisk aktivitet på Reykjanes-halvøen.

I betragtning af udviklingen i aktiviteten siden i går, er fareniveauet blevet sænket i to zoner – Zone 2 og 3. Fareniveauet forbliver uændret i andre områder, så farevurderingen er nu den samme som før gårsdagens begivenhed.

Farevurderingskortet er gyldigt fra kl. 13.00 UTC i dag den 3. marts til kl. 15.00 tirsdag den 5. marts, medmindre udviklingen i aktiviteten kræver en reevaluering.

 

(Klik på kortet for at se det større)

Opdateret 3. marts kl. 11:50 UTC

 

Seismisk aktivitet ved mt. Sýlingarfell skyldtes en magma-indtrængen. Den seismiske aktivitet startede omkring kl. 16:00 UTC i går (2. marts) og aftog støt efter kl. 18:00, og efter kl. 20:00 var den stort set slut.

Data indikerer, at gårsdagens magma-indtrængen er stoppet ved mt. Hagafell. Sandsynligheden for, at magma stiger op i forhold til denne magma-indtrængning er faldet, men området bliver fortsat nøje overvåget for denne mulighed.

Modelberegninger indikerer, at mængden af ​​magma, der forplantede sig ud af Svartsengi i går, var ubetydelig sammenlignet med tidligere magmaudbredelser, som kulminerede med et udbrud.

Derfor kan det antages, at magmaakkumulering under Svartsengi fortsætter som før, og at den mængde magma, der allerede er ophobet, er tilstrækkelig til at udløse endnu en magmaudbredelse. Det kan forventes, at endnu en magma-udbredelse kan forekomme i de næste par dage, og der er fortsat en øget sandsynlighed for et udbrud, som før gårsdagens begivenhed.

Dette afhænger af, hvor hurtigt trykket forårsaget af magmaakkumulering under Svartsengi bygges op for at udløse en anden magmaudbredelse. 

I betragtning af denne udvikling arbejder det islandske meteorologiske kontor på et nyt farevurderingskort, som vil blive opdateret i de kommende timer.

Sandsynlige scenarier i løbet af de næste par dage:

 

• Magmavolumen under Svartsengi fortsætter med at stige, hvilket kan føre til endnu en magmaudbredelse og endda et vulkanudbrud.
• Et vulkanudbrud kan starte med en meget kort advarselstid, begivenhed mindre end 30 minutter.
• Et vulkanudbrud vil højst sandsynligt forekomme i området mellem mt. Stóra-Skógfell og mt. Hagafell.

Grafen viser en sammenligning af volumen af ​​magma akkumuleret under Svartsengi, før den forplanter sig mod Sundhnúkur-kraterrækken. Magmavolumenets status ved 2. marts efter magmaudbredelsen er angivet med rød farve. Beløbet er udledt gennem modelberegninger baseret på GPS-data og med forbehold for usikkerheder. Ændringer kan variere fra dag til dag, fra at være små til mere fremtrædende ændringer. Den lilla linje viser det magmavolumen, der er akkumuleret før den store digebegivenhed under Grindavík dannet den 10. ^november 2023. 

Opdateret 2. marts kl. 19:10 UTC

 

På dette tidspunkt er den seismicitet, der begyndte lige før kl. 16:00 UTC i dag, ophørt. Det anses således for sandsynligt, at magma-indtrængningen er stoppet midlertidigt eller er væsentligt formindsket. Der bliver dog fortsat målt mindre deformationer i området, så det er for tidligt at påstå, at magma-indtrængningen er afsluttet, og at der ikke vil være et udbrud på nuværende tidspunkt. Når der sker magmaindtrængning, kan deformation måles i flere timer efter, at den seismiske aktivitet er stoppet.

Det islandske meteorologiske kontor fortsætter med at overvåge området for at observere, om aktiviteten genoptages i løbet af de næste par timer, eller om magma-indtrængningen er stoppet helt. Det er fortsat muligt, at magma kan stige op til overfladen, som det er blevet observeret i udbrud nær Fagradalsfjall.

 

Opdateret 2. marts kl. 17:30 UTC

• En intens sværm af mikroseismisk aktivitet finder sted øst for Sýlingarfell på Reykjanes-halvøen.
• Seismiciteten indikerer, at magmabevægelser er begyndt, og at et sprækkeudbrud er sandsynligt.
• Seismiciteten begyndte i den sydlige ende af sprækken, der blev dannet den 18. december 2023.

• Fra kl. 17:30 UTC er det tydeligt, at den seismiske aktivitet har bevæget sig sydpå i retning af Hagafell.

• GPS-baserede målinger i realtid viser meget færre tegn på deformation end før tidligere udbrud siden december 2023. Dette kan betyde, at mindre magma er på vej end før de foregående tre udbrud på Sundhnúkur-kraterrækken.
• På nuværende tidspunkt indikerer dybden af ​​seismiciteten ikke, at magma forplanter sig til overfladen.
• Fra 17:30 UTC er det sandsynlige scenarie, at magma-indtrængen ikke nødvendigvis vil føre til et vulkanudbrud. Men mens situationen fortsat er usikker, kan et forestående sprækkeudbrud ikke udelukkes.

Et nyt farevurderingskort fra IMO blev offentliggjort i dag og er gyldigt til i morgen (3. marts 2024) kl. 17:00 UTC

Opdateret 29. februar kl. 12:30 UTC

• Et udbrud kan starte med meget kort advarselstid, endda mindre end 30 minutter.  
• Placeringen af ​​udbrud er højst sandsynligt i området mellem bjerget Stóra-Skógfell og bjerget Hagafell.  
• Farevurderingen tager ikke højde for vejrforhold eller andre faktorer, der kan påvirke risikoen for at være inden for farezonerne.
• Det er muligt, at der sker et digeindbrud, uden at det resulterer i et vulkanudbrud.

 

Modelberegninger tyder på, at der i dag er ophobet omkring 8,5-9 millioner kubikmeter magma under Svartsengi. Inflationstakten har været nogenlunde konstant de seneste dage. I tidligere udviklinger er inflationstakten faldet kort før et udbrud starter.

Ifølge modelberegninger akkumuleres cirka 0,5 millioner kubikmeter magma i Svartsengi-reservoiret hver 24. time.

I betragtning af forstadier til tidligere vulkanudbrud i Sundhnúkar-kraterrækken stiger sandsynligheden for et vulkanudbrud, når volumenet af magma når 8-13 millioner kubikmeter. Hvis magmaophobningen fortsætter med samme hastighed, skulle mængden nå den øvre grænse i næste uge.

Der er fortsat en øget sandsynlighed for et vulkanudbrud i de kommende dage. Det mest sandsynlige scenario er, at en vulkansk sprække åbner sig i området mellem mt. Stóra-Skógfell og Hagafell-bjerget, som kunne forekomme med en meget kort varslingstid.

Grafen viser en sammenligning af volumen af ​​magma akkumuleret under Svartsengi, før den forplanter sig mod Sundhnúkur-kraterrækken. Status for magmavolumenet den 28. ^februar er angivet med rød farve. Beløbet er udledt gennem modelberegninger baseret på GPS-data og med forbehold for usikkerheder. Ændringer kan variere fra dag til dag, fra at være små til mere fremtrædende ændringer. Den lilla linje viser det magmavolumen, der er akkumuleret før den store digebegivenhed under Grindavík dannet den 10. ^november 2023. 

Et nyt farevurderingskort fra IMO blev offentliggjort i dag og forbliver uændret i forhold til det forrige. Farevurderingskortet er gyldigt indtil 5. ^marts , medmindre udviklingen i aktiviteten kræver en revurdering. Sandsynlige scenarier præsenteret tidligere på ugen forbliver også uændrede (se nyheder fra 26. ^februar ).

Bemærk venligst, at selvom IMO på nuværende tidspunkt ikke har øget fareniveauet på uroområdet, kan udviklingen ske meget hurtigt og uden varsel. Folk, der kommer ind i uroområdet, skal huske på dette. IMO’s farevurdering tager ikke højde for vejrforhold eller andre faktorer, der kan påvirke den involverede risiko, når man befinder sig i et farligt område.

 

Opdateret 27. februar kl. 13:00 UTC

• Akkumuleret magma under Svartsengi når samme mængde som før tidligere udbrud.
• Et udbrud kan starte med meget kort advarselstid, endda mindre end 30 minutter.
• Forhøjede fareniveauer i en opdateret farevurdering på grund af forestående udbrud.
• Placeringen af ​​udbrud er højst sandsynligt i området mellem bjerget Stóra-Skógfell og bjerget Hagafell.
• Farevurderingen tager ikke højde for vejrforhold eller andre faktorer, der kan påvirke risikoen for at være inden for farezonerne.
• Det er muligt, at der sker et digeindbrud, uden at det resulterer i et vulkanudbrud

 

Modelberegninger tyder på, at omkring 7,6 millioner m ³ magma er blevet genopladet i Svartsengi-reservoiret. I betragtning af forstadier til tidligere vulkanudbrud i Sundhnúkar-kraterrækken stiger sandsynligheden for et vulkanudbrud, når volumenet af magma når 8 – 13 millioner m ³ . Hvis magmaophobningen fortsætter i samme hastighed, skulle mængden nå den nedre grænse i morgen (27. ^februar ).

Seismisk aktivitet er steget en smule siden sidste weekend og har været mest fremtrædende lige øst for Mt. Sýlingarfell. Placeringen af ​​den seismiske aktivitet er i et område, der anses for at være den østlige spids af magma-reservoiret, som er centreret under Svartsengi-Þórbjörn-området. Den nuværende seismicitet svarer til den, der blev observeret dage før tidligere vulkanudbrud i området.

Derfor har IMO opdateret farevurderingen for uroområdet. Øget sandsynlighed for et vulkanudbrud og relaterede farer påvirker vurderingen. Fareniveauerne er blevet hævet i flere zoner. Selvom farven på Zone 4 – Grindavík – forbliver uændret, er farerne dér øget på grund af muligheden for lavastrømme. Det samme gælder for Zone 1 – Svartsengi.

Ingen væsentlige deformationer i Grindavík er blevet opdaget af GNSS eller satellitdata. Det er dog sandsynligt, at nye fejl vil blive afsløret, når sneen smelter eller nedbør får jord, som kan dække forkastninger, til at blive skyllet væk.

 

 

Sandsynlige scenarier

Hvis der opstår et udbrud, vurderer forskerne, at magma højst sandsynligt vil forplante sig fra reservoiret under Svartsengi-Þórbjörn-regionen mod Sundhnúkur-kraterrækken, hvilket resulterer i lava-springvand og lavastrømme i området mellem Stóra-Skógfell og Hagafell. Det primære signal for stigende magma er en pludselig stigning i seismisk aktivitet med mange lokaliserede jordskælv af lille størrelse. I betragtning af de tidligere vulkanudbrud i området, kan et udbrud starte med meget lidt advarsel (mindre end 30 minutter), afhængigt af hvor magma når overfladen på Sundhnúkur-kraterrækken. 

 

 

På et samfundsmøde afholdt i dag med beboere i Grindavík præsenterede IMO resultater fra lavastrømsmodeller, der viser scenarier, der anses for at være sandsynlige, og som blev forklaret før sidste weekend.

De præsenterede modellerede resultater viste estimeret lavastrøm fra to separate eruptive sprækker placeret på Sundhnúkur-kraterrækken. Lavastrømsmodellerne forudsiger ikke opførselen af ​​det næste vulkanudbrud.  Modellerne bruges kun til at forudsige mulige lavastrømningsbaner fra forskellige placeringer af eruptive sprækker.

Mange faktorer påvirker en lavastrøm: placeringen og længden af ​​den eruptive sprække, volumen af ​​udbrudt materiale, topografi af landoverfladen og om der dannes kratere eller lavalapper.

Disse modellerede scenarier forudsiger lava, der strømmer fra en 800 m lang eruptiv sprække med en konstant ekstruderingshastighed på 600 m 3 /s. Sprækkerne er vist på kortene som sorte streger.

Disse modellerede resultater nedenfor er derfor kun 2 eksempler for Sundhnúkar kraterrækken, men lavastrømmens adfærd i det næste vulkanudbrud kan være meget forskellig afhængig af hvor præcist en sprække åbner på overfladen og hvor lang den vil være. Et mindre skift i placeringen kan ændre lavastrømmens vej betydeligt.

 

 

Udbrud mellem Sýlingarfell og Stóra-Skógfell – Som skete den 18. december 2023 og den 8. februar 2024. 

• Precursor: Pludselig, lokaliseret og intens seismisk aktivitet med små jordskælv. Deformation over magmadiget (hvis et dige er trængt ind) og Svartsengi magmareservoiret 
• Meget kort advarselstid (mindre end 30 minutter), fordi en ny digeudbredelse muligvis ikke er nødvendig for at magma når overfladen. 
• Lava når Grindavík-vejen inden for 2 til 4 timer, men muligvis mindre, hvis hastigheden af ​​den fremrykkende lavafront er højere end den, der er observeret under tidligere udbrud

De præsenterede modellerede resultater viste estimeret lavastrøm fra en sprække lige syd for Stóra-Skógfell. Lavastrømsmodellerne forudsiger ikke opførselen af ​​det næste vulkanudbrud.  Modellerne bruges kun til at forudsige mulige lavastrømningsbaner fra forskellige placeringer af eruptive sprækker. Hastigheden af ​​den fremadskridende lavafront kan også være højere end den, der er vist i modellen.

 

Udbrud af Hagafell – Som sket den 14. januar 2024.

 

• Forløber: Seismisk aktivitet med små jordskælv på Sundhnúkur-kraterrækken, der starter nær Sýlingarfell og migrerer sydpå. Deformation over magmadiget og Svartsengi magmareservoiret
• Sandsynligvis varslingstid er cirka 1-3 timer fra opdagelsen af ​​de første jordskælv til starten af ​​et udbrud.
• Lava når lavabarriererne omkring Grindavík inden for 1 time.
• Magma-indtrængen, som når syd for Hagafell, vil sandsynligvis forårsage betydelige fejlbevægelser i Grindavík

De præsenterede modellerede resultater viste estimeret lavastrøm fra en sprække vest for Hagafell. Lavastrømsmodellerne forudsiger ikke opførselen af ​​det næste vulkanudbrud.  Modellerne bruges kun til at forudsige mulige lavastrømningsbaner fra forskellige placeringer af eruptive sprækker. Hastigheden af ​​den fremadskridende lavafront kan også være højere end den, der er vist i modellen.

 

Udbrud inde i lavabarriererne omkring Grindavík

 

• Seismisk aktivitet med små jordskælv på Sundhnúkur-kraterrækken, der starter nær Sýlingarfell og migrerer sydpå. Deformation over magmadiget og Svartsengi magmareservoiret
• Sandsynlig varslingstid er mellem cirka 1-5 timer fra opdagelsen af ​​de første jordskælv til starten af ​​et udbrud.
• Det er muligt, at en udbrudssprække vil åbne sig inden for Grindavík eller regionen lige nord herfor (inde i barriererne). Lignende aktivitet fandt sted den 14. ^januar , da en vulkansk sprække åbnede sig lige inden for byens ydre omkreds cirka 4 timer efter et udbrud nær Hagafell.
• Magma-indtrængen, som når syd for Grindavík, vil forårsage betydelige fejlbevægelser i Grindavík.

Det islandske meteorologiske kontor og Islands Universitet har samlet materiale, der beskriver den vulkantektoniske reaktivering af Reykjanes-halvøen siden 2019. Se her .

 

Opdateret 23. februar kl. 15:00 UTC

 

Modelberegninger viser, at ca. 5 millioner kubikmeter magma var genopladet til Svartsengi-reservoiret den 22. februar. I betragtning af den tendens, der er observeret før tidligere vulkanudbrud i Sundhnúkur-kraterrækken, er sandsynligheden for et udbrud meget høj, når volumenet når mellem 8-13 millioner kubikmeter (afledt af fælles InSAR-GNSS-modeller). Baseret på resultaterne af modelberegningerne kan dette ske i begyndelsen af ​​næste uge, hvis magmaakkumuleringen fortsætter med den nuværende hastighed.

Det skal bemærkes, at der er en vis usikkerhed i denne fortolkning, og det kan ikke antages, at adfærden vil være identisk med de tidligere udbrud her. Efterhånden som magma VVS-systemet udvikler sig, kan vi heller ikke udelukke muligheden for, at mængden af ​​magma, der kræves for at udløse en ny digebegivenhed og/eller udbrud, kan blive reduceret.

Derudover er der mulighed for, at der sker en ny digeindtrængning i denne region uden at resultere i et vulkanudbrud.

 

 

 

 

 

Figur: Grafen viser en sammenligning af mængden af ​​magma akkumuleret under Svartsengi, før magmaen strømmede mod Sundhnúkur-kraterrækken under de seneste digeindtrængninger og udbrud, der fandt sted mellem december 2023-februar 2024. Volumenet er beregnet ved en model baseret på GNSS data og er behæftet med usikkerhed. Der kan også observeres betydelige variationer mellem på hinanden følgende dage. Den nuværende magma-akkumuleringsstatus pr. 22. februar er markeret med den lilla linje. Den røde linje viser mængden af ​​magma, der er akkumuleret før den store digebegivenhed under Grindavík den 10. november.

 

 

 

Hvis der opstår et udbrud, vurderer forskerne, at magma højst sandsynligt vil forplante sig fra reservoiret under Svartsengi mod Sundhnúkur-kraterrækken, hvilket resulterer i lava-springvand og lavastrømme i området mellem Stóra-Skógfell og Hagafell. Det primære signal for stigende magma er en pludselig stigning i seismisk aktivitet med mange lokaliserede jordskælv af lille størrelse. I betragtning af de tidligere vulkanudbrud i området, kan et udbrud starte med meget lidt advarsel (mindre end 30 minutter), afhængigt af hvor magma når overfladen på Sundhnúkur-kraterrækken.

 

Sandsynlige scenarier

Udbrud mellem Sýlingarfell og Stóra-Skógfell – Som sket den 18. december 2023 og den 8. februar 2024 .

• Precursor: Pludselig, lokaliseret og intens seismisk aktivitet med små jordskælv. Deformation over magmadiget (hvis et dige er trængt ind) og Svartsengi magmareservoiret 
• Meget kort advarselstid (mindre end 30 minutter), fordi en ny digeudbredelse muligvis ikke er nødvendig for at magma når overfladen. 
• Lava når Grindavík vej på mindre end 4 timer.

Udbrud af Hagafell – Som sket den 14. januar 2024.

• Forløber: Seismisk aktivitet med små jordskælv på Sundhnúkur-kraterrækken, der starter nær Sýlingarfell og migrerer sydpå. Deformation over magmadiget og Svartsengi magmareservoiret
• Sandsynligvis varslingstid er cirka 1-3 timer fra opdagelsen af ​​de første jordskælv til starten af ​​et udbrud.
• Lava når lavabarriererne omkring Grindavík inden for 1 time.
• Magma-indtrængen, som når syd for Hagafell, vil sandsynligvis forårsage betydelige fejlbevægelser i Grindavík

Udbrud inde i lavabarriererne omkring Grindavík

• Seismisk aktivitet med små jordskælv på Sundhnúkur-kraterrækken, der starter nær Sýlingarfell og migrerer sydpå. Deformation over magmadiget og Svartsengi magmareservoiret
• Sandsynlig varslingstid er mellem cirka 1-5 timer fra opdagelsen af ​​de første jordskælv til starten af ​​et udbrud.
• Det er muligt, at en udbrudssprække vil åbne sig inden for Grindavík eller regionen lige nord herfor (inde i barriererne). Lignende aktivitet fandt sted den 14. ^januar , da en vulkansk sprække åbnede sig lige inden for byens ydre omkreds cirka 4 timer efter et udbrud nær Hagafell.
• Magma-indtrængen, som når syd for Grindavík, vil forårsage betydelige fejlbevægelser i Grindavík.

 

Selvom der er klare indikationer på stigning i Svartsengi-Þórbjörn-området (relateret til magma-opladning af dette reservoir), betyder dette ikke, at det er det mest sandsynlige sted for et udbrud at starte. Dette skyldes, at magma-reservoiret i øjeblikket svigter på sin nordøstlige kant og føder digeudbredelsen, som påbegyndes mellem Stóra-Skógfell- og Sundhnúkur-kraterrækken. I et scenarie, hvor magma stiger op mod overfladen direkte fra Svartsengi-reservoiret, anslås det, at de første tegn på magma-vandring vil blive opdaget 4-7 timer før magma når overfladen.

Bemærk venligst, at disse scenarier er baseret på fortolkninger af de seneste data og den observerede udvikling af de tidligere hændelser ved Sundhnúkur-kraterrækkeområdet. Der skal tages højde for usikkerhed i denne fortolkning, da den kun er baseret på få begivenheder.

 

 

Opdateret 23. februar kl. 9:30 UTC

 

Seismisk aktivitet i uroområdet nord for Grindavík er fortsat minimal. Omkring 20 små jordskælv er blevet opdaget på 24-timers basis de seneste dage.

Magmaophobningen under Svartsengi fortsætter, og tempoet i ophobningen har været ret stabilt. Dette er en lignende tendens, som er blevet observeret før de tidligere vulkanudbrud.

Arrangementet, der startede i slutningen af ​​oktober 2023 med en inflation ved Svartsengi, fortsætter således. Mens magma-akkumulering fortsætter, forventes endnu et vulkanudbrud i lignende områder som før.

Hvis magmaakkumuleringen fortsætter i det nuværende tempo, vil mængden nå en tærskel, der menes at være nødvendig for at udløse en digeudbredelse og endda et udbrud i næste uge. Mængden af ​​magma akkumuleret under Svartsengi før tidligere udbrud anslås at have været 8-13 millioner m ³ . Nye modelberegninger er i gang for at opnå en bedre forståelse af, hvor meget magma der nu er ophobet.

På nuværende tidspunkt vurderes det ikke at være nødvendigt at hæve fareniveauet i området og dermed forbliver farevurderingen udstedt af IMO uændret.

Farevurderingen vil blive opdateret mandag den 26. ^februar , og skulle udviklingen fortsætte i samme hastighed som nu, vil fareniveauerne i zoner blive hævet, da der vil blive ophobet mere magma, og dermed er der større sandsynlighed for et udbrud.

(Klik på kortet for at se det større)

 

Opdateret 20. februar kl. 11:00 UTC

 

Det islandske meteorologiske kontor har udsendt et opdateret farevurderingskort efter Rigspolitichefens beslutning om at ophæve påbudet om en midlertidig evakuering fra Grindavík, der træder i kraft den 19. februar, og på grund af politikommissærens afgørelse i Suðurnes vedr. ændringer i adgangsbegrænsninger for både enkeltpersoner såvel som forretningsdrift.

Et opdateret farevurderingskort er gyldigt fra den 20. ^februar kl.

I den seneste version af IMO’s farevurderingskort er Zone 7 tilføjet i samråd med Civilbeskyttelse. Nesvegur-vejen ligger inden for zone 7, som i øjeblikket er mere brugt til at få adgang til Svartsengi og Grindavík. Farer til stede i zone 7 er fejlbevægelser og synkehuller. Farvekoden for andre områder forbliver uændret i forhold til tidligere farekort.

Læs her om politikommissærens afgørelse på Suðurnes . (islandsk).

Kortet viser som tidligere vurdering af de aktuelle farer samt farer, der kan opstå med kort varsel. Der er kun foretaget en vurdering for farer inden for de definerede zoner, men der kan også være farer uden for dem.

 

Opdateret 15. februar kl. 16:00 UTC

 

Landhævningen i Svartsengi-området fortsætter med lignende tendenser og hastigheder, som er blevet påvist efter digeudbredelse derfra.

 Modelberegninger baseret på GPS-data tyder på, at magmaophobningen fra slutningen af ​​udbruddet 9. ^februar til i går, 14. ^februar , er omkring 2 millioner m ³ . Det blev anslået, at da udbruddet begyndte den 8. ^februar , forplantede sig omkring 10 millioner m ³ magma fra Svartsengi mod Sundhnúkur kraterrækken. Hvis magmaakkumuleringen fortsætter i samme hastighed, vil der være samlet 10 millioner m ³ i slutningen af ​​februar eller begyndelsen af ​​marts, hvorefter sandsynligheden for digeudbredelse og vulkanudbrud vil stige markant. Disse modelberegninger er baseret på GPS-data, men vil blive opdateret, når nye satellitdata kommer ind.

Seismisk aktivitet i de vestlige dele af mt. Fagradalsfjall fortsætter med omkring 80 små jordskælv i størrelsesordenen 1,5 eller mindre, der er registreret siden den 12. ^februar . Dybden af ​​jordskælvene under den vestlige del af mt. Fagradalsfjall ligger 6-8 km. Området forbliver nøje overvåget, men i øjeblikket viser deformationsdata ikke tegn på magmaakkumulering.

Et opdateret farekort er blevet offentliggjort. Den er gyldig indtil den 22. ^februar , medmindre udviklingen kræver en revurdering. De vigtigste ændringer er, at sandsynligheden for udbrudsåbninger er faldet i alle zoner. Sandsynligheden for synkehuller og forkastningsbevægelser anses stadig for høj i zone 4 (Grindavík). Vær opmærksom på, at farezonerne er aktive, og der kan ske ændringer med kort varsel. Ydermere kan der være farer uden for de angivne farezoner, såsom de forkastninger, der opstod den 10. ^november 2023 vest for Grindavík (se fejl på kortet).

(Klik på kortet for at gøre det større)

 

Opdateret 12. februar kl. 16:00 UTC

 

IMO har opdateret farevurderingen i henhold til udviklingen i den eruptive aktivitet. Der er foretaget ændringer i farevurderingen for nogle farer inden for zoner. 

Den samlede farevurdering for området forbliver uændret i forhold til sidste kort. Der vurderes stadig at være synkehuller og forkastningsbevægelser i område 4 (Grindavík).

(Klik på kortet for at gøre det større)

Farevurderingskortet er gyldigt indtil torsdag den 15. februar, medmindre ændringer i aktiviteten kræver en revurdering.   

 

Opdateret 12. februar kl. 14:30 UTC

 

Inflationen er begyndt igen ved Svartsengi efter at have aftaget efter udbruddet, der startede 8. februar. Inflationshastigheden er omkring 0,5-1,0 cm/dag, hvilket svarer til de hastigheder, der blev opdaget før sidste udbrud. Magma fortsætter således med at akkumulere i magma-reservoiret under Svartsengi. Det er derfor højst sandsynligt, at cyklussen fortsætter om et par uger med endnu en digeudbredelse og et vulkanudbrud.

Tidsserier fra GPS-stationen Svartsengi (SENG) siden 11. ^november 2023 i nord-, øst- og lodret retning (hhv. top-, midt- og bundbilleder). Den nederste tidsserie viser landhævningen i millimeter og gårsdagens datapunkt (11. ^februar ) er vist med en grøn prik. De røde lodrette linjer er tidspunkter for de sidste tre udbrud (18. ^december 2023, 14. ^januar 2024 og 8. ^februar 2024).

Siden middag den 8. februar har den seismiske aktivitet i området nord for Grindavík været mindre, omkring 50 små jordskælv er blevet opdaget, som alle var omkring eller mindre end M1,0. En lille seismisk sværm har været i gang i de vestlige dele af bjerget Fagradalsfjall med omkring 100 jordskælv detekteret, for det meste M1 begivenheder eller mindre. Mindre sværme i Fagradalsfjall-området har forekommet hyppigt de seneste uger, dybden af ​​jordskælvene er på omkring 6-8 km.

 

Opdateret 9. februar kl. 15:30 UTC

 

Der blev ikke observeret nogen udbrudsaktivitet i en droneflyvning over udbrudsstedet udført ved middagstid i dag (9. februar) af Rigspolitichefens Specialenhed. Dette tyder på, at udbruddet er ved at ende. Vulkansk tremor detekteres ikke længere på seismiske sensorer.

IMO har opdateret farevurderingen i henhold til udviklingen i den eruptive aktivitet. Der er foretaget ændringer i farevurderingen for nogle farer inden for zoner. Farer på grund af åbning af vulkanske sprækker er faldet, men farer på grund af gasforurening anses stadig for at være sandsynlige af lavastrømmens front. Farer på grund af lavastrøm er stadig på plads, da lava-lapper kan bryde ud fra lavastrømsfronten. Farer på grund af synkehuller og fejlbevægelser anses stadig for at være høje i Zone 4 (Grindavík).

(Klik på kortet for at se det større)

Farevurderingskortet er gyldigt indtil mandag den 12. februar kl. 15.00, medmindre ændringer i aktiviteten kræver en revurdering.   

 

Opdateret 9. februar kl. 13:00 UTC

 

Vulkansk tremor er faldet betydeligt siden i går (8. februar). Faldet blev opdaget kort efter middag i går sammen med nedsat udbrudsaktivitet på den vulkanske sprække, og aktiviteten blev mere begrænset i separate kratere. Midlertidige stigninger i den vulkanske rystelse blev noteret i går aftes, hvilket faldt sammen med øget vulkansk aktivitet i kraterne. I løbet af natten faldt aktiviteten yderligere og mellem klokken 7 og 8 i morges var to udbrudskratere aktive. I de sidste timer er der ikke observeret lava-springvand på web-kameraer, men aktiviteten i kraterne er muligvis stadig i gang.

Satellitradarbillede taget kl. 14:56 i går viser overfladesænkning på 10 cm i Svartsengi-området, nordvest for mt. Þorbjörn, da magma strømmede derfra mod Sundhnúkur kraterrækken. Modelberegninger baseret på disse data tyder på, at omkring 10 millioner m ³ magma er strømmet fra magma-reservoiret under Svartsengi mod udbrudsstedet ved Sundhnúkur-kraterrækken. 

(Klik på Insar-satellitbilledet for at gøre det større)

Seismisk aktivitet på udbrudsstedet har været mindre i løbet af de seneste 24 timer. Omkring 40 jordskælv er blevet opdaget der, rundt omkring eller mindre end M1.

Volumenvurderinger af den udbrudte lava fra udbruddets start kl. 6:02 til kl. 13:00 i går (8. ^februar ) er omkring 15 millioner m ³ , hvilket svarer til en gennemsnitlig ekstruderingshastighed på 600 m ³ /s i løbet af den første syv timer (data leveret af det islandske naturhistoriske institut og Landmælingar Íslands).

Selvom udbruddet er faldet betydeligt, er det stadig for tidligt at erklære, om det er kommet til en ende. IMO holder 24-timers vagt og holder nøje øje med området. En opdateret farevurdering vil blive offentliggjort senere i dag.

 

Opdateret 8. februar kl. 17:15 UTC

 

Kraften i udbruddet fortsætter med at falde. Den eruptive aktivitet er i øjeblikket på to eller tre steder på den eruptive fissur. Den eksplosive aktivitet, der begyndte mellem klokken 13 og 14, er nu for det meste overstået, men mindre konvektive skyer rejser sig fra nogle dele af sprækken.

Synkront med udbruddets aftagende kraft aftog de deformationssignaler, der blev detekteret ved digeområdet, hvilket indikerer, at magma ikke længere stiger op under lige så meget tryk som før. Kort efter udbruddets begyndelse faldt den seismiske aktivitet betydeligt og har indtil videre været mindre. Omkring 20 små jordskælv er blevet opdaget over diget siden klokken 08.00 i morges.

Kortet viser konturerne af lavastrømmen, som den blev set på et satellitbillede taget kl. 12:31 i dag (torsdag den 8. ^– februar). Satellitbilledet viser, at lava flød længst omkring 4,5 km mod vest fra udbrudsstedet. Til sammenligning er lavastrømningsfeltet, som blev dannet ved udbruddet den 18. december 2023, også vist på kortet. Dagens lavastrømme delvist over lavastrømmen dannet i december 2023.

(Klik på kortet for at gøre det større)

IMO har opdateret farevurderingskortet i betragtning af processen med den eruptive aktivitet. Der er foretaget ændringer i farevurderingen for nogle farer inden for zoner. Disse ændringer har dog ikke indflydelse på den samlede farevurdering for zonerne. Det nye lavastrømsfelt er også blevet tilføjet til kortet. Farevurderingskortet er gyldigt til kl. 19.00 i morgen, fredag ​​den 9. februar 2024, medmindre udviklingen i aktiviteten kræver en revurdering.

 

(Klik på kortet for at gøre det større)

Opdateret 8. februar kl. 14:25 UTC

 

Udbruddets styrke er aftagende. Aktiviteten foregår nu hovedsageligt på 3 steder på den eruptive sprække, som åbnede i morges. Dette er ikke ulig den proces, der blev observeret i udbruddet den 18. december 2023, hvor aktiviteten var begrænset til et par kratere få timer efter udbruddets begyndelse.

En iøjnefaldende, mørk fane rejser sig fra den ene del af den eruptive sprække. Dette skyldes sandsynligvis magma-interaktion med grundvand, hvilket resulterer i en let eksplosiv aktivitet, hvor hvid dampfane blandes med mørk vulkansk fan.

Det ser ud til, at tephra ikke rejser langt fra den eruptive sprække i øjeblikket. Vulkanfanen er spredt mod sydvest.

Foto taget mod nordvest. (Foto: Rigspolitikommissærens specialenhed).

 

Opdateret 8. februar kl. 12:20 UTC

 

Geodætiske data tyder på, at deformationen er aftaget markant i digeområdet. Derfor er sandsynligheden for nye eruptive sprækkeåbninger faldet. 

IMO har modtaget anmeldelser om tephrafald i Grindavík. 

Tephra er skummende og vesikulært materiale, som dannes, når lavasprøjt afkøles hurtigt i luften under lavafontæneaktiviteten. Denne proces fandt sted, da en eruptiv sprække åbnede i morges (8. februar 2024). På grund af tefraernes vesikularitet og lethed kan den transporteres langt inde i vulkanfanen med vind. Den falder i Grindavík nu, 3-5 km fra dannelseskilden på grund af lavafontænernes højde, nordøstlig vindretning, termisk opstrømning fra lavaen og lav lufttemperatur.

Tephra er et synonym for alle luftbårne, faste, eruptive materialer, uanset størrelse og type. Tephra-dannelse er velkendt i Island, såsom i de eksplosive udbrud i Grímsvötn 2011 og 2004, og Eyjafjallajökull 2010. I eksplosive udbrud er lavaen mere fragmenteret i luften og producerer finere kornet tephra, men tephra kan også produceres i effusive udbrud som nu er i gang på Reykjanes-halvøen. I effusive udbrud aflejres størstedelen af ​​tephra tæt på udluftningen og er derfor ikke godt påviselig uden for lavastrømningsfeltet. I maj 2021, da lavaspringvandet var mest aktivt i udbruddet i Fagradalsfjall, faldt store stykker tephra (op til 10 cm i diameter) i omkring 1 km afstand fra udbrudskilden.

Tephra er skarp som glas og bør derfor håndteres forsigtigt. Forrudeviskere bør ikke bruges til at fjerne tephra fra køretøjer, da det vil ridse glasset. Tephra bør hellere blæses eller vaskes af med vand fra vinduer og lignende overflader.

Gasspredning

 

Vejrudsigten for gasspredning fra det vulkanske område er nordøstlig vind, 4-8 m/s i dag (torsdag), således at gas spredes mod sydvest. Aftagende vindhastighed i nat, hvilket kan få gaskoncentrationer til at opbygge sig på vulkanområdet. Østlig og sydøstlig vind, 5-10 m/s efter middag i morgen (fredag), hvilket medfører, at gas spredes mod vest og nordvest, mod Keflavík.

 

Opdateret 8. februar kl. 11:40 UTC

Det islandske Met Office har opdateret farekortet for området. Fareniveauet er steget i alle områder på grund af udbruddet.

Opdateret 8. februar kl. 7:50 UTC

 

Klokken 5:30 i morges startede en intens seismisk aktivitet nordøst for mt. Sýlingarfell. Omkring 30 minutter senere startede et vulkanudbrud på stedet.

Den eruptive sprække blev forlænget både mod nord og syd i løbet af de første minutter.

De første billeder fra den islandske kystvagts overvågningsflyvning tyder på, at udbruddet finder sted på et lignende sted som udbruddet den 18. december 2023. Eruptivspalten er cirka 3 km lang, fra mt. Sundhnúkur i syd og strækker sig mod den østlige del af mt. Stóra-Skógfell. Lava strømmer for det meste mod vest i øjeblikket, og strømningen ser ud til at være lidt mindre end ved starten af ​​det 18. december-udbrud.

 

Lavafontænerne når omkring 50-80 m højde, og vulkanfanen rejser sig omkring 3 km over udbrudsspalten. 

 

Billede fra den islandske kystvagts overvågningsflyvning. Mt. Stóra-Skógfell i forgrunden og lysene ved Svartsengi kraftværket til højre. (Foto: Björn Oddsson).

 

Opdateret 5. februar kl. 16:00 UTC

 

Den igangværende magma-akkumulering under Svartsengi-Þorbjörn-området fortsætter, selvom inflationen er faldet en smule de seneste dage. Lignende processer blev observeret før de tidligere digeindbrud og udbrud nord for Grindavík i januar 2024 og december 2023. Ifølge opdaterede geodætiske modeller baseret på satellit- og GNSS-data, der dækker intervallet fra 16. januar til 5. februar, genoplades mængden af ​​magma til Svartsengi reservoir er nu anslået til omkring 9 mio. m ³ . Fra geodætisk modellering af indtrængen og udbruddet i januar 2024 anslås det, at der strømmede omkring 9 til 13 millioner kubikmeter magma fra Svartsengi magma-reservoiret og brødføde det udbrud, der begyndte nær Hagafell den 14. januar. Derfor har den estimerede mængde magma-genopladning nu nået den nedre grænse for den mængde, der menes at være blevet tappet i januar. Derfor er der en øget sandsynlighed for et nyt magmatisk digeindtrængen og efterfølgende vulkanudbrud i de kommende dage til uger.

Siden i fredags er der målt knap 200 jordskælv i området nord for Grindavík, de fleste omkring eller under størrelsesordenen 1 på 3-4 km dybde. Det største jordskælv fandt sted søndag morgen den 4. februar nær Sundhnúkur og var et M2.2 i en dybde på cirka 6 km.

IMO fortsætter med at overvåge området nøje, og det nuværende farevurderingskort forbliver gyldigt indtil kl. 15.00 den 8. februar, hvis der ikke er ændringer i aktiviteten.

Seneste satellitradarsammenligning, der viser jordoverfladeændringer mellem 23. januar og 4. februar 2024. Rød skygge viser området med maksimal inflation og grå skygge viser område, hvor målinger ikke var mulige på grund af variationer i snedække mellem billederne.

 

Opdateret 1. februar kl. 17:00 UTC

 

Modeller baseret på GPS-data, gennemgået i morges (1. februar) af forskere fra det islandske meteorologiske kontor og Islands Universitet, viser, at der er samlet omkring 6,5 millioner kubikmeter magma under Svartsengi-regionen. Ifølge denne vurdering vil magma snart nå samme volumen som drænet under udbruddet i januar 2024. Derfor kan tidsskalaen for det næste udbrud være inden for to uger eller muligvis dage. Det betyder, at sandsynligheden for et magma-indtrængen og et vulkanudbrud er steget.

Der er ingen absolut sikkerhed for, at varslingstiden forud for næste indbrud eller udbrud vil være den samme som 14. januar, hvilket var cirka fem timers varsel fra jordskælvsværmen begyndte, til udbruddet begyndte lige syd for Hagafell. Varslingsperioden for udbruddet mellem Stóra-Skógfell og Sundhnúkur den 18. december sidste år var omkring 90 minutter, og det udbrud fandt sted cirka midt på den (nu størknede) magma-indtrængning under Sundhnúksgígar-kraterrækken. Med gentagne laterale magma-indtrængninger er det sandsynligt, at vejen for magma-udbredelse til overfladen vil være lettere, hvilket resulterer i mindre seismicitet. Hurtige bevægelser af magma er dog altid ledsaget af øget mikroseismicitet. Vi vurderer, at minimumsvarslingstiden vil være en time før et vulkanudbrud, og at den mest sandsynlige vej vil være langs sprækkerne fra magma-indtrængningen den 10. november sidste år.

Seismisk aktivitet har været den samme i den seneste uge. Næsten 200 jordskælv er blevet målt i området mellem Stóra-Skógfell og syd for Hagafell i de seneste syv dage. De fleste af disse jordskælv var mindre, under 1,0 i styrke i en dybde på 2 til 5 km. Det største jordskælv registrerede en styrke på 1,8, og det var placeret omkring en kilometer syd for Hagafell.

Det islandske meteorologiske kontor har udgivet et opdateret farevurderingskort. De vigtigste ændringer er, at zone 3 (Sýlingarfell – Hagafell) er blevet opgraderet til rød (høj risiko), og zone 2 og 6 er blevet opgraderet til rav (betydelig fare). Grindavík (zone 4) forbliver uændret med et betydeligt fareniveau.

 

Den overordnede vurdering for hver zone er baseret på en samlet vurdering af syv typer farer, der kan forekomme inden for de enkelte zoner. Listen på kortet viser farer inden for de zoner, der er klassificeret som “betydelige”, “høje” eller “meget høje”. Farer vurderet som “høj” eller “meget høj” er fremhævet med fed skrift.

 

 

Det skal bemærkes, at selvom den overordnede farevurdering for Grindavík er den samme som i sidste uge, vurderes lavastrømningsfaren nu som høj. Faren for synkehuller, der åbner sig over sprækker i Grindavík, vurderes stadig som meget høj.

Opdateret 25. januar 17:30 UTC

 

Inflationen fortsætter i Svartsengi. I løbet af de sidste par dage er landet steget med en hastighed på cirka 8 mm om dagen, hvilket er lidt over den registrerede stigningshastighed før udbruddet den 14. januar.

På dette tidspunkt er det udfordrende at fastslå præcis, hvor meget magma, der har ophobet sig under Svartsengi, siden udbruddet sluttede den 16. januar. Mest sandsynligt vil tidsrammen, der kræves for at nå den samme mængde magma som før det sidste udbrud, være i størrelsesordenen uger, ikke dage. Beregningsmodeller er ved at blive forfinet for at opnå en klarere vurdering af status for magmaakkumulering.

Lave niveauer af seismisk aktivitet fortsætter og er for det meste koncentreret omkring Hagafell. Den aktuelle seismiske aktivitet stemmer overens med den, der er observeret i området efter det forrige udbrud.

Det islandske meteorologiske kontor har udgivet et opdateret farevurderingskort. De vigtigste ændringer omfatter en reduktion af det overordnede fareniveau for Grindavík til orange (betydelig fare).

Det skal bemærkes, at selvom det overordnede fareniveau for Grindavík er reduceret med et niveau, er faren forbundet med sprækker fortsat meget høj. Den nuværende fare omtales nu som “nedsynkning i en sprække”, der beskriver den fare, der kan være til stede, hvor sprækker er skjult under ustabile overflader, der kan kollapse og udvikle synkehuller.

Farevurderingen relateret til sprækkeudvikling i Grindavík er faldet. Evalueringer er i gang for at afgøre, om der er fare for, at eksisterende sprækker udvider sig, eller at der dannes nye sprækker. GPS-data har udvist meget lidt bevægelse i Grindavík de seneste par dage, hvilket reducerer den vurderede fare sammenlignet med tidligere. Faren på grund af synkehuller, der ligger over sprækker, anses nu for at være betydelig.

(Klik på billedet for at se det større). Øget fare i området på grund af udbruddet nær Hagafell den 16. januar og landhævning nær Svartsengi. Forholdene inden for og uden for fareområderne kan ændres med lidt advarsel. Risikovurdering er udelukkende fokuseret inden for disse områder, men faren kan strække sig ud over dem. Den overordnede farevurdering for hvert område er baseret på en samlet vurdering af 7 typer af farer, der er til stede eller mulige inden for regionerne. Farven på hvert område afspejler den overordnede fare inden for disse grænser.

 

Opdateret 19. januar 16:30 UTC

 

Der registreres stadig tydelige signaler om en fortsat landhævning under Svartsengi. Det er endnu for tidligt at sige, om hastigheden af ​​landhævningen er steget siden før udbruddet den 14. januar. De første målinger tyder på, at det er tilfældet, men som tidligere skrevet kan målinger svinge fra den ene dag til den anden og en længere tidslinje for måling er nødvendig for at kunne fortolke den langsigtede udvikling af landhævningen.

Seismisk aktivitet fortsætter med at falde i området af magmadiget, og deformationssignaler set på GPS-enheder tyder på en betydelig opbremsning af jordens bevægelse sammenlignet med tidligere dage. Disse oplysninger tyder på, at magma ikke længere strømmer ind i diget, og at udbruddet er afsluttet.

GPS-målinger viser også små deformationer i Grindavík. Der er stadig stor fare for, at jorden kollapser til sprækker i byen, og derfor er det vigtigt at kortlægge nye sprækker og ændringer af kendte estimerede.

Det islandske meteorologiske kontor har opdateret farevurderingen på grund af den vulkanske og seismiske aktivitet. Fareniveauet er blevet reduceret i alle zoner.

En samlet farevurdering for zone 1, Svartsengi, er nu nede på gul (moderat fare).

En samlet farevurdering for zone 4, Grindavík, er nu nede i rødt (høj fare). Bemærk, at farven på zoner repræsenterer den overordnede fare inden for disse zoner. En fare, der vurderes til at være større inden for en zone, er skrevet med fede bogstaver i listen over farer på kortet.

Farevurderingskortet træder i kraft kl. 15:00 i dag, fredag ​​den 19. januar og er gyldigt til torsdag den 25. januar kl. 15:00, medmindre der er væsentlige ændringer.

 

Opdateret 18. januar 15:30 UTC

 

Som rapporteret i nyhederne i går, er der stadig klare tegn på landstigning under Svartsengi, men det er stadig for tidligt at bestemme stigningshastigheden på grund af den seneste vulkanske aktivitet i området. GNSS-målinger evalueres for at give en samlet vurdering af situationen. Det ser dog ud til, at deformationen forbliver magen til den, der blev observeret efter vulkanudbruddet den 18. december.

Omkring 200 jordskælv er blevet registreret nær magmakanalen siden i går, hvor det største måler 1,4 i styrke. Siden midnat er der sket cirka 70 små jordskælv, hvilket er færre end målt dagen før. Vejret har påvirket antallet af jordskælv, der er opdaget i de seneste dage, men antallet af jordskælv ser ud til generelt at være faldet.

Der er fortsat en betydelig risiko i Grindavík på grund af sprækker og potentialet for jordkollaps ind i dem .

Opdateret 17. januar kl. 18:00 UTC

 

 

Magmaophobning fortsætter under Svartsengi. Det er for tidligt at hævde hastigheden af ​​landhævningen kort efter vulkanudbruddet. Eksperter vil fortsat vurdere data fra GNSS-stationer i området for at få en samlet vurdering af situationen. En af målerne, som var placeret nord for Grindavík, gik under lava, men over 20 GNSS-stationer er i området og bliver brugt.

Seismisk aktivitet har været mild over magmakanalen i de sidste 24 timer. Ifølge beregningsmodeller ligger magma lavvandet i den sydlige ende af kanalen, hvor landet ser ud til at være stærkt opbrudt, hvilket gør det lettere for magmaen at nå overfladen. Derfor er der fortsat sandsynlighed for, at nye eruptive sprækker kan åbne sig uden varsel.

Der er stadig fare i Grindavík relateret til sprækker og potentialet for jordkollaps ind i dem. Der er sket betydelige deformationer i forbindelse med graben i den østlige del af byen. Disse bevægelser var for det meste langs de sprækker, der blev dannet den 10. november og allerede var blevet kortlagt.

Gasforurening blev målt i går under arbejde på brønde forbundet til forsyningssystemet i Grindavík. Det islandske meteorologiske kontor overvåger ikke lokal gasforurening i Grindavík. Det skal yderligere undersøges, om gasforureningen er relateret til magmaen, der ligger meget lavt i området. Det skal bemærkes, at farlig gasforurening er blandt de emner, der nævnes i den nuværende farevurdering for Grindavík.

IMO har udsendt et opdateret farevurderingskort. Der er ingen ændringer i den samlede farevurdering for områderne i forhold til tidligere. Kortet træder i kraft klokken 15.00 i dag og gælder til fredag ​​den 19. januar klokken 15.00, medmindre der sker væsentlige udviklinger.

 

Opdateret 16. januar kl. 18:00 UTC

 

Magma fortsætter med at akkumulere under Svartsengi med en hastighed svarende til den, der blev observeret før de sidste to udbrud. Dette var konsensus opnået under et høringsmøde mellem forskere her til morgen. Under udbruddet denne sidste søndag, i lighed med udbruddet den 18. december, strømmede magma mod øst fra akkumuleringsstedet under Svartsengi, hvilket skabte en magmaledning, der strækker sig fra Stóra-Skógfell sydpå under Grindavík. Beregningsmodeller understøtter denne observation og indikerer, at magmaens oprindelse var lidt længere mod vest sammenlignet med det tidligere udbrud, hvilket førte til variationer i de seneste GPS-målinger sammenlignet med dem, der blev registreret den 18. december.

Da der dannes en magmakanal tæt på overfladen, forspændes jordskorpen, hvilket får landet over den centrale del af kanalen til at aftage og danne en graben. Derudover er jorden forhøjet på hver side af den. Beregningsmodeller, der blev gennemgået på høringsmødet, viser, at GNSS-stationen i Svartsengi er placeret i kanten af ​​kanalen, hvor jorden hæver sig i takt med, at ledningen dannes. Nu, to dage efter kanalens dannelse, forventes Svartsengi GNSS-stationen at vise nedsynkning, hvis magmaakkumuleringen er ophørt. Dette er dog ikke observeret, hvilket indikerer, at magmaakkumulering fortsætter som før.

Magmakanalen, der blev genereret i udbruddet, der begyndte i søndags, ligger lidt længere mod øst end kanalen, der strakte sig under Grindavík den 10. november. Data indsamlet og behandlet af Islands Naturhistoriske Institut og National Land Survey of Iceland afslører, at en ny graben har dannet øst for den, der dukkede op den 10. november. Den nydannede graben måler cirka 800-1000 meter i bredden, som vist på kortet nedenfor. Den største nedsynkning i den er cirka 30 cm, men det er værd at bemærke, at regionen stadig oplever nedsynkninger, og dalen udvides gradvist. Til sammenligning havde graben, der udviklede sig i Grindavík den 10. november, en bredde på omkring 2 km, hvor den mest markante indsynkning målte omkring 1,3 meter.

Inde i denne nyligt dannede graben er tidligere kortlagte sprækker, der var synlige på overfladen, udvidet, og yderligere sprækker er opstået. Følgelig er risikoen forbundet med disse sprækker og muligheden for jordkollaps i dem steget i den østlige del af Grindavík sammenlignet med tidligere.

 

Kort, der viser placeringen og bredden af ​​graben dannet den 10. november (“Mörk sigdals 10-11. nóvember”) og den nyeste graben, der for nylig blev dannet mod øst (“Mörk sigdals 14-15. janúar”).

Opdateret 16. januar kl. 11:45 UTC

 

Der er i øjeblikket ingen synlig aktivitet i de eruptive sprækker, med den seneste lava observeret udgået fra den nordlige sprække kort efter kl. 1 i nat. Seismisk aktivitet fortsætter med at falde, hvilket betyder, at området er ved at stabilisere sig. Omkring 200 små jordskælv blev registreret nær magmakanalen siden midnat, hvilket indikerer, at magma stadig migrerer. Den mest seismiske aktivitet er placeret nær Hagafell, tæt på den første eruptive sprække, der åbnede søndag morgen. På dette tidspunkt er det for tidligt at erklære, at udbruddet er forbi.

GPS-sensorer fortsætter med at registrere jorddeformation i og omkring Grindavík, hvilket illustrerer, at magmakanalen under Grindavík stadig forårsager udvidelse i området. Termiske billeder fra en drone i aftes viser, at sprækker, der tidligere er kortlagt sydvest for Grindavík, er blevet betydeligt større. Der er fortsat betydelige farer i området.

 

Opdateret 15. januar kl. 16:40 UTC

 

Baseret på webcam-optagelser er det tydeligt, at lavastrømmen er faldet fra de eruptive sprækker, der åbnede i går. Strømmen fra den sydlige eruptivspalte, som opstod omkring middagstid i går nær byens grænse, ser ud til at være ophørt. Størstedelen af ​​den resterende lavastrøm er nu rettet mod sydvest langs de beskyttende barrierer, og dens bane ser ud til at have stabiliseret sig.

Det er svært at vurdere, hvor længe dette udbrud vil vare. Seismisk aktivitet er faldet, og GPS-målinger indikerer, at deformationshastigheden i området er reduceret. Deformation er dog stadig påvist nær den sydligste del af magmakanalen under Grindavík.

Målinger tyder på, at der har været en forskydning på op til 1,4 meter det seneste døgn, fordelt på talrige sprækker inden for byens grænser. Friske sprækker har udviklet sig, og eksisterende er udvidet. Det er muligt, at yderligere sprækker kan dukke op på overfladen i løbet af de næste par dage.

Som tidligere nævnt er udbrudsstederne ekstremt farlige, og muligheden for, at nye sprækker opstår uden varsel, kan ikke afvises. Dette blev demonstreret af den eruptive sprække, der dukkede op nær grænsen til Grindavík i går, som ikke gav nogen genkendelige advarselsskilte på overvågningsudstyret.

I dag blæser der en mild vind fra nordøst ved udbrudsstederne, men den tager til senere på dagen. Derfor driver gasforureningen mod sydvest mod havet. I morgen vil området opleve vind fra nord, der når 10-18 m/s, hvilket får gassen til at drive sydpå. Se vejrtjenestens vejrudsigt for detaljer om gasspredning.

Det islandske meteorologiske kontor fortsætter med at overvåge området og er i direkte kontakt med civilbeskyttelses- og indsatshold i regionen om begivenhedens forløb.

Forskere mødtes i morges til et konsultationsmøde arrangeret af det islandske meteorologiske kontor. De gennemgik de seneste data relateret til udbruddet.Top of Form

I de kommende dage vil der være løbende målinger og indsamling af yderligere data, efterfulgt af analyser. Disse data bliver blandt andet brugt til at konstruere modeller, der forbedrer forståelsen af ​​de præ-eruptive indikatorer, der førte op til denne begivenhed, og til at evaluere den mest sandsynlige progression af udbruddet. Der foretages også sammenligninger mellem udbruddet den 18. december og udbruddet, der begyndte i går for at øge forståelsen af ​​ændringer i området og for at evaluere de mest sandsynlige scenarier fremover.

Det islandske meteorologiske kontor har udgivet et opdateret farevurderingskort baseret på de seneste data. Det forbliver uændret i forhold til sidste opdatering. Kortet er gyldigt indtil kl. 19.00 onsdag den 17. januar, medmindre der opstår nyt.

 

Kort, der viser lavaens udbredelse baseret på målinger udført af det islandske naturhistoriske institut og Islands Universitets institut for geovidenskab. Der blev gennemført undersøgelser to gange i går. Den mørkelilla form viser udstrækningen af ​​lavaen kl. 13.50 den 14. januar, mens den lyse lilla form viser udstrækningen kl. 16.15, næsten 2,5 timer senere. De eruptive sprækker er markeret med røde linjer, mens barriererne konstrueret for at forhindre lava i at nå Grindavík er repræsenteret af orange stiplede linjer

Kort, der viser tykkelsen af ​​lavastrømmen baseret på målinger kl. 13:50 i går.

Opdateret 14. januar kl. 15:30 UTC

 

 

Udbruddet nær Hagafell-Grindavík har bevaret samme styrke den seneste time eller deromkring.

Seismiske målinger viser, at ved begyndelsen af ​​urolighederne i morges (~2:30 om morgenen), flyttede den magmafyldte digeindtrængning sig først fra den SE-kant af Stóra-Skógfell og fortsatte derefter mod sydvest til den sydlige ende af Grindavík. Klokken 05.30 havde seismiciteten nået den nordlige ende af Grindavík, og både seismicitet og deformationsmålinger indikerer, at diget siden har forplantet sig under Grindavík by. En ny eruptiv sprække åbnede kl. 12:10 i eftermiddags, lige nord for byen. Lavastrømme ekstruderet fra denne sprække er nu kommet ind i byen.

På grund af digets udbredelse blev eksisterende forkastninger og sprækker reaktiveret, og der er sandsynligvis dannet nye sprækker i Grindavík.

 

Gas distribution

Det islandske meteorologiske kontors vejrudsigt for gasfordeling fra udbruddet ved Hagafell indikerer, at retningen er nord og nordøst, med en hastighed på 3-8 m/s, og vejret er tørt og lyst i dag. Det bliver til tider overskyet med mindre snefald sent i aften og i morgen tidlig. Det vil klare op om eftermiddagen i morgen. Forureningen fra udbruddet breder sig mod syd og sydvest.

 

Nyt Hazard Map udgivet

Det islandske meteorologiske kontor har opdateret farevurderingskortet i lyset af fortolkningen af ​​de seneste data.

Risikoen er steget på alle områder. Farevurderingskortet er gyldigt indtil kl. 19.00, mandag den 15. januar, medmindre andet er angivet.

Opdateret 14. januar kl. 8:20

 

Et udbrud startede klokken 7:57 UTC

Sprækkeåbningen er sydøst for Hagafell-bjerget.

Den sydligste del af sprækken er omkring 900 m fra byen Grindavík.

Åbningen er syd for lavastrømsafbøjningsbarrierer, der bygges nord for Grindavík. Lava strømmer nu mod byen.

Et billede taget ombord på kystvagtens fly. Sprækkeåbning kan ses med lysene i Grindavík i det fjerne. Et kort, der viser sprækkeåbningen markeret med en rød linje.

 

Opdateret 14. januar kl. 06:15 UTC

Omkring 03:00 UTC i dag begyndte en intens serie af jordskælv ved Sundhnúksgígar-kraterrækken. 

På tidspunktet for offentliggørelsen er der målt over 200 jordskælv i området, og seismiciteten har bevæget sig mod byen Grindavík. 

Indtil videre er det største registrerede jordskælv på 3,5 i styrke, og det blev målt klokken 04:07 UTC ved Hagafell. 

Både realtids GPS-målinger og borehulstrykaflæsninger (fra HS Orka) viser store ændringer siden begyndelsen af ​​dagens jordskælvsaktivitet. Disse observationer, ud over den igangværende seismicitet, bekræfter, at magma bevæger sig inden for regionen. 

Vores vurdering er, at muligheden for et udbrud er stor, og at det kan ske umiddelbart.

Et kort, der viser den seneste jordskælvsaktivitet.

Opdateret 12. januar kl. 17:45 UTC

 

Det islandske meteorologiske kontor har opdateret farevurderingskortet for Grindavík – Svartsengi-regionen på grund af de igangværende uroligheder på Reykjanes-halvøen. Kortet viser som tidligere en vurdering af eksisterende farer, der kan opstå med lidt advarsel inden for de angivne områder. Bemærk, at vurderingen kun gælder for farer inden for de definerede områder, selvom farer er mulige uden for de vurderede regioners grænser.

Med hensyn til farvekodning er den samlede vurdering for de seks zoner uændret i forhold til det tidligere kort. Der er dog en ændring i farevurderingen forbundet med sprækker i Grindavík (zone 4). Farerne forbundet med pludselig åbning af kortlagte og ukendte sprækker i Grindavík vurderes nu at være højere. Det skal bemærkes, at farerne forbundet med sprækker er begrænset til kendte områder inden for kommunegrænsen.

Med mindre andet er angivet, er kortet gyldigt til tirsdag den 16. januar 2024.

 

Opdateret 9. januar kl. 13:00 UTC

 

Seismisk aktivitet fortsætter med at udvise et mønster, der ligner det de seneste dage. Jordskælvets aktivitet er fortsat relativt lav, primært centreret mellem Hagafell og Stóra Skógfell, hvor centrum af indtrængen er beliggende. Derudover er der igangværende seismisk aktivitet i Fagradalsfjall, som har været ved siden 18. december.

Landhævningen måles stadig i Svartsengi-området, der har vist en relativt stabil tendens siden udbruddet den 18. december . Det medfølgende billede, markeret med røde prikker, der repræsenterer data fra GPS-stationen SENG i Svartsengi, illustrerer denne bane. Den seneste stigningshastighed er ca. 5 mm pr. dag, hvilket resulterer i en aktuel højde, der er ca. 5 cm højere end før digets indbrud på 10. november og 18. december sidste år.

Beregninger fra modeller baseret på deformationsmålinger (GPS og satellitbilleder) indikerer, at mængden af ​​magma akkumuleret i reservoiret under Svartsengi har nået et niveau, der kan sammenlignes med det volumen, der førte til dannelsen af ​​magmakanalen og det efterfølgende udbrud den 18. december sidste år. år. Det tyder på, at der er en øget risiko for et udbrud i de kommende dage.

Det islandske meteorologiske kontor udsendte et opdateret farekort den 5. januar, og det vil blive revurderet den 12. januar.

 

Relative målinger fra GPS-stationen SENG i Svartsengi fra begyndelsen af ​​oktober 2023 til i dag, viser nord-, øst- og lodrette komponenter (top, midt, bund). Den nederste kurve viser landhævningen i millimeter, med dagens måling angivet med en grøn prik.

Opdateret 5. januar kl. 17:40 UTC

 

Et nyt farekort er udstedt af IMO. Kortet afspejler en farebaseret vurdering af Grindavík – Svartsengi-regionen, foretaget den 5. januar 2024. Farevurderingen er baseret på de seneste overvågningsdata, herunder seismisk aktivitet og jorddeformation, samt geodætiske modelleringsresultater. Vurderingen tager også højde for sandsynligheden for vulkanske farer i hver af de seks zoner, som vist på kortet.

I dagens vurdering påvirker hovedændringen Svartsengi-regionen (zone 1), som nu anses for at være på et moderat fareniveau, hvilket afspejler et fald i forhold til den tidligere version af farekortet. Begrundelsen for denne ændring er, at farevurderingen på grund af dannelsen af ​​større overfladebrud er faldet, da der ikke er dannet nye større brud på det seneste. Derudover gør de seneste geofysiske observationer sammen med vores videnskabelige konsensus Sundhnúksgígar til det bedste sted for et udbrud.

I mellemtiden fortsætter IMO med at overvåge området, og eventuelle ændringer vil blive kommunikeret direkte til civilbeskyttelsen via de sædvanlige kommunikationskanaler.

 

Opdateret 5. januar kl. 14:30 UTC

 

Landhævningshastigheden nær Svartsengi fortsætter med at falde. Eksperter samlet på Meteorologisk Kontor her til morgen bekræftede dette gennem en analyse af GPS-data. Som tidligere rapporteret, signalerer dette en stigning i magmatrykket, hvilket øger sandsynligheden for et nyt digeindtrængen og potentielt udbrud. Det kan dog ikke udelukkes, at dette alternativt kan tyde på et fald i magmatilstrømningen.

Cirka 490 jordskælv har fundet sted nær magmakanalen siden tirsdag den 2. januar. Blandt disse havde 14 en styrke på over 1,0, hvoraf det største målte 1,8 nord for Hagafell. Onsdag den 3. januar indtraf et jordskælv med en styrke på 4,3 nær Trölladyngja, kort efterfulgt af et jordskælv med en styrke på 3,5 og adskillige efterskælv; omkring 900 jordskælv er blevet målt i området.

Den seismiske aktivitet nær Trölladyngja den 3. januar fandt sted langs en anerkendt brudlinje, hvor større jordskælv tidligere er sket flere gange. Der er intet, der tyder på, at disse jordskælv er direkte forbundet med magmabevægelser. Ikke desto mindre er de bemærkelsesværdige ændringer i landskabet i forbindelse med vulkansk aktivitet i Fagradalsfjall, landhævningen nær Svartsengi, magmakanalen nær Sundhnúk den 10. november og udbruddet den 18. december blevet målt på tværs af det vestlige Reykjanes og påvirker seismisk aktivitet i hele regionen .

Ifølge deres vurdering konkluderer forskerne, at hvis magma når overfladen, vil det mest sandsynlige sted for et efterfølgende udbrud igen være Sundhnúksgígaröðinni, beliggende mellem Stóra-Skógfell og Hagafell. Det er dog vigtigt at huske, at digeindtrængninger ikke altid kulminerer i et udbrud, hvilket aktiviteten ved Fagradalsfjall og også under Krafla-brandene vidner om. 

 

Opdateret 3. januar kl. 12:30 UTC

Klokken 10:50 opstod et jordskælv med en styrke på 4,5 nær Trölladyngja, kort efterfulgt af et andet jordskælv, der målte 3,9 kl. 10:54, og en række efterskælv. Jordskælvene fandt sted i en dybde på cirka 5 km og blev sandsynligvis udløst som reaktion på stress frigivet fra jordbevægelser andre steder på Reykjanes-halvøen. Disse jordskælv blev almindeligt mærket i den sydvestlige region af Island.

Placeringen af ​​jordskælvene er omkring 20 km NNE for Svartsengi, hvor landstigning på grund af magmaakkumulering er i gang. 

Det medfølgende billede viser placeringen af ​​jordskælvet, der fandt sted kl. 10:50 og dets nedslagsområde.

Opdateret 2. januar kl. 14:00 UTC

 

Hastigheden af ​​jordforskydning ved Svartsengi er faldende. Eksperter samlet på Meteorologisk Kontor her til morgen bekræftede dette gennem en analyse af GPS-data.

Opbremsningen af ​​inflationen er en indikation af, at magmatrykket stiger, hvilket øger chancerne for nye digeindtrængen og også vulkanudbrud. Dette er en lignende ændring i jordforskydning, som blev observeret sidst på dagen den 15. december, som kulminerede med et udbrud tre dage senere. Det er dog svært at sige, om dette mønster vil gentage sig.

De første tegn på et forestående vulkanudbrud er en pludselig stigning i seismisk aktivitet, og sådanne tegn blev observeret kort før udbruddet begyndte den 18. december.

I de seneste dage har den seismiske aktivitet i området været relativt konstant, med omkring 200 jordskælv registreret om dagen. De fleste af jordskælvene måler under størrelsesordenen 1,0, men omkring 30 jordskælv med størrelsesordenen over 1,0 er blevet registreret siden den 29. december, hvor det største er en styrke på 2,1 beliggende i den nordlige del af Grindavík.

Fortsat videnskabelig vurdering indikerer, at hvis der skulle opstå et udbrud, er Sundhnúkur-kraterrækken mellem Stóra-Skógafell og Hagafell det mest sandsynlige sted for et udbrud. Det er dog vigtigt at bemærke, at magmavandring ikke altid resulterer i et udbrud, som demonstreret af aktiviteten ved Fagradalsfjall og i Krafla-brandene.

Farevurderingskortet udstedt af Meteorologisk Kontor den 29. december forbliver uændret og er gyldigt indtil 5. januar.

Seismisk aktivitet bliver fortsat målt vest for Fagradalsfjall, hvor omkring 100 små jordskælv er blevet registreret siden 29. december. Yderligere analyse af overvågningsdataene vil snart blive udført for at få et klarere billede af situationen ved Fagradalsfjall.

 

Opdateret 29. december kl. 15:15 UTC

Jorden fortsætter med at puste op ved Svartsengi. På GPS-stationen Svartsengi (SENG) har landet nu nået en tilsvarende højde som målt lige før udbruddet den 18. december. Hævningshastigheden siden 18. december har været konstant, hvilket er forskellig fra situationen før det sidste udbrud, hvor stigningen aftog i dagene før udbruddet. Det er dog vanskeligt at påstå, at stigningen vil bremse før det næste udbrud, selvom dette har været tilfældet i udbrud på Reykjanes-halvøen i de senere år, og det blev også bemærket under Krafla-brandene. Der er fortsat usikkerhed om, hvor meget magmatryk skal bygges op, før magma begynder at bevæge sig mod overfladen.

Det nuværende løft er ikke ledsaget af så meget seismisk aktivitet som tidligere. Årsagen til dette er, at der blev udløst betydelig stress i området under begivenhederne den 10. november og 18. december. Derfor skal der akkumuleres betydeligt mere magma, før den seismiske aktivitet stiger fra dets nuværende niveau. Før det sidste udbrud var der flere jordskælv over 3 og et over 4. Lignende seismisk aktivitet kan forventes i forbindelse med næste magma-indtrængning.

Efterhånden som magmaakkumulering fortsætter under Svartsengi, øges sandsynligheden for endnu en magmaindtrængning og et udbrud for hver dag, der går. Det er mest sandsynligt, at det næste udbrud vil ske i Sundhnúkur, mellem Stóra-Skógfell og Hagafell. Det er vigtigt at bemærke, at indtrængning af magma ikke altid fører til et udbrud, som det fremgår af aktiviteten ved Fagradalsfjall og i Krafla-brandene.

Det islandske meteorologiske kontor har udgivet et opdateret farekort, baseret på fælles fortolkning af data på et statusmøde afholdt i dag, 29. december. Den samlede vurdering af fareniveauer inden for områderne er uændret i forhold til sidste opdatering. Der er dog foretaget ændringer i listen over potentielle farer inden for område 4, Grindavík, hvor risici på grund af mulig lavastrøm og gasforurening er tilføjet. Ændringerne skyldes øgede chancer for et udbrud nord for Grindavík. Dette farekort vil blive gennemgået den 5. januar 2024.

I mellemtiden fortsætter IMO med at overvåge området, og eventuelle ændringer vil blive kommunikeret direkte til civilbeskyttelsen via de sædvanlige kommunikationskanaler.

Opdateret 27. december kl. 14:20 UTC

Siden 22. december er der registreret omkring 730 jordskælv i nærheden af ​​magma-indtrængningen, hvoraf 40 havde en størrelsesorden over M1. Det største jordskælv i denne periode havde en styrke på 2,1 den 26. december nord for Hagafell. De fleste af jordskælvene sker i en dybde på 4 km. Derudover er der mellem den 22. december og i dag blevet lokaliseret omkring 140 jordskælv på den vestlige side af Fagradalsfjall. Fem af disse jordskælv var over M1 i størrelse, og det samlede dybdeområde var 4 til 7 km.

Jorddeformationen fortsætter i Svartsengi-regionen, og deformationshastigheden svarer nu til før udbruddet den 18. december 2023. Det betyder, at magma fortsætter med at akkumulere under Svartsengi. Derfor er det mere og mere sandsynligt, at endnu en magma-indtrængning vil forekomme, hvilket kan føre til et andet vulkanudbrud. Geodætiske modelleringsresultater indikerer, at over 10 millioner m ³ magma blev hentet fra under Svartsengi for at fodre den indtrængning, der dannede sig den 18. december, som førte til udbruddet. Baseret på den igangværende hævningshastighed vil det tage en til to uger for den samme mængde magma at samle sig igen under Svartsengi. Der er stadig betydelig usikkerhed om, hvornår det opbyggede magmatryk vil være tilstrækkeligt til at udløse den næste magmaindtrængning.

Det skal bemærkes, at den oprindelige magma-indtrængning, som blev dannet den 10. november, strakte sig 15 km fra Kálfafellsheiði i nord til sydvest for Grindavík, lige ud for kysten. Det betyder, at magma forplantede sig i dybden under hele området, inklusive byen Grindavík. Det mest sandsynlige kildeområde for det næste udbrud er dog mellem Stóra-Skógfell og Hagafell. Baseret på indsigt fra udbruddet i december 2023, stiger sandsynligheden for den næste begivenhed dag for dag. 

Farevurderingskortet udstedt den 22. december 2023 forbliver gyldigt. Forudsat en uændret situation udsendes et nyt kort den 29. december.

Tidsserier af kontinuerlige GPS-løsninger fra station Svartsengi (SENG). Grafen viser jordforskydninger i tre komponenter over de seneste 90 dage. Fra bund til top er de: op, øst og nord, alle målt i millimeter. Den blå, lodrette linje viser tidspunktet for magmaindtrængningen den 10. november, og den røde linje vulkanudbruddet den 18. december 2023. Hvert datapunkt repræsenterer en 24-timers løsning, og den lodrette komponent viser tydeligt den igangværende jordhævning ved Svartsengi.

Opdateret 22. december kl. 17:00 UTC

Som annonceret i går er sprækkeudbruddet ved Sundhnúksgígar afsluttet. Dette indikerer et midlertidigt ophør af eruptiv aktivitet. I de sidste 24 timer blev der registreret næsten 90 jordskælv i Grindavík, Sundhnúksgígar og Svartsengi-regionerne. Det største jordskælv var M1,6 vest for Hagafell, lige efter kl. 16:00 UTC i går (21. december). Samlet set er seismicitetsniveauerne lave, men varierende på daglig basis.

Ifølge GPS og satellitbaserede målinger var jordløftning i Svartsengi-regionen tydelig umiddelbart efter udbruddet begyndte om aftenen den 18. december. Indledende målinger viser, at stigningshastigheden er større end før udbruddet fandt sted. Dette betyder, at magma-akkumulering fortsætter uformindsket under Svartsengi. Denne udvikling vil sandsynligvis føre til endnu et digeindbrud og i sidste ende et vulkanudbrud. I tilfælde af et udbrud er den mest sandsynlige kilderegion mellem Stóra-Skógfell og Hagafell.

Kontinuerlige GPS-målinger viser, at hastigheden af ​​den daglige jordhævning ved Svartsengi mellem 10. november, hvor den magmatiske indtrængning dannedes, og 18. december gradvist aftog. Denne proces vil sandsynligvis gentage sig selv, hvilket betyder, at det næste digeindbrud kan begynde med lidt advarsel, når hævningshastigheden falder igen. Derfor stiger sandsynligheden for et udbrud dag for dag.

Efter bekræftelse af slutningen af ​​udbruddet den 18. december har det islandske meteorologiske kontor udsendt en ny farevurdering. Farekortet træder i kraft kl. 16.00 UTC i dag (22. december), og det forbliver gyldigt indtil kl. 18.00 UTC den 29. december. De vigtigste ændringer påvirker zone 2 og 3, hvor fareniveauerne er reduceret fra meget høje (lilla) til høje (røde). Farevurderingen for alle andre zoner er uændret. Navnlig er vurderingen for Grindavík uændret i forhold til det tidligere kort, og fareniveauet er fortsat betydeligt . Vi lægger vægt på, at forholdene kan ændre sig hurtigt, og at vejrforholdene i væsentlig grad kan påvirke følsomheden af ​​vores overvågningsnetværk. Under sådanne forhold kan varslingstiden forkortes betydeligt.

Vejrudsigten for Grindavík den 23. december lyder på nordøst vind 10-15 m/s, periodisk snefald og muligvis drivsne. Temperaturerne bliver lave, mellem 3 og 5°C. Den 24. december vinder fra nord 13-18 m/s med enkelte snebyger, men 10-15 m/s om eftermiddagen med aftagende snebyger. Der kan forventes periodisk drivende sne. Temperaturerne vil ligge fra 0 til 2°C

Det seneste farevurderingskort, offentliggjort den 22. december kl. 16:00 UTC. Det er vigtigt at bemærke, at nye farer kan opstå med lidt advarsel inden for de specificerede områder. Derudover gælder vurderingen kun for de specificerede områder, hvorimod farer kan strække sig eller forekomme ud over de identificerede zoner.

Opdateret 21. december kl. 12:55 UTC

Forskere, der fløj over udbrudsstedet i morges, bekræfter, at ingen udbrudsaktivitet er synlig, og at lavastrømmen fra kraterne ser ud til at være ophørt. Glødende er stadig synligt i lavafeltet, muligvis inden for lukkede kanaler. Dette blev også bekræftet af en Elfu-medarbejder i Sýlingarfell. Aktiviteten ser ud til at være aftaget sent i nat eller meget tidligt i morges. Det er dog stadig muligt, at lava flyder i lukkede kanaler, så det er for tidligt at erklære udbruddet for afsluttet.

Jordskælvsaktiviteten er fortsat med at falde, og i løbet af de sidste 24 timer er der målt cirka 70 mindre jordskælv over magmarørene. Det største jordskælv i går skete klokken 14:27 og målte 1,4 i størrelsesordenen, mens det største siden midnat i nat var på 1,9. Deformationsmålinger ved Svartsengi viser lidt bevægelse, men målinger over de næste par dage vil yderligere afklare situationen dér.

Gasspredning, hovedsageligt på grund af afgasningen af ​​lavafeltet, vil i dag være sydøst og ud til havet. I morgen, med en langsommere nordøstlig vind, vil gassen rejse mod sydvest.

På nuværende tidspunkt er det svært at forudsige fortsættelsen af ​​udbruddet, men forskere ved Meteorologisk Kontor vurderer konstant de seneste data og fortsætter med at overvåge området tæt.

Opdateret 20. december kl. 18:50 UTC

Udbruddet, der begyndte i Sundhnúksgígar-kraterrækken den 18. december, startede med betydelig kraft, og varslingsperioden var kort. Der gik omkring 90 minutter fra de første tegn på seismicitet, til udbruddet begyndte. Udbruddet skete på magma-indtrængen, der dannedes den 10. november. Magmaen stammer højst sandsynligt fra under Svartsengi, hvor landet har rejst sig gentagne gange siden 2020.

I det seneste døgn har den højeste aktivitet i udbruddet holdt sig omkring midten af ​​sprækken, der åbnede den 18. december. Seismisk aktivitet har været relativt stabil, og der har været små ændringer i deformation siden udbruddet begyndte. I betragtning af dette vurderer det islandske meteorologiske kontor (IMO), at sandsynligheden for, at et nyt udbrud dannes uden varsel i nærheden af ​​Grindavík, er faldet. Derfor har IMO udsendt et nyt farevurderingskort, der træder i kraft i morgen, torsdag den 21. december kl. 7:00 UTC. Farevurderingskortet er gyldigt indtil 28. december. Det skal bemærkes, at selvom sandsynligheden for dannelse af ventilationsåbninger inden for område 4 er faldet, anses fareniveauet i dette område ikke desto mindre for at være betydeligt. Selvom aktiviteten er faldet siden udbruddet begyndte, er intensiteten af ​​udbruddet stadig betydelig og kan sammenlignes med udbrud ved Fagradalsfjall. Det har også vist sig, at magmaen kan nå overfladen hurtigt, hvilket giver lidt tid til at udsende advarsler.

På grund af det vulkanudbrud, der begyndte ved Sundhnúksgígar-kraterrækken den 18. december, er der en øget sandsynlighed for yderligere udluftningsåbninger på den oprindelige sprække. Baseret på den pludselige indtræden af ​​udbruddet ved Sundhnúksgígar kan varslingstiden for nye sprækkeåbninger være meget kort.

Opdateret 20. december kl. 17:00 UTC

Kraften fra udbruddet fortsætter med at aftage. Nye billeder af området viser, at i øjeblikket er to kratere i udbrud. Det mest aktive i dag er krateret direkte øst for Sýlingarfell, som er det sydligste af de kratere, der var aktive i går.

Lava fortsætter for det meste med at strømme mod øst fra de vulkanske åbninger, men en lava-tunge er også løbet mod vest, nord for Stóra-Skógfell. Den sydligste kant af lavaen ser ikke ud til at være på vej frem. Satellitbilleder taget i aftes viser, at lavafeltet er omkring 3,7 kvadratkilometer stort.

Vinden vil vende nordvest i nat og i morgen, og forureningen vil blive transporteret mod sydøst og ud i havet. Det islandske meteorologiske kontor udsender regelmæssigt gasforureningsprognoser.

Der er sket et markant fald i jordskælvsaktiviteten, og i løbet af de sidste 24 timer er der målt omkring 80 små rystelser over magmakanalerne. Det største jordskælv var 2,2 i størrelsesordenen klokken 10:55 i går morges, og det største siden midnat er 1,2 i størrelsesordenen.

Opdateret 19. december kl. 18:30 UTC

Udbruddet fortsætter med at svækkes. Nye luftbilleder af området viser, at der nu er tre åbninger, der bryder ud sydøst for Stóra-Skógfell, ned fra de tidligere fem. Lavaen er for det meste strømmet mod øst fra udbrudsstedet, men der er også en lava-tunge, der flyder mod vest fra regionen nord for Stóra-Skógfell.

Siden udbruddet begyndte, er omkring 320 jordskælv blevet målt over magmakanalerne. Det største jordskælv, med en styrke på 4,1, fandt sted klokken 23:25 mandag. Efter midnat faldt den seismiske aktivitet markant, og siden kl. 12.00 i dag er der kun registreret 10 jordskælv i regionen. Efter udbruddet ved Sundhnúksgíga sænkede landet i Svartsengi sig mere end 5 cm. Tidligere havde landet hævet sig der med omkring 35 cm siden dannelsen af ​​magmakanalen den 10. november. Det er for tidligt at afgøre, om magma vil fortsætte med at samle sig under Svartsengi, og om landet vil begynde at rejse sig igen.

Mens udbruddet fortsætter ved Sundhnúksgíga, er der en øget sandsynlighed for, at flere åbninger kan åbne langs den oprindelige sprække såvel som længere mod nord eller syd. Når man ser tilbage på optakten til udbruddet, afslører det, at der var cirka 90 minutter mellem de første indikatorer og starten af ​​udbruddet. Derfor kan varslingstiden for nye udluftningsåbninger ved Sundhnúk være meget kort.

Opdateret 19. december kl. 14:30 UTC

Størrelsen af ​​vulkanudbruddet ved Sundhnúksgígar fortsætter med at falde. Lavastrømmen anslås at være omkring en fjerdedel af, hvad den var ved begyndelsen af ​​udbruddet den 18. december, og en tredjedel af den oprindelige sprække er aktiv. Lavafontænerne er også lavere end ved begyndelsen af ​​udbruddet og når omkring 30 meter på deres højeste. Disse tal er baseret på visuelle skøn fra en rekognosceringsflyvning tidligt den 19. december.

Udbruddets udvikling ligner nylige udbrud ved Fagradalsfjall, hvor sprækkerne begynder at trække sig sammen og danne individuelle udbrudsåbninger. I øjeblikket er der omkring fem udbrudsåbninger spredt langs den oprindelige sprække.

Ifølge oplysninger fra videnskabsmænd, der tog på en anden helikopterflyvning med den islandske kystvagt omkring kl. 04:00 UTC i dag, har den samlede længde af sprækkeudbruddet ikke ændret sig meget fra begyndelsen. Der var ringe aktivitet i den sydlige ende af sprækken nær Hagafell, og størstedelen af ​​lavastrømmen er på vej mod øst mod Fagradalsfjall. To vandløb når vest, begge nord for Stóra-Skógfell.

På tidspunktet for offentliggørelsen driver vulkanfanen fra vest og nordvest. Gasforurening kan være mærkbar i Vestmannaeyjar i dag, men ikke andre steder i befolkede områder. Ifølge vejrudsigten kan der blive opdaget gasforurening i hovedstadsområdet sent i aften eller i morgen tidlig.

Et nyt farevurderingskort er under udarbejdelse, og det vil blive offentliggjort senere i dag.

Amplitudebillede fra en ICEYE-satellit optaget kl. 03:11 i morges (19. december 2023). Foreløbig analyse af dette billede viser den nye eruptive sprække (gul linje) og lavastrøm (farvet område). Bemærk, at dæmningerne bygget omkring Svartsengi er tydeligt synlige.

Opdateret 19. december kl. 3:00

Intensiteten af ​​vulkanudbruddet, der startede for omkring fire timer siden, er aftagende. Dette fremgår af seismiske og GPS-målinger. At aktiviteten allerede er faldende er ikke en indikation af, hvor længe udbruddet vil vare, men derimod at udbruddet er ved at nå en tilstand af ligevægt. Denne udvikling er blevet observeret i begyndelsen af ​​alle udbrud på Reykjanes-halvøen i de senere år.

Den eruptive sprække er omkring 4 km lang, med den nordlige ende lige øst for Stóra-Skógfell og den sydlige ende lige øst for Sundhnúk. Afstanden fra den sydlige ende til kanten af ​​Grindavík er næsten 3 km.

Det islandske meteorologiske kontor fortsætter med at overvåge aktiviteten og er i direkte kontakt med civilbeskyttelses- og indsatsenheder i området. Et møde med videnskabsmænd vil blive afholdt i morgen formiddag for at evaluere udviklingen af ​​udbruddet natten over.

Denne nyhed vil blive opdateret kl. 09:00 den 19. december.

Opdateret 19. december kl. 02:10

Ifølge de seneste luftobservationer og seismicitet udvider udbrudsspalten sig mod syd. På tidspunktet for offentliggørelsen var den sydlige ende af sprækken tæt på Sundhnúkur. 

Udbruddet er placeret på digeindtrængningen, der blev dannet i november. Hastigheden af ​​lavaudledning i løbet af de første to timer af udbruddet menes at være på en skala på hundredvis af kubikmeter i sekundet, med de største lavafontæner i den nordlige ende af sprækkerne. 

Lava spreder sig lateralt fra hver side af de nyligt åbnede sprækker. Fra realtids GPS-målinger har betydelig jorddeformation ledsaget åbningen af ​​udbrudssprækkerne. 

Siden midnat den 19. december er niveauet af seismicitet på udbrudsstedet faldet. Derudover tyder estimater af sprækkeforlængelse på, at udbruddet er faldet i intensitet siden det begyndte kl. 22:17 den 18. december.

Opdateret 18. december kl. 23:00

 

Klokken 22:17 i aften begyndte et vulkanudbrud nord for Grindavík på Reykjanes-halvøen. Udbruddet ligger tæt på Sundhnúkagígar, omkring fire kilometer nordøst for Grindavík, og det kan ses på nærliggende webkameraer. Forud for udbruddet skete et jordskælvsværm, der startede kl. 21.00.

 

En kystvagthelikopter vil snart lette for at bekræfte udbruddets nøjagtige placering og størrelse.

Mere information vil snart være tilgængelig.

Opdateret 16. december kl. 14:00 UTC

På nuværende tidspunkt er det for tidligt at sige, om magmaakkumuleringen ved Svartsengi er stoppet, og inflationen er forbi. Deformationshastigheden er faldet noget de seneste dage, men der er brug for flere data for at fortolke den mulige udvikling af aktiviteten i Svartsengi.

Forskere vil fortsætte med at analysere dataene i de kommende dage. 

Et nyt farekort vil blive frigivet onsdag den 20. december, som vil afspejle fortolkningen af ​​de seneste data.

Opdateret 15. december kl. 13:00 UTC

Generelt fortsætter svag seismicitet i det område, der er påvirket af diget, og er for det meste koncentreret nær Hagafell. Siden tirsdag den 12. december er der målt 460 jordskælv, hvoraf 30 var større end M1,0. Det største jordskælv i denne tid var M2,8 nær Hagafell tirsdag morgen. Data fra GPS-stationer og satellitbilleder viser, at løft som følge af ophobning af magma fortsætter omkring Svartsengi. Mens magma fortsætter med at akkumulere i dette område, er yderligere diger eller et udbrud stadig muligt.

Farekortet offentliggjort den 6. december Islandsk kort her nedenfor fortsætter med at være gyldigt indtil 20. december. Forholdene inden for og uden for de afgrænsede farezoner kan ændre sig med lidt advarsel.

Opdateret 13. december kl. 11:15 UTC

Området omkring Svartsengi fortsætter med at blæse op. Inflationstakten er faldet en del siden fredag, men den er stadig større, end den var før dannelsen af ​​diget, der rejste under Grindavík 10. november.

Mens magma fortsætter med at samle sig omkring Svartsengi, er yderligere diger eller et udbrud stadig muligt.

Hvis der dannes et andet dige, anses det for at være mest sandsynligt, at det vil følge samme vej som diget den 10. november. Det mest sandsynlige sted for et potentielt udbrud under disse forhold vurderes at være nord for Grindavík i retning af Hagafell og området omkring Sundhnúkagígar. 

Seismisk aktivitet fortsætter på samme niveau som de foregående dage. Den er generelt svag og mest i området omkring Hagafell.

Opdateret 6. december kl. 18:00 UTC

Seneste geodætiske modelleringsresultater tyder på, at magmatilstrømningen til diget, der blev dannet den 10. november, sandsynligvis er ophørt. Chancerne for et udbrud langs diget på dette tidspunkt er derfor faldet betydeligt. Magmaakkumulering fortsætter dog under Svartsengi.  

Den igangværende aktivitet ved Svartsengi, som begyndte i oktober, er endnu ikke slut, og et nyt kapitel kan være begyndt med en øget chance for en ny magmaudbredelse og efterfølgende øget sandsynlighed for et udbrud. 

Som tidligere nævnt blev diget under Grindavík fodret med magma, der akkumuleredes under Svartsengi. Det er sandsynligt, at denne sekvens af begivenheder vil gentage sig. Når man ser på det overordnede mønster med gentagen magma-akkumulering, kan det estimeres, at den næste magma-udbredelse fra Svartsengi kan være i mindre skala end den, der tidligere blev dannet den 10. november. En magma-udbredelse kunne vare ved i flere timer eller dage med en øget risiko på grund af seismisk aktivitet og deformation i den periode. 

Tegn på en magma-udbredelse omfatter en pludselig stigning i seismisk aktivitet og hurtige ændringer i jordens deformation. Disse tegn kan observeres på instrumenter flere timer før magmaudbredelsen sandsynligvis vil udgøre en trussel mod Svartsengi eller Grindavík. Hvis der opstår en magma-udbredelse, vil det islandske meteorologiske kontor straks aktivere indsatsplaner for offentlig sikkerhed. 

Efter en magma-udbredelse øges sandsynligheden for et udbrud. Som nævnt ovenfor er det mest sandsynligt, at magma vil forplante sig fra Svartsengi ind i det tidligere dannede dige den 10. november. Det gør det til det mest sandsynlige område for et udbrud. 

Det er ikke muligt at estimere, hvornår den næste magmaudbredelse vil finde sted. Usikkerheden er betydelig, og en magma-udbredelse kan ske i løbet af de næste par dage eller muligvis efter flere måneder. 

Det islandske meteorologiske kontor fortsætter med at overvåge området tæt og fortsætter med at overvåge tegn på magmaudbredelse og andre ændringer, der kan udgøre yderligere fare i området nær Svartsengi og Grindavík.

Sammenligning af Svartsengi og Krafla Brande

I den sidste uge er der registreret cirka 300-500 jordskælv i en 24-timers periode omkring digets indbrud. Det største jordskælv var et M2,7 nær Hagafell fredag ​​aften. Siden midnat i dag er omkring 90 jordskælv blevet detekteret langs diget, alle målte under en M2,0. Størstedelen af ​​den seismiske aktivitet er fortsat koncentreret langs midten af ​​diget i omkring 3-4 km dybde. På grund af nedsynkning i Svartsengi har spændingen i jordskorpen ændret sig. Indtil det tidligere stressniveau er nået, kan det forventes, at mindre seismicitet fortsætter i regionen.

På trods af det seneste fald i seismisk aktivitet i de sidste uger, kan der forventes yderligere uroligheder på Reykjanes-halvøen. Eksempler på lignende uroligheder kan ses i Krafla-brandene, der startede i 1975. Over en 10-årig periode var der 20 magmaudbredelser, hvoraf 9 resulterede i et udbrud (se forklarende billede nedenfor). I Krafla-brandene fodrede alle magma-udbredelsen det samme dige, men de varierede i størrelse. En lignende gentagelse kan også observeres i aktiviteten omkring Fagradalsfjall.

De seneste geodætiske modelleringsresultater indikerer, at mængden af ​​magma, der i øjeblikket er akkumuleret under Svartsengi, er betydeligt mindre end volumen akkumuleret før digets indtrængning den 10. november. Når man ser på magma-akkumuleringen og magma-udbredelsen i Krafla-brandene, er det tydeligt, at den største mængden af ​​magma havde ophobet sig i Krafla-calderaen før det første vulkanudbrud. En mindre mængde magma akkumulerede i calderaen, før den næste magma-udbredelse fandt sted. Det kan estimeres, at en lignende udvikling vil ske i forhold til magmaophobning under Svartsengi, og der skal ophobes en mindre mængde magma, før den udløser den næste magmaudbredelse ind i diget. Det er sandsynligt, at langsomt stigende seismicitet vil blive opdaget, før en ny magmaudbredelse finder sted, hvilket indikerer øget tryk under Svartsengi.

Billedet viser samspillet mellem dannelsen af ​​diger og løft midt i Krafla-krateret. Det nederste billede viser højden af ​​land inden for Krafla-krateret, mens det øverste viser afstanden mellem Krafla-krateret og urolighederne. (Páll Einarsson og Bryndís Brandsdóttir, 2021)

Opdateret 1. december kl. 16:50 UTC

 

Seismiciteten på halvøen fortsætter med at falde. I de sidste par dage har det automatiske jordskælvslokaliseringssystem registreret relativt få jordskælv, for det meste mikrojordskælv under størrelsesordenen 1. Den seneste seismicitet er koncentreret i området mellem Sýlingarfell og Hagafell, hvor diget højst sandsynligt fødes af magma, der ophobes under Svartsengi. Nogle deformationer detekteres stadig på cGPS-stationerne tæt på diget, men signalet tolkes nu hovedsageligt som skorpens reaktion på den igangværende inflation i Svartsengi-området.

Selvom aktiviteten langs diget og dets omegn nu foregår med meget lav intensitet, fortsætter inflationen, som startede i Svartsengi få dage efter digets dannelse, med et nogenlunde stabilt tempo. Nogle cGPS-stationer omkring Svartsengi og Mt. Þorbjörn viser en langsom faldende tendens, men andre stationer viser stadig en konstant tendens, hvilket tyder på, at indstrømningshastigheden af ​​magma i dybden ikke er reduceret væsentligt.

Processen, der begyndte den 25. oktober med en betydelig seismisk sværm og toppede den 10. november med dannelsen af ​​et 15 km langt magmatisk dige, er ikke slut. Med sikkerhed kan det konstateres, at en fase er startet, hvor et lignende hændelsesforløb kan gentage sig med tiden.

På dette stadium er det dog svært at sige, hvornår den næste energiske indtrængen af ​​magma på lavere dybde kan forekomme, og om den vil forekomme i et lignende område eller ej. IMO fortsætter med at opretholde overvågningen af ​​området på et højt niveau.

 

Opdateret 29. november kl. 17:00 UTC

Den seismiske aktivitet er fortsat langsomt faldende i løbet af de sidste to dage. I går blev der målt omkring 340 jordskælv nær magma-indtrængningen i området øst for Sýlingarfell, og siden midnat i dag er der registreret omkring 150 jordskælv. De fleste af jordskælvene har været mindre end 1,0.

Hævningshastigheden nær Svartsengi har været faldende, men den er stadig i gang med en hastighed på omkring 1 cm pr. dag. Størstedelen af ​​forskydningen i regionen tilskrives i øjeblikket tilstrømning under Svartsengi med en mindre del, der strømmer ind i den magmatiske indtrængning. Med andre ord er deformationen målt og modelleret ved Svartsengi nu meget større end den, der ses nær magma-indtrængningen, men alle deformationssignaler aftager langsomt. Observerede tegn på indstrømning i den magmatiske indtrængen er nu begrænset til området øst for Sýlingarfell. På trods af opbremsningen af ​​seismisk aktivitet og deformation anses et udbrud stadig for at være muligt. Hvis der opstår et udbrud, er det sted, der menes at være mest sandsynligt, øst for Sýlingarfell.

Her er en tidslinje for GPS-stationen Svartsengi (SENG). Den viser bevægelser over de sidste 90 dage i nordlige, østlige og lodrette retninger. Den blå linje markerer magma-indtrængningen fra den 10. november til i dag.

Dette billede viser bevægelserne fra stationen siden 10. november og frem til i dag .

Opdateret 27. november kl. 16:30 UTC

Seismisk aktivitet har været relativt stabil de seneste par dage med en daglig rate på omkring 500 jordskælv i området ved det magmatiske dige. Det meste af seismiciteten er fortsat i nærheden af ​​Sýlingarfell og Hagafell. Omkring midnat begyndte en kortvarig seismisk sværm i nærheden af ​​Sýlingarfell og varede i omkring en time. I alt blev der registreret 170 jordskælv i området i 3-5 km dybde. Jordskælvene var næsten alle meget små med én M3.0.

Data fra GPS-stationer og satellitbilleder viser, at stigningen fortsætter i området ved Svartsengi, og deformation er stadig i gang langs og omkring diget. Den forhøjede seismiske aktivitet, der fandt sted omkring midnat, er ikke forbundet med ændringer i den igangværende deformation. Både seismiske data og deformationsdata tyder på, at magma fortsætter med at akkumulere under Svartsengi og strømme ind i den midterste del af diget, som blev dannet den 10. november. Den seismiske sværm, der opstod denne nat, kan tyde på stigende tryk i diget.

I lyset af de tilgængelige data og den nyeste analyse anses et udbrud langs diget stadig for sandsynligt, så længe magmatilstrømningen fortsætter. Det vurderes, at området med størst sandsynlighed for et udbrud ligger i den midterste del af diget mellem Hagafell og Sýlingarfell. Farekortet offentliggjort af IMO den 22. november forbliver gyldigt.

Yderligere geodætisk modellering er blevet udført for at rekonstruere udviklingen af ​​diget, som blev dannet den 10. november. Disse nyeste resultater tyder på, at diget i dybden kunne være bredere end oprindeligt vurderet. Den tid, der er nødvendig for at størkne magmaen, der trængte ind i diget, ville derfor blive anslået til at være i størrelsesordenen et par måneder.

Dette billede viser gennemgåede jordskælv siden 24. november.

Opdateret 24. november kl. 13:30 UTC

I går blev der målt omkring 650 jordskælv nær digets indtrængning nord for Grindavík, og siden midnat i dag er der registreret knap 300 jordskælv. De fleste af jordskælvene er under M1,0, men det største jordskælv i de sidste to dage var M2,7 nær Hagafell. Den seismiske aktivitet fortsætter med at falde.

Data fra GPS-målinger viser, at deformationen fortsætter nær Svartsengi, og der måles stadig deformation omkring digets indtrængning. Der er dog tegn på, at deformationshastigheden er faldet baseret på data fra den seneste uge. Selvom fortolkningen af ​​deformationsdata er kompleks på dette stadium. Det skyldes, at andre processer, såsom forkastningsbevægelser relateret til jordskælv og jordskorpens viskoelastiske reaktion på uroligheder i området, har indflydelse på deformationssignalerne.

I betragtning af den seneste fortolkning af alle data, fortsætter sandsynligheden for et vulkanudbrud på et eller andet sted langs længden af ​​magma-indtrængningen. Det er muligt, at magma kan dukke op i området mellem Hagafell og Sýlingarfell. Men efterhånden som skorpeafslapning fortsætter med at forekomme, og seismiciteten falder, sammen med et fald i magmatilstrømningen til indtrængningen, mindskes sandsynligheden for et forestående vulkanudbrud med tiden.

Oversigt over seismisk aktivitet fra fredag ​​den 17. november. Den øverste graf viser antallet af jordskælv i timen, og den nederste graf viser antallet af jordskælv pr. dag. Virkningerne af stærk vind og kraftige havdønninger på Reykjanes-halvøen den 21. og 22. november er tydelige i færre registrerede jordskælv på grund af reduceret følsomhed af det seismiske netværk i det tidsrum.

Opdateret 23. november kl. 12:30 UTC

Den 21. november blev der detekteret omkring 300 jordskælv i området for magma-indtrængningen. Fra midnat den 22. november til kl. 18.00 UTC samme dag var der registreret omkring 100 jordskælv i samme region, hvilket er betydeligt færre end de seneste dage. Derudover er intensiteten af ​​jordskælv over størrelsesordenen 2,0 faldet. I perioden med hårdt vejr den 21. og 22. november blev der arbejdet på at vurdere, hvordan vejrforhold og havdønninger påvirker IMO’s overvågningssystemer.

Magma-tilstrømningshastigheder og skorpejusteringer relateret til dannelsen af ​​indtrængen fortsætter med at falde. Derudover fortsætter jordskorpeløftet nær Svartsengi i et lignende tempo. Geodetiske modeller baseret på data fra 21. november tyder på, at tilstrømningen til intrusionen er størst nær Sundhnúkur-kraterrækken, omkring 4 km nordøst for Grindavík. Mindre overfladeforskydninger er påvist inden for graben-regionen i og omkring Grindavík.

Sandsynligheden for et vulkanudbrud på et eller andet sted langs længden af ​​magma-indtrængningen består. Det er muligt, at magma kan dukke op i området mellem Hagafell og Sýlingarfell. Men efterhånden som skorpeafslapning fortsætter med at forekomme, og seismiciteten falder, sammen med et fald i magmatilstrømningen til indtrængningen, mindskes sandsynligheden for et forestående vulkanudbrud med tiden.

Baseret på de seneste data og i betragtning af aktivitetsudviklingen siden 10. november er sandsynligheden for et pludseligt udbrud i Grindavík byområde dagligt faldende, og den vurderes i øjeblikket som lav. Det kan antages, at nyligt anbragt magma under Grindavík er størknet delvist, hvilket reducerer sandsynligheden for, at magmaen når overfladen inden for bygrænsen. Vi understreger dog, at muligheden for et vulkanudbrud på et tidspunkt i længden af ​​intrusionen, især mellem Hagafell og Sýlingarfell, forbliver plausibel.

Det er tydeligt, at der er en stærk sammenhæng mellem jordskorpehævningen i Svartsengi-regionen og den pludselige, indledende udbredelse af magma-indtrængningen den 10. november. Modeller indikerer, at magmaen i reservoiret under Svartsengi kan være strømmet østpå mod Sundhnúkur-kraterne og efterfølgende dannet den 15 km lange vulkanske indtrængen. Mens skorpeløftningen i Svartsengi fortsætter, forventes det, at den akkumulerende magma igen kan strømme mod øst, hvilket potentielt genaktiverer indtrængningen. Det er også muligt, at der kan dannes en magma-indtrængning vest for magmakroppen, der akkumuleres under Svartsengi. Forgængere til en sådan hændelse vil omfatte udtalt seismicitet og hurtige jordforskydninger, som begge overvåges nøje af IMO kontinuerligt.

Opdateret 21. november kl. 15:30 UTC

 

Siden midnat i dag er der registreret 165 jordskælv på grund af de igangværende vulkanske uroligheder, alle under størrelsesordenen 2,0 i størrelse. Niveauet af seismicitet i dag er betydeligt lavere end i de seneste dage, hvor der blev registreret 1.500-1.800 jordskælv hver dag. Det kan forventes, at det intense vejr, der påvirker landet, har betydning for følsomheden af ​​det seismiske overvågningssystem til at detektere de mindste jordskælv, hvilket gør det svært at vurdere, om den seismiske aktivitet generelt er faldende.

Deformationen i forbindelse med magma-indtrængningen, der blev dannet den 10. november, fortsætter. Ligeledes fortsætter jordskorpehævningen nær Svartsengi. Hastigheden af ​​hævningen ved Svartsengi har været næsten den samme i løbet af det seneste døgn.

I samarbejde med specialister fra Islands Universitet fortsætter IMO med at overvåge området så effektivt som muligt, idet de konstant revurderer og fortolker de modtagne data.

Som tidligere nævnt har IMO øget overvågningen i og omkring Grindavík og området omkring Hagafell. Effektiviteten af ​​denne overvågning afhænger af jordskælvets høje følsomhed og GPS-målinger i realtid, som er meget afhængige af vejrforholdene. Givet vejrudsigten for de næste to dage, som indikerer nedbør og betydelig vind, kan det forventes, at både seismisk overvågning og realtids GPS-observationer vil blive påvirket. Havets bølger skaber også mikroseismer, der overvælder lavfrekvente detektionskapaciteter af seismometre på Reykjanes-halvøen. Tåge og haglbyger kan også påvirke den visuelle bekræftelse af et udbrud, hvilket øger overvågnings- og vurderingsusikkerheden.

 

Opdateret 20. november kl. 13:20 UTC

Siden midnat i dag er over 700 jordskælv blevet opdaget i området for magma-indtrængningen, hvoraf det største var 2,7 på Richterstyrken nær Hagafell. 

I de seneste dage er der målt mellem 1.500 og 1.800 daglige jordskælv i regionen, hvor den største hændelse registrerede en styrke på 3,0 sidste fredag ​​(17. november). Baseret på radarbilleder fra 18. og 19. november 2023 viser det seneste interferogram af magma-indtrængningen og det omkringliggende område en betydelig jordskorpeløft i nærheden af ​​Svartsengi. Det nyligt behandlede interferogram blev gennemgået af eksperter i weekenden (18. – 19. november) fra det islandske meteorologiske kontor, Islands Universitet og Department of Civil Protection and Emergency Management. Resultaterne blev også diskuteret på dagens statusmøde, afholdt i IMO. Den hurtige, igangværende løft tæt på Svartsengi sker i det samme område, hvor stigningen blev målt før magma-indtrængningen dannede den 10. november. Geodætiske modeller udledt af satellitbilleder viser, at løftningen i Svartsengi-området er betydeligt hurtigere end tidligere. Generelt, når der dannes en magma-indtrængning, sker nedsynkning over indtrængningens midterlinje, som det ses i Grindavík, med tegn på landhævning, der kan ses ved siden af ​​indtrængningen. Skorpeløftning i Svartsengi-regionen på grund af magma, der akkumuleres i dybden, har været målbar, siden indtrængen begyndte at dannes den 10. november. Oprindeligt var opløftningstegnet påvirket af dannelsen af ​​indtrængen, men nu er dominansen af ​​dyb magma-genopladning tydelig.

Det klare tegn på jordskorpeløft i Svartsengi-regionen ændrer ikke på sandsynligheden for et udbrud fra magma-indtrængningen. Dette vurderes blandt andet ud fra, at jordskorpen over magma-indtrængningen er meget svagere end skorpen over hævningsområdet tæt på Svartsengi. Så længe der ikke er signifikant seismicitet i Svartsengi-regionen, er der ikke stor sandsynlighed for et udbrud på det sted. Desuden vurderes et udbrud stadig mere sandsynligt fra indtrængningen, især hvis der er en pludselig, stor indstrømning af magma ind i indtrængningen.

Vores overvågnings- og farevurderingsforberedelser er stadig baseret på den antagelse, at situationen kan ændre sig pludseligt med lidt advarsel. Det islandske meteorologiske kontor vil i tæt samarbejde med eksperter fra Islands Universitet fortsætte med at overvåge området tæt med det mål løbende at fortolke og evaluere alle tilgængelige overvågningsobservationer.

COSMO-Skymed interferogram spænder over 24 timer mellem 18-19 november kl. 06:41. Det brede opløftningssignal, der er synligt i orange/rødt omkring Svartsengi, er tegn på, at en dyb oppustning (>5 km) finder sted.

Opdateret 18. november kl. 15:00 UTC

Seismicitet relateret til magma-indtrængen, der pludselig blev dannet for en uge siden, forbliver høj og konstant. Cirka 1.700 jordskælv er blevet registreret i de sidste 24 timer, 1.000 af dem er registreret siden midnat. Det største jordskælv i løbet af de sidste 24 timer havde en styrke på 2,8 og fandt sted nær Hagafell, 3,5 km NNE for Grindavík.

Opdateret 17. november kl. 12:00 UTC

Seismiciteten relateret til magma-indtrængningen, der pludselig blev dannet for en uge siden, forbliver høj og konstant, selvom aktivitetsniveauet er væsentligt lavere end 10. – 12. november 2023. Der er registreret ca. 2.000 jordskælv inden for de sidste 24 timer, med mest aktivitet i et område nord for Hagafell, mod Sundhnúkar-kraterne. Det meste af seismiciteten er mikrojordskælvsaktivitet omfattende jordskælv under M 1. Det største jordskælv i løbet af de sidste 24 timer fandt sted kl. 06:35 nær Hagefell; den havde en størrelsesorden på 3,0.

Ifølge GPS-målinger fortsætter jorddeformationen, men med en faldende hastighed. De seneste geofysiske modeller baseret på GPS-data og satellitbilleder indikerer, at de største bevægelser i magma-indtrængningen finder sted nord for Grindavík, nær Hagafell. Hvis det lykkes magma at nå overfladen, menes Hagafell at være det bedste sted for et udbrud.

Indsynkning over magma-indtrængningen forbliver aktiv, selvom målinger viser en lille opbremsning fra dag til dag. På nuværende tidspunkt viser GPS-stationer placeret i og omkring Grindavík, nær midten af ​​indsynkningszonen, omkring 3-4 cm indsynkning om dagen.

Baseret på fortolkningen af ​​de seneste data og modelresultater er et vulkanudbrud fortsat sandsynligt, med den største sandsynlighed for, at det starter nord for Grindavík nær Hagafell.

Et kort, der viser omfanget af nedsynkningen over magma-instruktionen i og omkring Grindavík. En GPS-station (GRIC) placeret nær midten af ​​synket har registreret et samlet synkning på 25 cm siden begyndelsen af ​​hændelsen.

 

Opdateret 16. november kl. 17:50 UTC

I løbet af de sidste par dage har seismiciteten nær magma-indtrængningen været relativt stabil. Fra kl. 17.00 i dag er der registreret omkring 1.400 jordskælv siden midnat, hvoraf det største er 2,9 i styrke, opstået nær Hagafell lige efter kl. 13.00. De fleste af jordskælvene var under styrke 2, med den højeste koncentration af aktivitet nær Hagafell.

Deformation relateret til magma-indtrængningen bliver fortsat målt, selvom den er aftaget lidt siden i går. De seneste modeller, afledt af GPS-målinger og satellitdata, tyder stadig på, at de største bevægelser af magma-indtrængningen er nord for Grindavík nær Hagafell. Hvis magma formår at bryde igennem til overfladen, er det højst sandsynligt, at det sker i Hagafell-regionen.

Tidligt i dag blev svovldioxid (SO ₂ ), en type vulkansk gas, målt fra et borehul ved Svartsengi, der ligger lige nord for Þorbjörn. Boringen strækker sig mod øst til betydelig dybde mod Sundhnúkur-kraterrækken. Grunden af ​​borehullet når derfor tæt på det sted i skorpen, hvor magma-indtrængningen er lokaliseret. Yderligere gasmålinger vil blive gennemført i morgen den 17. november. Detekteringen af ​​vulkansk gas fra et sådant borehul er en anden uafhængig bekræftelse af tilstedeværelsen af ​​magma nord for Hagafell, som indikeret af seismisk aktivitet og geofysiske modelleringsresultater.

Sandsynligheden for et udbrud er fortsat høj. Overvågning fortsætter for tegn på overfladisk seismicitet og pludselige jordskorpebevægelser, som kan være forløbere for magma, der bryder sin vej til overfladen. I skrivende stund var der ikke observeret sådanne tegn.

Opdateret 15. november kl. 11:30 UTC

Siden midnat er der målt omkring 800 jordskælv, de fleste af dem midt på magmadiget ved Sundhnúk i omkring 3-5 km dybde. Seismisk aktivitet har været konstant siden 11. ^november . Det primære overvågningsfokus på seismisk aktivitet er fortsat i området omkring diget og Grindavík.

Deformationsmålinger viser fortsat deformation i området. De stemmer overens med magma, der stadig strømmer ind i diget. En del af magmadiget ser ud til at størkne, især i kanterne, men ikke ved magmaindstrømningsområdet, som menes at være nær Sundhnúk.

Målinger af svovldioxid (SO ₂ ) ser ud til at vise svingende afgasning på grund af magmadiget, men yderligere målinger er nødvendige for bekræftelse. Analyse af disse data er i øjeblikket i gang i samarbejde med Chalmers Universitet i Sverige.

Det fiberoptiske kabel fra HS Orka, der løber fra Svartsengi vest for Þorbjörn til Arfadalsvík, bliver brugt som en kontinuerlig seismisk målelinje med høj følsomhed. Dette er en ny teknologi, der har udviklet sig i de senere år, og som nu bruges som yderligere målinger i samarbejde med HS Orku og ETH i Schweiz.

Generelt ser situationen ud til at være uændret siden i går. Sandsynligheden for et udbrud anses stadig for høj. I tilfælde af et udbrud er den mest sandsynlige placering ved magmadiget.

Opdateret 14. november kl. 19:20 UTC

Tidligere på ugen installerede IMO-specialister to DOAS-fjernmålingsinstrumenter på Húsafell. Disse instrumenter kan måle tilstedeværelsen og mængden af ​​SO2 i atmosfæren. Et af DOAS-instrumenterne detekterede SO2 i går og i dag ved den nydannede graben, der ligger mellem Sundhnúkagígar og Grindavík. På grund af den lave mængde dagslys kan målingerne være upræcise, og det tog tid at gennemgå dataene og fortolke dem. I de sidste to dage har østenvinde været fremherskende i området, så det kan ikke udelukkes, at den seneste stærk seismicitet har forårsaget frigivelsen af ​​SO2 fra under Fagardalsfjall, da magma på det sted endnu ikke er størknet siden udbruddet i juli 2023 .

Det er svært at vurdere dybden, hvorfra SO2 frigives, da processen er påvirket af magmatryk. Det menes dog, at magmaen skal være i de øverste hundrede meter af skorpen, for at SO2 kan frigives. Dette er en af ​​grundene til, at DOAS-instrumenterne er blevet placeret tæt på Grindavík.

DOAS (Differential Optical Absorption Spectrometer) er et værktøj, der kan detektere svovldioxid i atmosfæren. Metoden er afhængig af synligt lys, som bevæger sig gennem atmosfæren, rammer en sensor i måleapparatet, som derefter analyseres for bestemte farver (bølgelængder), der mangler i spektret. Svovldioxid absorberer visse bølgelængder af lys, hvilket betyder, at lys rammer måleinstrumentet på en anden måde, hvis der detekteres SO2. Sonden scanner visse dele af himlen, og den giver information om koncentrationen af ​​svovldioxid i det scannede område. DOAS-målinger kræver dagslys for at fungere, så det kan være udfordrende at betjene sådanne instrumenter om vinteren i Island.

Opdateret 14. november kl. 12:40 UTC

Siden midnat den 14. november har over 700 jordskælv været lokaliseret langs orienteringen af ​​magma-indtrængningen, hvoraf det største var M 3.1 nær Hagafell. I aftes, 13. november, fandt stress-udløst seismicitet sted tæt på Kleifarvatn, hvor det største jordskælv registrerede M 3,8 kl. 21:09 UTC. I dag forekommer de fleste jordskælv langs magma-indtrængningen, hvor størstedelen er mikrojordskælv, almindeligvis i brænddybder på 3 til 5 km.

Deformationsmålinger, herunder luftobservationer i høj opløsning, satellitradarbilleder og jordbaserede GPS-observationer afslører fortsatte, igangværende jordbevægelser på grund af den igangværende dannelse af magma-indtrængningen. Disse resultater er i overensstemmelse med fortsat, omend meget lavere magmatilstrømning til området for indtrængningen.

Mellem 12. og 13. november er tilstrømningen estimeret til 75 m ³ / s, og den gennemsnitlige dybde til toppen af ​​magma-indtrængningen menes at være omkring 800 m. Tilløbs- og dybdeestimaterne er afledt af modelbaserede beregninger, og de er behæftet med usikkerhed.

Igennem denne periode med vulkansk uro har fokus været kontinuerlig overvågning af seismicitet og jorddeformation i Grindavík – Svartsengi-regionen. For at fremme vores overvågningsmuligheder har vi installeret yderligere GPS-stationer i og omkring Grindavík. De seneste målinger fra disse stationer viser, at den graben-lignende formation stadig dannes og er mekanisk aktiv. For at øge vores evne til at advare om et udbrud har vi desuden installeret jordbaserede SO2-detektorer, der har udsigt over Grindavík og syd for Sundhnúkur.

Sammenfattende er sandsynligheden for et udbrud fortsat høj. Hvis der opstår et udbrud, vil det mest sandsynlige sted være langs retningen af ​​magma-indtrængningen, begyndende som et sprækkeudbrud.

Opdateret 13. november kl. 16:20 UTC

 

Seismiciteten langs magma-indtrængningen fortsætter, selvom størrelsen og intensiteten af ​​aktiviteten er aftagende. Siden midnat i dag den 13. november er der blevet registreret omkring 900 jordskælv. Den seismiske aktivitet er koncentreret om området for indtrængen mellem Sundhnúkur og Grindavík i en dybde på omkring 2-5 km.

Faldende hastigheder for jorddeformation ses i GPS-data fra Grindavík. Satellitradarresultater viser en graben-lignende formation, der skærer gennem en del af Grindavík. Denne funktion blev først identificeret af IMO i satellitradarbilleder tidligt den 11. november.

 

Dette stigende COSMO-SkyMed (CSK) interferogram dækker tidsperioden 3-11 november og viser et omfattende deformationsfelt relateret til diget intrusion, der begyndte om eftermiddagen den 10. november i Reykjanes-Svartsengi vulkanske system. Dette CSK-interferogram og det forrige (spænder fra 2.-10. november) understøttede den vanskelige beslutning, som Civilbeskyttelsen traf om at evakuere byen Grindavík sent fredag ​​aften. Det muliggjorde også modellering af dimensionerne af digets indtrængning (den 11. november), hvilket gav en median digelængde på 15 km og topdybde på mindre end 1 km under overfladen. Billederne viser over 1 m jordforskydning i den vestlige del af Grindavík, forårsaget af udbredelsen af ​​magma-indtrængningen. Fra geodætiske modelleringsresultater konkluderer vi, at (pr. 12. november) det største område af magma-opstrømning er hentet tæt på Sundhnúkur, 3,5 km nord-nordøst for Grindavík.

Ny geodætisk modellering udføres i øjeblikket ved hjælp af et ICEYE-interferogram og GNSS-observationer, der strækker sig over de sidste 24 timer, for bedre at vurdere den igangværende aktivitet og give et estimat af de nuværende magma-tilstrømningshastigheder.

Ifølge vores seneste skøn er vurderingen af ​​vulkanfare i og omkring Grindavík uændret fra den 12. november. Alle overvågningssystemer overvåges tæt i realtid, især nær Grindavík, for tegn på pludselige ændringer. Overvågningsteamet for naturfarer hos IMO arbejder med maksimal overvågning, mens Department of Civil Protection and Emergency Management koordinerer kortvarig, midlertidig adgang til Grindavík i dag, den 13. november.

Skøn over de lodrette forskydninger forårsaget af diget under dets indledende udbredelse fra fredag ​​eftermiddag til lørdag morgen. Forskydningerne blev estimeret ved at kombinere ICEYE og COSMO-SkyMed pixel offset tracking resultater.

Opdateret 12. november kl. 12:30 UTC

 

Siden morgenen den 11. november har seismisk aktivitet relateret til magma-indtrængningen været nogenlunde konstant. Siden midnat den 12. november er der registreret omkring 1000 jordskælv i diget, og alle har været under M3,0 i styrke. Den mest seismiske aktivitet har fundet sted i regionen nord for Grindavík. De fleste jordskælv er i en dybde på 3-5 km svarende til den nederste del af digets indtrængning.

GPS-målinger, der dækker de seneste 24 timer, viser, at deformationen i forbindelse med digeindtrængningen, der blev dannet fredag ​​den 10. november, er aftaget. Dette kan være en indikation af, at magma bevæger sig tættere på overfladen, nye modeller vil blive kørt, så snart nye data kommer ind for at opdatere modellen.

Det var en fælles vurdering fra mødet, baseret på de seneste data, at der er plads til midlertidige foranstaltninger under kontrol af Department of Civil Protection and Emergency Management for at indsamle fornødenheder til beboerne og varetage akutte ærinder i Grindavík og omegn. areal. Under sådanne operationer er det nødvendigt at øge områdets årvågenhed gennem yderligere overvågning med det formål at forbedre påvisningen af ​​magma, der når overfladen. Det var forskernes opfattelse, at det ville være tilrådeligt at påbegynde disse operationer med det samme, da usikkerheden om begivenhedens fremskridt vokser, som dagen skrider frem. Den endelige beslutning om, hvorvidt disse handlinger vil blive truffet, og deres gennemførelse er i hænderne på den offentlige sikkerhed og politimesteren på Suðurnes.

I lyset af denne fælles vurdering har politimesteren i Suðurnes besluttet at tillade indbyggere at dele af et begrænset område i Þorkötlustaðahverfi, og det er kun for at hente vitale genstande, kæledyr og husdyr. Dette vil blive organiseret og kontrolleret af politiet. Denne tilladelse gælder kun for Þorkötlustaðahverfi. Bemærk, en særlig operation er i gang med at hente alle heste i området nord for Austurver.  

 

 

Denne nyhed er blevet opdateret siden de seneste oplysninger fra politimesteren i Suðurnes.
Opdateret 11. november kl. 18:30 UTC

Klokken 18.00 i dag, den 11. november, sluttede et statusmøde mellem forskere ved det islandske meteorologiske kontor, Islands Universitet og Institut for Civilbeskyttelse og Beredskab. Formålet med mødet var at diskutere de seneste målinger af seismicitet og jorddeformation i Grindavík-regionen, udover at gennemgå de nyeste geofysiske modeller og farevurderinger. Fra kombinerede vurderinger af satellitradarbilleder, jordbaserede GPS-målinger og seismicitet blev det konkluderet, at den igangværende digeindtrængen udgør en alvorlig vulkansk fare. 

Ud fra geofysiske modeller af digets indtrængning vurderes det, at indtrængningen forplanter sig langsomt opad, idet magma menes at være 800 m under overfladen. Den nøjagtige placering af et muligt udbrudssted er ukendt, men digets 15 km længde og orientering giver en god indikation af mulige kilder. Den overordnede vurdering fra statusmødet var, at sandsynligheden for et vulkanudbrud er stor, og at et udbrud kunne være muligt på en tidsskala på blot dage. Baseret på digets udstrækning kunne magma dukke op fra dens sydlige del, lige uden for Grindavik. Derfor er sandsynligheden for et ubådsudbrud også øget, så der skal forberedes mulighed for eksplosiv aktivitet. Der er defineret et fareområde ud fra digets placering, som vist på kortet.

Statuskort, der viser placeringen af ​​digets indtrængen baseret på kombineret satellitradarbilleder, GPS-målinger og geofysisk modellering.

Opdateret 11. november kl. 12:00

 

Siden midnat er der målt omkring 800 jordskælv i den region, hvor magma-indtrængningen finder sted. Jordskælvets aktivitet er aftaget en smule de seneste timer, men den er fortsat høj. De fleste af de seneste jordskælv har fundet sted tæt på Grindavík, hvor den sydvestlige ende af det magmatiske dige skønnes at være placeret.

Analyse af jordskælvene fra i dag og i går er i gang. Målet med dette arbejde er bedre at forstå udviklingen af ​​magma-indtrængningen. I øjeblikket tyder data på, at magma-indtrængningen strækker sig fra Stóra-Skógsfell i nord til Grindavík i syd, hvor den strækker sig under havet. I overensstemmelse med de seneste foreløbige modeller, ved hjælp af de seneste satellitdata indsamlet i aftes, er den laveste dybde af toppen af ​​magma-indtrængningen nord for Grindavík 1,5 km. Fælles fortolkning af jord- og satellitmålinger indikerer, at størrelsen af ​​magma-indtrængningen og hastigheden, hvormed den bevæger sig, er flere gange større, end der tidligere er blevet målt på Reykjanes-halvøen. Vores vurdering er, at et udbrud, hvis det skulle ske, vil stamme fra den nordlige side af magma-indtrængningen. Det betyder, at der er større sandsynlighed for, at et udbrud begynder tæt på Sundhnjúkagígur.

Forskere mødes regelmæssigt for at fortolke dataene og opdatere de nyeste modeller og farevurderinger. Der afholdes et møde for journalister kl. 12.00 i Institut for Civilbeskyttelse og Beredskab. De nuværende forhold og fremtidige scenarier vil blive diskuteret.

Sandsynligheden for et vulkanudbrud i den nærmeste fremtid vurderes at være betydelig.

 

Gennemgået jordskælv siden kl. 21 i går aftes.

Opdateret 10. november kl. 23:30

 

Der er sket væsentlige ændringer i den seismiske aktivitet målt nær Sundhnjúkagígar nord for Grindavík og deformation observeret på Reykjanes-halvøen i eftermiddag. Den seismiske aktivitet har bevæget sig sydpå mod Grindavík. Baseret på hvordan den seismiske aktivitet har udviklet sig siden kl. 18.00 i dag, sammen med resultater fra GPS-målinger, er der en sandsynlighed for, at en magma-indtrængning har strakt sig under Grindavík. I lyset af dette resultat har politimesteren i Suðurnes i samarbejde med civilbeskyttelsesmyndighederne besluttet at evakuere Grindavík. Et nødniveau for civilbeskyttelse er nu i kraft. Dette er ikke en nødevakuering. Beboere i Grindavík rådes til at gå forsigtigt frem.

På nuværende tidspunkt er det ikke muligt at afgøre præcist, om og hvor magma kan nå overfladen. Noget tyder på, at en betydelig mængde magma bevæger sig i et område, der strækker sig fra Sundhnjúkagígum i nord mod Grindavík. Mængden af ​​involveret magma er betydeligt mere end hvad der blev observeret i de største magma-indtrængninger i forbindelse med udbruddene ved Fagradalsfjall. Yderligere data indsamles for at beregne modeller, der giver et mere præcist billede af magma-indtrængningen. Det er på nuværende tidspunkt ikke muligt at sige, hvornår dette arbejde vil være afsluttet.

 

Opdateret 10. november kl. 20.00

 

Den seismiske aktivitet, der i øjeblikket måles ved Sundhnjúkagígar, forekommer inden for et område omkring 3 km nordøst for Grindavík. De laveste jordskælv, der er målt nu, er i en dybde på omkring 3-3,5 km.

De tegn, der kan ses nu ved Sundhnjúkagígar, ligner dem, der blev set på tærsklen til det første udbrud ved Fagradalsfjall i 2021 og minder meget om den seismiske aktivitet, der blev målt omkring en måned før det udbrud. Det mest sandsynlige scenarie nu, når man tager den aktivitet i betragtning, der kulminerede i begyndelsen af ​​den 19. marts ²⁰²¹ , er, at det vil tage flere dage (i stedet for timer) for magma at nå overfladen. 

 

Jordskælv den 10. november (indtil kl. 18.48). Det islandske meteorologiske kontors seismiske netværk er vist med trekanter. Fire seismiske stationer omkring den aktuelle seismiske aktivitet har vist en stor stigning i rysten siden kl.

Opdateret 10. november kl. 18.30

 

Nationalkommissæren for det islandske politi har i samråd med politichefen i Suðurnes erklæret en civilbeskyttelses-alarmfase på grund af den intense jordskælvsværm, der begyndte kl. 15 i dag ved Sundhnjúkagígar, nord for Grindavík. Der er mulighed for større jordskælv end man har oplevet hidtil, og dette hændelsesforløb kan føre til et udbrud. Civilbeskyttelsesberedskabsfasen betyder, at risikoen er stigende, og der bliver truffet foranstaltninger for at sikre den største sikkerhed for dem, der bor/opholder sig i området. Dette gøres ved at øge forholdsreglerne i det relevante område.

Flyfarvekoden er blevet forhøjet til orange (øget uro med øget sandsynlighed for udbrud). IMO følger situationen nøje. Beboere opfordres til at følge informationen på Almannavarnir .

 

Opdateret 10. november kl. 14.00

 

Tidligere i dag, klokken 12:44, opstod et jordskælv med en styrke på 4,1 nær Sýlingarfell, vest for Sundhnjúkagígar. Kraterne ligger omkring 2-3 km nordøst for Grindavík. En tæt sværm af jordskælv begyndte omkring klokken 07.00 i morges i samme område, og der er registreret næsten 800 jordskælv siden midnat, heraf 9 større end 3. Jordskælvenes dybde er omkring 5 km. Sådanne jordskælvssværme er tidligere blevet registreret i dette område. Det kan ikke udelukkes, at den seismiske aktivitet nær Sundhnjúkagígar skyldes magmabevægelser i dybden.

Magmaophobning fortsætter nær Þorbjörn i samme dybde og med samme hastighed som før. Det er ledsaget af sværmlignende seismisk aktivitet, som det blev bemærket i går og i morges. Mens magmaakkumulering fortsætter, kan der forventes igangværende seismisk aktivitet på grund af stressfrigivelse i området. Jordskælv op til størrelsesordenen M5,5 kan forventes i sådanne sværme, og den seismiske aktivitet kan skifte mellem områder. På dette stadium er der ingen indikationer på, at magma tvinger sig vej til overfladen.

 

Gennemgået jordskælv siden midnat

Opdateret 9. november kl. 12:20

 

Omkring 1400 jordskælv er blevet registreret i de sidste 24 timer. Seismisk aktivitet steg fra midnat, og det seismiske SIL-netværk har detekteret syv jordskælv over M4.0 siden da. Det største jordskælv målte M4,8 klokken 12:46. Det lå vest for Þorbjörn. Det er det største jordskælv siden aktiviteten begyndte den 25. oktober. Syv jordskælv M4.0 eller større i størrelse blev målt i området fra Eldvörp til området øst for Sýlingarfell. Mens ophobningen af ​​magma fortsætter, kan der forventes seismisk aktivitet på Reykjavík-halvøen, fordi magma-indtrængningen forårsager øget spænding i området.

Ifølge GPS-data ved midnat fortsætter stigningen i området. GPS-dataene bliver gennemgået i forhold til den seismiske aktivitet i aften. Siden inflationens begyndelse og frem til i dag har stigningen været nogenlunde jævn, selvom der er observeret en acceleration af processen mellem dage. Den seismiske aktivitet i nat og i morges er et eksempel på denne episodiske seismiske aktivitet, der kan forventes, mens magmaakkumulering er i gang. At der nu er større jordskælv end tidligere i området, betyder ikke nødvendigvis en øget hastighed af magma-akkumulering.

 

Gennemgået jordskælv siden midnat i nat

Opdateret 8. november kl. 14.40

 

Cirka 1200 jordskælv er blevet målt i de sidste 24 timer, de fleste af dem i området mellem Þorbjörn og Sýlingafell, svarende til dagen før. Det største jordskælv var M3.4 kl. 12.31 i nat, lige syd for Þorbjörn. Den seismiske aktivitet fortsætter i samme dybde som før. Det er sandsynligt, at seismisk aktivitet vil fortsætte og være episodisk i intensitet, mens magmaakkumulering er i gang. 

Opløftningen fortsætter med samme hastighed som før ifølge satellit- og GNSS-data. Interferogram (InSAR) for perioden 28. oktober – 6. november, der viser næsten lodret bevægelse, bekræfter dette, men det viser også forskydninger på grund af fejlbevægelser forbundet med den seismiske aktivitet. Opdaterede modeller baseret på de samme data estimerer, at magma fortsætter med at akkumulere i en vandret tærskel i en dybde på omkring 5 km, og siden begyndelsen af ​​inflationsbegivenheden (27. oktober) er den gennemsnitlige tilstrømning estimeret til omkring 5 m ³ /s (usikkerhed er ±2 m ³ /s)

 

Interferogram (InSAR) for perioden 28. oktober – 6. november viser, at deformationen i den periode er omkring 7 cm. SW for bjerget Þorbjörn er en offset i deformationssignalet forårsaget af fejlbevægelser fra jordskælv.

Opdateret 7. november kl. 13:30

 

Der har været omkring 900 jordskælv i de sidste 24 timer, de fleste af dem i området mellem Þorbjörn og Sýlingafell. Det største jordskælv var M2,9 og fandt sted omkring klokken 7 i morges. Den seismiske aktivitet forbliver på samme dybde som før.

Ifølge satellitdata behandlet omkring kl. 17 i går og dækker perioden mellem 4.-6. november, bekræfter det, at løftningen fortsætter omkring Þorbjörn. De samme data viser ingen tegn på magmaakkumulering i Eldvörp eller nær Sýlingarfell, øst for Svartsengi, hvor seismisk aktivitet er blevet målt i de seneste dage.

Magmaophobning fortsætter i en dybde på omkring 5 km i NW for Þorbjörn. Hvis den 27. oktober betragtes som startdagen for inflationsbegivenheden indtil i dag, har stigningstakten været nogenlunde konstant, selvom der er observeret en acceleration af processen mellem dage. Det er sandsynligt, at seismisk aktivitet vil fortsætte og være episodisk i intensitet, mens magmaakkumulering er i gang.  

 

Gennemgået jordskælvssteder siden den 6. november og i dag indtil kl.

Opdateret 6. november kl. 13:15

 

I de sidste 24 timer er omkring 1300 jordskælv blevet opdaget på Reykjanes-halvøen, hvoraf tre jordskælv var over M3. Det største jordskælv var M3.6 i morges og lokaliserede 3 km NØ for bjerget Þorbjörn.

Deformationsdata viser, at stigningen fortsætter i området, og der er indikationer på GNSS-observationer om en stigning i inflationsraterne siden 3. november. Siden starten af ​​inflationen er stigningen ved GNSS-stationen ved Þorbjörns bjerg nået 7 cm. Deformationen er forårsaget af en indtrængning af tærsklen på omkring 5 km dybde. Modellering, baseret på data siden 27. oktober, indikerer, at volumenændringen forbundet med denne inflationsbegivenhed har nået næsten det dobbelte af volumenændringen forbundet med de fire tidligere inflationsbegivenheder i samme område mellem 2020-2022. Indstrømning af magma/magmatiske væsker ind i karmlegemet er estimeret til ca. 7 m3/s, hvilket er ca. fire gange større end den højeste tilstrømning, der er estimeret under tidligere inflationsbegivenheder her.

Mens inflationen fortsætter, kan øget seismicitet i området forventes fra yderligere stressændringer induceret i skorpen. 

Data fra GNSS station ved Mt. Þorbjörn. Grafen nederst viser stigningen.

 

Opdateret 4. november kl. 23:30

 

Efter klokken 17.30 i går faldt den seismiske aktivitet betydeligt. I de sidste 12 timer er der registreret omkring 900 jordskælv, alle under M3.0. Aktiviteten efter midnat har primært været placeret ved Sundhnjúkagígar – NØ for Þorbjörn, samt vest for Eldvörp.

Seismiciteten er faldet betydeligt siden i går, men udviklingen af ​​jordskælvets størrelse, antallet af jordskælv og deres placering er sammenlignelig med udviklingen, der tidligere er set relateret til magmaophobning i nærheden af ​​Þorbjörn.

De seneste deformationsdata viser, at løftningen fortsætter i området. Denne stigning menes at skyldes magmaophobning NV for Þorbjörn i 4-5 km dybde. Mens denne magma-akkumulering fortsætter, kan øget seismicitet i området forventes fra øgede spændinger i skorpen. Stenfald kan forekomme efter store jordskælv, så der skal udvises forsigtighed ved stejle skråninger.

Det islandske meteorologiske kontor fortsætter med at overvåge området tæt og mødes med civilbeskyttelsesagenturet for at diskutere situationen. Tegn på magma, der kommer mod overfladen, vil fremstå som øget, mere lavvandet seismicitet og hurtig skorpedeformation ved overfladen samt vulkansk tremor, som er en høj grad af mange små jordskælv. På nuværende tidspunkt kan der ikke ses klare tegn på noget af dette, men situationen kan ændre sig med kort varsel.

Jordskælv (cirkler) med styrke over 1,5 fra midnat den 3. november til kl. 10.45 den 4. november. Farvebjælken til venstre viser tidspunktet for jordskælvene, og størrelsen af ​​cirklerne repræsenterer begivenhedernes relative størrelse. Placeringer af seismiske stationer (trekanter) og GPS-deformationsstationer (firkanter) er også vist.

 

Opdateret 3. november kl. 15.00

Et jordskælv med en styrke på 4,3 blev opdaget kl. 13.14 i dag mellem Þorbjörn og Sýlingarfell. Endnu et jordskælv med en styrke på 3,5 blev opdaget kl. 14:01 i Þorbjörn. Disse jordskælv menes at skyldes vedvarende stress i skorpen fra magma-akkumulering under Þorbjörn-bjerget. Der er ikke påvist vulkansk rystelse, og området bliver stadig overvåget nøje.

Opdateret 3. november kl. 13:50

 

Ifølge målinger fra kl. 11.00 i dag fortsætter hævningen centreret nordvest for Þorbjörn. Hævningen er forårsaget af en magma-indtrængning i en dybde på omkring 4 km. Seismisk aktivitet fortsætter på Reykjanes-halvøen på grund af ændringer i skorpespændingen forårsaget af indtrængen. En stigning i jordskælvsaktivitet blev registreret efter midnat og om morgenen. Siden midnat er der registreret omkring 1.000 jordskælv i området, hvoraf to er over M3.0 og to over M4.0. Det største jordskælv i den nuværende sværm blev målt kl. 8:06 og var 4,3 stort. De største jordskælv i nat ser ud til at opstille sig i nord-sydlig retning vest for Þorbjörn. Dette sker på tidligere kendte sprækker, hvor spændinger har akkumuleret i forbindelse med pladetektonik og kan krølle på grund af spændinger fra indtrængninger.

Der er i øjeblikket ingen klare tegn på, at magma bevæger sig tættere på overfladen. Tegn på, at magma er på vej op til overfladen, vil dukke op i mindre seismisk aktivitet og stigende rysten, som er en høj frekvens af små jordskælv. Samtidig skal pludselig deformation af overfladen måles med GPS-målinger. Udviklingen af ​​denne begivenhed følges nøje, da begivenhedsforløbet kan ændre sig med meget kort varsel.   

Modelberegninger viser, at indtrængen er lokaliseret nordvest for Þorbjörn, som vist på det medfølgende billede. Den seneste seismiske aktivitet har været over selve indtrængen. Jordskælvene målt ved Eldvörp og øst for Grindavík-vejen skyldes spændinger fra indtrængning af magma fra Þorbjörn, snarere end tegn på magmabevægelser i disse områder.

 

 

Omtrentligt centrum for magma-indtrængning ifølge modelberegninger baseret på GPS- og satellitbilleder sammen med seismisk aktivitet fra 2. november kl. 20.00 til 3. november kl. 12.00 større end M1.0 i størrelse. Modellen antager en kasseformet indtrængen, men dens længde og bredde er behæftet med en del usikkerhed. Modellen vil jævnligt blive opdateret med de nyeste data, når den først er erhvervet, og størrelsen og formen af ​​indtrængen kan ændre sig betydeligt, så der er en del usikkerhed omkring modellen.

 

Opdateret 2. november kl. 15.00

 

GPS-data fra de sidste 24 timer indikerer, at stigningen fortsætter med en lignende hastighed i området nordvest for Mt. Þorbjörn. Jordskælvsaktiviteten har været ret stabil, men i går blev der registreret omkring 800 jordskælv i området omkring Þorbjörn, og det største var M3,7 kl. 12:56. Siden midnat i dag er der registreret omkring 400 jordskælv i området, hvoraf det største måler M2,8 kl. 9:51. Mere detaljerede analyser af nyere GPS-data bekræfter, at der dannes en magma-indtrængning i en dybde på 4-5 km under området nordvest for Þorbjörn.  

Det er vigtigt at bemærke, at seismisk aktivitet sandsynligvis vil fortsætte nordvest for Þorbjörn, og jordskælv over M4.0 kan findes i befolkede områder. Udløst seismisk aktivitet kan også forventes i de kommende dage, fordi magma-indtrængningen forårsager øget spænding i området. Stenspyn kan forekomme efter kraftige jordskælv, så det er vigtigt at være forsigtig på stejle skråninger.  

 

Gennemgået jordskælv fra midnat den 1. november til den 2. november kl.

Opdateret 1. november kl. 12:20

 

Den 25. oktober begyndte en intens jordskælvsværm nær Svartsengi, nord for Grindavík på Reykjanes-halvøen. Indtil videre er over 10.500 jordskælv blevet opdaget i sværmen, med over 26 jordskælv, der overstiger størrelsesordenen tre, hvoraf det største var på størrelsesordenen 4,5 den 25. oktober kl. 08:18 UTC.

Det seneste satellitradarbillede, optaget sent den 31. oktober, afslører 5 til 6 cm jordbevægelser over 12 dage, centreret lige nordvest for Mt. Þorbjörn. Samme forskydningssignal ses i kontinuerlige GPS-målinger fra stationer i regionen, begyndende den 27. oktober. De seneste GPS-resultater fra 1. november indikerer, at jordforskydninger fortsætter i regionen. Ved at kombinere seismiske, geodætiske og satellitbaserede observationer konkluderer vi, at en vulkansk indtrængen er placeret på omkring 4 km dybde lige nordvest for Mt. Þorbjörn. På nuværende tidspunkt er der intet, der tyder på, at den vulkanske indtrængen bliver mere lavvandet. Vi forventer, at seismiciteten vil fortsætte nordvest for Mt. Þorbjörn, og dette kan omfatte mærkede jordskælv, der overstiger størrelsesordenen fire. Udløst jordskælvsaktivitet er også mulig i de kommende dage på grund af stressstigninger forårsaget af indtrængen. Dette er en sandsynlig forklaring på den igangværende seismiske aktivitet, der blev opdaget vest for Þorbjörn i Eldvörp den 1. november. Udløst seismicitet er også mulig på grund af de langsigtede virkninger af magmaakkumulering under Fagradalsfjall.

Satellitbaseret InSAR-billede af Reykjanes-halvøen, der strækker sig fra 19. til 31. oktober. Dette billede giver et indblik i jordens deformation i løbet af de sidste 12 dage. Det største deformationssignal er centreret nordvest for bjerget Þorbjörn. Fra GPS-målinger er det tydeligt, at størstedelen af ​​centimeterskalaen jordforskydning er sket siden 27. oktober.

 

Opdateret 31. oktober kl. 17.00

 

I morges kl. 8.40 begyndte en jordskælvsværm ved Þorbjörn, som varede i næsten 2 timer og var usædvanlig intens. Det største jordskælv i sværmen målte M3,7. Aktivitetens centrum var lige øst for midten af ​​den stigning, der er observeret de seneste dage. Jordskælvenes dybde blev anslået til mellem 5 og 1,5 km dybde. Jordskælvsværmen er et tydeligt tegn på magmabevægelser i dybden. GPS-målinger understøtter fortolkningen, selv om stigningen, der startede for omkring fire dage siden, er aftaget. Tidligere i dag var der et møde med civilforsvaret og interessenter på Reykjanes-halvøen, hvor de seneste målinger og mulige scenarier og svar på det aktuelle scenarie blev diskuteret.

Situationen overvåges nøje

IMO følger udviklingen nøje og ser på, om mikroseismisk aktivitet stiger tættere på overfladen, hvilket kan være et tegn på, at magma bryder sig vej gennem jordskorpen. I øjeblikket er der ingen tegn på, at jordskælvsaktiviteten bliver mere lavvandet. Situationen kan dog hurtigt ændre sig, og det er ikke muligt at udelukke et scenarie, der involverer et lavaproducerende udbrud i området nordvest for Þorbjörn. Det er vigtigt at påpege, at magmabevægelser, svarende til dem, der observeres tæt på Þorbjörn, ofte forsvinder og ikke fører til et vulkanudbrud. Ikke desto mindre kunne langvarig riftning og øget (udløst) jordskælvsaktivitet i Svartsengi-området have skabt svagheder i skorpen, hvilket gør det lettere for magma at bevæge sig til lavere dybder.

 

Gennemgået jordskælv fra midnat i dag.

Opdateret 30. oktober kl. 11.30

 

 

Sentinel-satellitdataene, der forventes at blive modtaget i går, er ikke ankommet endnu, men cGPS-dataene i området omkring Svartensgi og Þorbjörn viser, at deformationen stadig er i gang. Deformationshastigheden siden begyndelsen af ​​denne påtrængende begivenhed har været svagt faldende over tid. Foreløbige resultater fra deformationsmodeller tyder på, at den gennemsnitlige dybde, hvor den magmatiske instruktion finder sted, er omkring 4 km.

I løbet af de sidste 24 timer er omkring 1300 jordskælv automatisk blevet registreret på Reykjanes-halvøen. Det meste af denne seismicitet er placeret i en dybde mellem 2-4 km. Det største jordskælv havde en størrelsesorden M2,7 den 29. oktober kl. 11:40 UTC.

Forskere fra det islandske meteorologiske kontor foretager yderligere overflademålinger i området, herunder geokemiske observationer. Der opretholdes regelmæssig kommunikation mellem IMO, HS-Orka og Civilbeskyttelsen, mens denne uro fortsætter.

8-timers løsning til cGNSS THOB-stationen i Þorbjörn, der viser det seneste datapunkt opdateret kl. 08:00 UTC i dag

 

Opdateret 29. oktober kl. 14.00

 

De seneste cGPS-deformationsdata omkring Þorbjörn og Svartengi-området bekræfter, at deformationen, som startede 27. oktober, fortsætter. Som indledningsvis anført, er de igangværende deformationshastigheder højere end i tidligere hændelser, som fandt sted i et lignende område i 2020 og 2022. Samlet set har seismiciteten nord for Grindavík været faldende i løbet af det seneste døgn, og der er ingen væsentlige ændringer i jordskælvsdybderne. Det er dog vigtigt at understrege, at den nuværende deformation kan udløse fornyet seismicitet i området, som kunne mærkes af mennesker.

Nye satellitdata forventes at blive leveret senere i dag, og et nyt interferogram vil blive behandlet, så snart dataene er tilgængelige. Resultaterne vil give os mulighed for at identificere og fortolke de deformationsprocesser, der har fundet sted på halvøen i løbet af de seneste 12 dage. Vi forventede at offentliggøre resultaterne i morgen.

En episode med kompleks vulkan-tektonisk uro påvirker i øjeblikket Reykjanes-halvøen. Det fortolkes som et resultat af flere deformationskilder i dybden, som interagerer og påvirker et bredt område på tværs af halvøen.

8-timers løsning til cGNSS THOB-stationen i Þorbjörn, der viser det seneste datapunkt opdateret kl. 08:00 UTC i dag, den 29. oktober.

 

Opdateret 28. oktober kl. 13.30

 

De seneste cGPS-målinger, sammen med et nyligt erhvervet InSAR-billede over Reykjanes-halvøen, afslører et tydeligt tegn på jordløft, centreret omkring Svartsengi. Dette løftesignal begyndte på et tidspunkt den 27. oktober, og det afspejler en trykstigning, der sandsynligvis er forårsaget af en magmatisk indtrængen i dybden. Midten af ​​løftesignalet er omkring 1,5 km nordvest for Þorbjörn, tæt på Den Blå Lagune. I 2020 og 2022 blev lignende opløftningssignaler detekteret i samme område og med lignende geometri. Dette er nu den femte inflationsbegivenhed i området. Fra en indledende vurdering forekommer det igangværende opløftningssignal hurtigere end tidligere. I øjeblikket er der ingen indikationer på, at magma bevæger sig på lavere dybde. Situationen kan dog udvikle sig hurtigt. For eksempel er der sket betydelige fraktureringer i Svartsengi-området på grund af udløst seismicitet i de seneste dage. En sådan frakturering kunne gøre det muligt for magma at finde veje til mindre dybde.

Samlet set viser de seneste deformationsresultater fra Reykjanes-halvøen en kompleks, igangværende proces med magmabevægelser i jordskorpen. Disse processer påvirker et bredt område, herunder Fagradalsfjall (hvor langsigtet inflation fortsætter), øst for Festarfjall (hvor deformationen ser ud til at være stoppet), og – i de sidste 24 timer – viser et område tæt på Svartsengi inflation.

Den seismiske sværm, der begyndte den 25. oktober nord for Grindavík, har resulteret i over 7.000 jordskælv. Niveauet af jordskælv er reduceret betydeligt, selvom sværmen stadig er i gang, hvilket betyder, at der stadig er sandsynlighed for jordskælv.

Geofysisk modellering er i gang i dag for at bestemme dybden og størrelsen af ​​hævningskilden tæt på Svartsengi. Et ekstra satellitradarbillede vil være tilgængeligt fra Reykjanes-halvøen den 29. oktober. Dette billede skulle give et endnu nærmere indblik i de seneste magmabevægelser og deformationsmønstre på halvøen.

 

 

“Line-of-sight” (LOS)-deformation målt af ICEYE SAR-satellitten mellem den 26. oktober kl. 05:21 UTC og den 28. oktober kl. 05:21 UTC. Satellitdata leveret i samarbejde med ICEYE ( https://www. iceye.com/ ).

 

Opdateret 27. oktober kl. 14.00

 

Det jorddeformationssignal, der er detekteret siden i går i området øst for Festarfjall, bekræftes af de seneste cGPS-data. Den vandrette forskydning i løbet af de sidste par dage er ~ 2 cm som set på FEFC-stationen, og bevægelse er nu også blevet målt på en anden cGPS-station i Selatangar. Et 1-dages interferogram, der spænder over 26. til 27. oktober, afslører ikke nogen væsentlige ændringer i området, men signalet ved FEFC målt i løbet af denne 24-timers periode var mindre end 1 cm, sandsynligvis for lille til at blive detekteret af dette interferogram. cGPS-stationer i Grindavík og nord herfor viser ingen væsentlige ændringer.

Den seismiske sværm nord for Grindavík fortsætter med omkring 1000 jordskælv siden midnat. I alt 5800 eqs er blevet registreret siden starten af ​​aktiviteten. Et jordskælv M4.0 blev målt kl. 04:02 UTC den 27. oktober omkring 2 km nord for Grindavík. Den seismiske aktivitet tolkes som skorpens reaktion på stressændringerne induceret af fortsat magmatisk indstrømning i dybden under Fagradalsfjalls vulkanske system.

 

Forskydning ved cGNSS station FEFC øst for Festarfjall. Blå lodret linje markerer begyndelsen på en digeindtrængning i juli 2023, og den røde linje starter et udbrud nær Litli-Hrútur den 10. juli 2023. De seneste datapunkter viser bevægelse og vandret bevægelse mod SØ.

cGNSS-stationer på Reykjanes-halvøen. Data fra stationerne FEFC og STAN øst for Festarfjall viser bevægelser i det sidste døgn.

Opdateret: 26. oktober kl. 17.00

 

Den seismiske sværm, der begyndte den 24. oktober, fortsætter. Over 4.000 jordskælv er blevet registreret på Reykjanes-halvøen, hvoraf 14 havde en styrke på over M3. Det meste af aktiviteten har fundet sted mellem Stóra-Skogafell og nordøst for Eldvörp. Seismiciteten er placeret mellem 2 og 6 km dybde, med det største jordskælv (M4.5) målt den 25. oktober kl. 08:18 UTC. Forskere ved det islandske meteorologiske kontor (IMO) fortolker den igangværende seismiske aktivitet som udløst af stress induceret af den igangværende deformation ved Fagradalsfjall, som begyndte kort efter sommerens 2023-udbrud. Den igangværende seismiske sværm forventes at fortsætte de kommende dage. På længere sigt kan den fortsatte ophobning af magma under Fagradalsfjall forårsage yderligere seismiske sværme på halvøen.

Jorddeformationsmålinger nær Svartsengi og Grindavík viser ingen ændringer relateret til den igangværende seismiske sværm nord for Grindavík. En enkelt GPS-station (FEFC), øst for Festarfjall, begynder at vise lokaliseret bevægelse i sydøstlig retning. Disse målinger kunne indikere tilstedeværelsen af ​​magma i dybden langs fortsættelsen af ​​digeindtrængninger, der er i nordøstlige retning mod sydvest, som er dannet under Fagradalsfjall siden 2021.

Personale fra IMO fortsætter med at overvåge de seismiske uroligheder nøje. I de kommende dage vil satellitdata blive brugt til bedre at vurdere den rumlige udstrækning af enhver jorddeformation. Målingerne vil også blive brugt til bedre at forstå igangværende geofysiske processer på Reykjanes-halvøen.

 

Gennemgået udløste jordskælv fra 20.-26. oktober.

Skrevet 25. oktober: 

I nat startede en intens jordskælvsværm nær Svartsengi, nord for Grindavík. Over 1000 jordskælv er blevet opdaget der siden midnat, og sværmen er stadig i gang. De største jordskælv, der er registreret, er M3.9 kl. 5.35 UTC og M4.5 kl. 8.18 UTC. Begge disse jordskælv opstod på omkring 5 km dybde. Seneste deformationsdata indsamlet fra flere stationer omkring Þorbjörn/Grindavík området viser ikke signifikante ændringer korreleret med den igangværende seismiske aktivitet. I lyset af de data, der i øjeblikket er tilgængelige, fortolkes denne seismicitet til at være sandsynligt udløst af stressændringer relateret til tidligere påtrængende aktivitet på halvøen. Der er i øjeblikket ingen indikationer på magmavandring under Þorbjörn/Grindavík-området, men situationen kan ændre sig når som helst, og den kan udvikle sig over kort tid fra timer til dage. Som rapporteret i september er en magmatisk indtrængen i gang under Fagradalsfjall.

 

Personale fra IMO fortsætter med at overvåge området tæt og fortolke de nyeste data, efterhånden som de bliver tilgængelige.

Usikkerhedsniveauet for Department of Civil Protection er blevet erklæret på grund af denne seismiske sværm.

 

 

8-timers løsning til cGNSS THOB-stationen i Þorbjörn, der viser det seneste datapunkt opdateret kl. 08:00 UTC i dag.

Gennemgået jordskælvssteder fra midnat til middag den 25. ^oktober .

 

Automatiske lokaliseringer af jordskælv fra midnat til middag den 25. ^oktober .

---

Vulkanaktiviteten er betydeligt reduceret siden i går

Satellitbilleder viser ikke væsentlig jorddeformation indenfor lavabarriererne ved Grindavík

30.5.2024

 

Opdateret 30. maj kl. 14:00 UTC

• Væsentlig reduceret vulkansk aktivitet
• Lavastrømmen hovedsageligt i området omkring Hagafell
• Ingen eksplosiv aktivitet siden i går
• GPS-målinger tyder på, at jorden i Svartsengi-området aftog omkring 15 cm, da magma strømmede derfra
• Mulig gasforurening i S-Island i dag og i hovedstadsområdet i eftermiddag og i morgen
• Gasdistributionsprognose er tilgængelig her
• Betydelig usikkerhed om mængden af ​​gasser fra udbrudsstedet. Realtidsmålinger af luftkvalitet tilgængelige på webstedet for EnvironmentAgency of Iceland

Siden i går eftermiddags er aktiviteten på eruptivspalten ved Sundhnúkur-kraterrækken faldet markant. Aktiviteten i udbruddet har været den samme i nat og i morges, og den vulkanske rystelse har været stabil siden sidst i aftes. Der er ikke set eksplosiv aktivitet siden i går eftermiddags, hvor dampeksplosioner skete på grund af lava, der strømmede ind i sprækker og kom i kontakt med grundvandet ved Hagafell. Aktiviteten er størst tæt på krateret, der var aktivt i længst tid af udbruddet, der startede den 16. marts.

I går eftermiddags en måleflyvning over udbrudsstedet med personale fra fotogrammetri-teamet fra det islandske naturhistoriske institut og de nationale landmålinger af Island. Luftfotograferingsforholdene var udfordrende, da udbrudsfanen lå over en del af lavafeltet, der blev dannet ved udbruddets begyndelse. De data, der er indsamlet under luftundersøgelsen, behandles yderligere sammen med satellitbilleder for at få et klarere billede af lavaudledningens hastighed i de første par timer af udbruddet. Det medfølgende kort viser de groft estimerede konturer af lavafeltet, da det var omkring kl. 17 i går, eller da udbruddet havde varet i omkring fire timer. Placeringen af ​​eruptionsspalten er også angivet med røde stiplede linjer.

(Klik på kortet for at se det større)

GNSS-data viser 15 cm deflation i Svartsengi-området efter digets udbredelse

Satellitbilleder taget tidligt i morges den 30. maj viser ikke nævneværdige bevægelser på revner i Grindavík by. Deformationsmålinger i realtid indikerer også, at der ikke er målt nogen væsentlig deformation der siden i aftes.

GNSS-målinger viser 15 cm deflation i Svartsengi efter digets udbredelse derfra til Sundhnúksgígar-kraterrækken. Diget, der er dannet og nu nærer udbruddet, strækker sig fra bjerget Stóra-Skógfell til bjerget Hagafell. Det anslås, at omkring 15 millioner kubikmeter magma allerede har forladt magmaophobningen under Svartsengi.

Målinger og deformationsdata, der vil være tilgængelige i de kommende dage, vil give mere information om udviklingen af ​​magma-akkumulering under Svartsengi og den mulige udvikling af udbruddet. Meteorologisk Kontor fortsætter med at overvåge området og observere begivenhedens forløb.

Gasspredningsprognose

Vejrudsigten for i dag (torsdag) forudser en vestlig vind, hvor gasforurening forventes at bevæge sig mod øst, hvilket potentielt vil blive bemærket i Ölfus og andre dele af det sydlige Island. En mere sydvestlig vind ventes senere på dagen og fortsætter i morgen (fredag). Det vil få gasforureningen til at bevæge sig mod nordøst og vil kunne opdages i hovedstadsområdet. Der er betydelig usikkerhed om mængden af ​​gasudledninger fra udbrudsstederne. Du kan følge gasspredningsprognosen og realtidsmålinger af forskellige gasser på hjemmesiden loftgaedi.is.

Meteorologisk kontor har modtaget meldinger om vulkansk dis i mange dele af landet, ligesom de er blevet målt på Miljøstyrelsens overvågningsinstrument i Húsavík i det nordlige Island. Ifølge gasspredningsprognosen kan en stor del af landet opleve vulkansk dis i dag. Vulkandis består af svovlpartikler (SO4) dannet på grund af kemiske reaktioner mellem udbrudsfanen og ilt i atmosfæren. Denne proces accelererer, når lufttemperaturen er højere, og solen skinner, som det var tilfældet i går, da udbruddet begyndte. Disse svovlpartikler detekteres ikke af SO2-gasmålere, men er synlige som en gråblå dis, når en vis koncentration er nået. En stigning i fine partikler (PM1 og PM2.5) kan indikere tilstedeværelsen af ​​SO4. Værdierne målt i dag ligger ikke over nogen sundhedstærskel, men du kan overvåge Miljøstyrelsens luftkvalitetsmålere .

 

Opdateret 29. maj kl. 19:10 UTC

• Hoveddelen af ​​eruptivspalten er omkring 2,4 km lang

• Lavaen er strømmet over Grindavík-vejen og Nesvegur-vejen

• Ekstruderingshastigheden ved begyndelsen af ​​udbruddet blev estimeret til 1.500-2.000 m ³ /s

• I nat skifter vindretningen mod sydvest. Gasforurening kan forekomme i hovedstadsområdet i aften og i morgen (30. maj)

 

Der er stadig et betydeligt lavaspringvand på hoveddelen af ​​sprækken, som er omkring 2,4 km lang. Den eruptive sprække strækker sig syd for Hagafell og lava strømmer kraftigt derfra, mest mod syd og vest. Lava er strømmet over Grindavík-vejen mod Þorbjörn og videre langs lavabarriererne vest for Grindavík, der oversvømmer en del af Nesvegur-vejen. En del af lavaen, der flyder mod syd, løber ind i en sprække ved Hagafell, hvor den flyder under jorden, før den kommer frem lige nord for lavabarriererne nordøst for Grindavík. En lavalap nord for Sýlingafell flyder mod vest, og den nærmer sig Grindavík-vejen ved Svartsengi.

Modelberegninger tyder på, at der fra kl. 16:30 UTC er strømmet omkring 14 millioner m ³ /s magma fra magmareservoiret under Svartsengi til Sundhnúkur-kraterrækken. Deformationshastigheden er faldet betydeligt, men magma fortsætter med at strømme fra magma-reservoiret under Svartsengi til Sundhnúkur-kraterrækken.

 

Kort før klokken 16:00 UTC begyndte eksplosiv aktivitet, da magmaen kom i kontakt med grundvandet, hvor en lava strømmer ind i en sprække ved Hagafell. Magmaet får vandet til hurtigt at blive omdannet til gasformig tilstand (damp), hvilket forårsager dampeksplosioner og tephrafald (aske).

Der er betydelig usikkerhed omkring mængden af ​​gasser fra udbrudsstedet. I nat skifter vindretningen mod sydvest og derfor føres gasforurening mod nordøst og kunne mærkes i hovedstadsområdet i nat og i morgen (torsdag). Gasfordelingsprognose kan ses her og realtidsmålinger af forskellige gasser på loftgaedi.is

 

(Klik på kortet for at gøre det større)

 

Opdateret 29. maj kl. 14:50 UTC

• Et vulkanudbrud startede ved Sundhnúkur-kraterrækken kl. 12:46 UTC i dag

• Lavaen flyder over Grindavík vej

• Eruptivspalten er nu omkring 3,4 km lang

• Ekstruderingshastigheden er groft estimeret til 1.500-2.000 m ³ /s

• Seismisk aktivitet er faldet hurtigt

 

Det ser ud til, at det meste af kraften i udbruddet nu er i den sydlige ende af sprækken, der åbnede tidligere i dag. Ifølge oplysninger fra kystvagtens overvågningsflyvning er der en ret intens lavastrøm omkring Hagafell mod øst og derefter sydpå mod Melhólsnáma.

Den sydligste åbning af sprækken er nu mindre end en kilometer væk fra lavabarriererne nord for Grindavík.

Det første skøn fra videnskabsmænd er, at starten på dette udbrud er kraftigere end ved tidligere udbrud i området, men ekstruderingshastigheden er groft estimeret til 1.500-2.000 m ³ /s.

Opdateret 29. maj kl. 14:15 UTC

The lava has flowed about 1 km to the west and there is a considerable flow south of Stóra-Skógfell towards Grindavík road. At just over 14 o’clock the volcanic plume reached about 3.4 km to the air. Another volcanic fissure opened to the west of the largest crater that formed in the eruption which started on 16 March 2024. The extrusion rate is roughly estimated to be 1.000 m³/s.

Gas pollution will be towards southeast and later today towards east and could therefore be felt in Selvogur and Ölfus. The wind direction will change tonight to the southwest and thus gas pollution will be carried to the northeast and could be felt in the capital area tonight and tomorrow (Thursday).

 

Updated 29. May at 11:40 UTC

 

Intense seismic activity is ongoing on the Sundhnúkur crater row. A magma propagation might be starting or has started, and a volcanic eruption could follow.  

 

Updated 24. May at 16:00 UTC

• Strong wind into the night could affect the sensitivity of seismic sensors.

• Deformation data show that land uplift by Svartsengi continues

• About 18 million cubic meters of magma have been added to the magma reservoir since 16 March.

• Still increased likelihood of another dike propagation and an eruption

• Sundhnúkur crater row still the most likely location for a volcanic eruption

• Eruption precursor time could be very short

 

Around 140 earthquakes have been detected in the unrest area in the last two days, all measuring below M2.0. Most of the earthquakes are located either in the area between Mt. Stóra-Skógfell and Mt. Hagafell or to the south of Mt. Þorbjörn. Today fewer earthquakes have been detected in the area compared to previous days. This is due to strong winds that affect the sensitivity of the seismic sensors to measure the very smallest earthquakes. The weather is expected to continue to affect the sensitivity of the seismic sensors into the night but does not affect other sensors used for monitoring the area.

Deformation data shows steadfast and continued uplift in the Svartsengi region, indicating that magma continues to accumulate there at depth. Model calculations estimate ~18 million cubic meters have accumulated there since March 16^th when the last eruption began. The total volume of magma accumulated is more now than in recent previous events. This means that pressure in the system continues to increase and therefore it can be concluded that there are still considerable odds of a new dike propagation followed by an eruption. The timing of when this would happen is however quite uncertain, but the precursor could be very short.

The graph shows the estimated amount of magma that has accumulated under Svartsengi between the volcanic eruptions or magma intrusions that have occurred since November 2023. The slight changes visible on the graph are within the margin of error and have been observed before during the magma accumulation proces, indicating that magma production has remained stable and no significant changes have occured in magma flow under Svartsengi since November 2023.

 

Updated 21. May at 17:30 UTC

• Magma accumulation beneath Svartsengi continues at a stable rate

• About 17 million m3 have been recharged into the magma accumulation zone since the onset of the last eruption (16 March)

• Still increased likelihood of another dike propagation and an eruption

• Precursory time prior to an eruption could be short

 

Around 200 earthquakes were detected in the unrest area during last weekend, most of them below M1.0. This is like the seismicity during last week when around 40 to 80 earthquakes were measured each day. Most of the earthquakes are located either in the area between Mt. Stóra-Skógfell and Mt. Hagafell or south of Mt. Þorbjörn.

Magma accumulation continues beneath the Svartsengi region and uplift also continues at a steady rate there. Minor changes in rate can be seen between days on the following graphs but overall, the trend continues at a steady rate.  At this point it is still assumed that there is increased likelihood of a dike propagation and/or an eruption at the Sundhnúksgígar crater row.

Last news update reported increased micro seismicity over the last weeks in the area south of Mt. Þorbjörn and west of Grindavík. It was also mentioned that it would be possible that magma might find its way through weaknesses in the crust there. At this point, this scenario is considered very unlikely. That interpretation is based on new geodetic modelling and other data discussed at a scientific meeting yesterday, 21 May.

This gradual increase in seismicity is probably a sign of stress release in and around the dike intrusion at the Sundhnúksgígar crater row due to increased pressure in the magma accumulation zone beneath Svartsengi.

The most likely scenario is still considered to be a dike propagation and/or eruption at the Sundhnúksgígar crater row.

HS Orka monitors pressure changes in boreholes in the Svartsengi region. Sudden change in pressure has been one of the precursory signals seen prior to last dike propagations and eruptions. It has previously been reported that the signs of a new dike propagation would be localized seismic swarm, changes in the rate of deformation and pressure changes in boreholes. Minor pressure fluctuations were observed yesterday in a borehole in the Svartsengi region, but there was no significant increase in seismicity or deformation at the same time. Therefore, it was not assessed that the pressure fluctuations were a sign of a dike propagation.

 

Updated 17. May at 17:00 UTC

• Magma accumulation beneath Svartsengi remains stable.

• About 16 million cubic meters of magma have been added to the magma reservoir since 16 March.

• Continued increased probability of another dyke propagation and another volcanic eruption.

• Sundhnúkur crater row still the most likely location for a volcanic eruption.

• Notice of an eruption could be very short.

• Necessary to be prepared for other scenarios than a volcanic eruption on the Sundhnúkur crater row.

 

Around 50 earthquakes were detected in the area around the dyke intrusion yesterday, 16 May, most of them below M1.0.  This is similar to the seismic activity that has been detected in recent days, but about 50 to 80 earthquakes have been measured per day, most of them occurring in two main areas, between Stóra-Skógfell and Hagafell and south of Þorbjörn.

Magma accumulation continues beneath Svartsengi and land uplift is ongoing at the same rate as before. Therefore, there is still an increased probability that in the coming days a new dyke intrusion and another volcanic eruption in the Sundhnúkur crater row could occur.

The last eruption in the Sundhnúkur crater row started on 16 March. In the 62 days that have passed since then, about 16 million cubic meters of magma have been added to the magma reservoir beneath Svartsengi. This is the longest period of magma accumulation since this scenario began at the end of October 2023.

 

Updated hazard assessment and possible scenarios.

 

The Icelandic Meteorological Office has published an updated hazard assessment map that is valid until 21 May barring any developments. The hazard of gas pollution in connection with an increased likelihood of another volcanic eruption is now considered high in area 7 but was previously considerable. Due to the change, the overall hazard in the area is now assessed as considerable (organge) but was previously moderate (yellow). Hazard due to gas pollution in other areas is unchanged from last week and is assessed as considerable. Due to increased microseismicity in area 4 the hazard of earthquakes has been raised.

IMO has also updated the scenarios that are considered most likely.

Scenario 1 Volcanic eruption between Sýlingarfell and Stóra-Skógfell (Central part of zone 3 on hazard assessment map). Similar location as where the eruptions started on December 18 2023, February 8 and March 16 2024.

 

• Probable precursors are localized, small seismic swarm between Stóra-Skógfell and Sýlingarfell, acceleration of deformation and pressure changes in boreholes in the area.

• Very short notice (less than 30 minutes), even no notice due crust already being fractured.

• Lava could reach Grindavíkurvegur in 2 to 4 hours.

 

 

Scenario 2 – Volcanic eruption south or southwest of Hagafell (Southernmost part of zone 3 on the hazard assessment map). Similar location as where the eruption started on January 14, 2024.

 

•  Probable precursors are a small seismic swarm that starts near Stóra-Skógfell or Sýlingarfell and moves south, acceleration of deformation and pressure changes in boreholes in the area.

• The notice of an eruption in this zone would probably be longer than in scenario 1, but is is uncertain how much longer.

• Lava could reach the barriers by Grindavík in about 1 hour.

• A dyke intrusion extending south of Hagafell will probably cause significant fissure movements in Grindavík.

 

 

The total amount of magma in the magma reservoir beneath Svartsengi has never been more than before 10 November 2023. Other scenarios need to be considered if magma accumulation continues without magma propagation or volcanic eruption.

Hitherto, the amount of magma that has been added to the magma reservoir between magma propagations or eruptions has been considered. In the context of increasing magma pressure in the magma reservoir beneath Svartsengi, it is necessary to consider the total amount of magma estimated to be present. 

Between 25 October and 10 November 2023, more than 10 million m³ of magma accumulated beneath Svartsengi. It is estimated that about 80 million m³ of magma propagated from the magma reservoir during the formation of a 15 km long dyke intrusion on 10 November. It can therefore be assumed that about 70 million m³ of magma was present in the magma reservoir beneath Svartsengi at that point. Magma accumulation has continued uninterrupted since then and magma has outflowed at least five times from Svartsengi to the Sundhnúksgígar crater row. Four of these five times have resulted in an eruption.

Each magma propagation or volcanic eruption has not exhausted the magma accumulation area, and therefore the initial status of magma accumulation beneath Svartsengi has varied in each cycle after November 2023, as shown in the figure below.

Caption: Graph showing the development of magma accumulation and the estimated total amount of magma in the magma reservoir beneath Svartsengi since October 25. Each magma propagation did not exhaust the reservoir, and therefore the starting status of accumulation beneath Svartsengi will vary in each cycle after November 2023. The graph shows that the total amount of magma has never been higher since the forming of the 15 km long dyke on November 10.

There are some similarities between this sequence of events in the Sundhnúkur crater row and the one that occurred in the Krafla Fires that started in 1975, Over 10-year period, there were 20 magma propagations, 9 of which ended in an eruption. During the Krafla Fires, the propagations all fed into the same dyke intrusion, but varied in size. Experience from the Krafla Fires suggests that as the number of magma propagations increases, more pressure is needed to trigger them. Therefore, it must be considered likely that magma will flow again from the magma reservoir beneath Svartsengi into the Sundhnúkur crater row.

Caption: Figures showing the correlation between the formation of a dyke intrusion and the land elevation in the middle of the Krafla caldera. The lower figure shows the elevation of the measurement point within the caldera, while the upper figure shows the distance (km) of events from the Krafla caldera in each event, with red color representing a volcanic eruption (Páll Einarsson and Bryndís Brandsdóttir, 2021).

The total amount of magma in the reservoir beneath Svartsengi has never been higher since the 15 km dyke instrusion formed on 10 November. As more time passes without a new magma propagation into the Sundhnúkur crater row, the likelihood of magma finding its way to other areas where weakness is found in the Earth’s crust increases.

Micro-seismic activity has been ongoing for the past few weeks in the area south of Þorbjörn, in the large rift valley by Grindavík. In this area, there are weaknesses in the Earth’s crust and thus magma could reach the surface there. The fact that magma flows from the magma reservoir to the area south of Þorbjörn is at this point in time a less likely scenario than the ones mentioned above. Therefore, this scenario is not taken into account in the updated hazard assessment. The Icelandic Meteorological Office will collect and process data over the next few days to shed a better light on this possibility.

The map shows earthquakes from 10-16 May. The upper graph shows the magnitude of the earthquakes and the lower graph show the number of earthquakes each day for the same period.

 

Updated 16 May at 13:00 UTC

• Magma accumulation beneath Svarstengi continues at a steady rate.

• About 16 million cubic meters of magma has been added to the magma reservoir.

• Increased probability of another dyke propagation and/or a volcanic eruption in the coming days.

• Sundhnúkur crater row is the most likely location of another eruption.

• An eruption could start with very little (or no) warning time

 

Around 80 earthquakes were detected in the area around the dyke intrusion yesterday, 15 May, most of them below M1.0. This is similar to the seismic activity that has been detected in recent days, but about 50 to 80 earthquakes have been measured per day, most of them occurring in two main areas, between Stóra-Skógfell and Hagafell and south of Þorbjörn. Signs of new magma migration from the Svartsengi reservoir to the previous diking area, may comprise localized small seismic swarms in and around the intrusion, rapid changes in deformation and pressure changes in boreholes in the area.

Magma accumulation continues beneath Svartsengi and land uplift is ongoing at the same rate as that observed since early April 2024. Therefore, there is still an increased probability that in the coming days a new dyke intrusion and another volcanic eruption in the Sundhnúkur crater row could occur.

Prior to previous dyke intrusions and volcanic eruptions, about 8 to 13 million cubic meters had been added to the magma reservoir before the reservoir failed and magma flowed from this to the Sundhnúkur crater row. Now, the amount of magma that has been added is more than the upper limit, as a total of ~16 million cubic meters have been added to the reservoir since 16 March, when the last eruption started.

Lesson learned from the Krafla Fires was that as the number of dyke propagations increases, more pressure is needed to trigger them. Therefore, it must be considered likely that magma will once again flow from the Svartsengi magma reservoir to the Sundhnúkur crater row, but there is an uncertainty as to when sufficient pressure will be reached to trigger a new dyke propagation and/or eruption.

 

 

The graph shows the estimated amount of magma that has been recharged to the  Svartsengi magma reservoir between the eruptions or dyke propagations that have occurred since November 2023. In previous dyking events and eruptions, about 8 to 13 million cubic meters has been added to the magma reservoir before the reservoir failed and magma flowed into the Sundhnúkur crater row. Now the magma amount has surpassed the upper limit, as ~16 million cubic meters have been added to the reservoir since 16 March, when the last eruption began.

 

Updated 13 May at 15:00 UTC

• There is an increased likelihood of a new dike intrusion and another eruption in the coming days.

• The most likely location for a new eruption is the Sundhnúk crater row.

• Warning signs preceding an eruption could be very short.

 

Ground uplift continues in the Svartsengi area at the same rate as previously observed. Since March 16th, when the last volcanic eruption began, ground uplift has reached approximately 20 cm at the GNSS station in Svartsengi. Magma accumulation continues in the reservoir, and the likelihood of a new dike intrusion and a new eruption continues to increase.

In the previous dike intrusions and eruptions over the past several months, approximately 8 to 13 million cubic meters of magma were recharged to the reservoir beneath Svartsengi between events before the magma migrated to the surface towards the Sundhnúk crater row. Now, the volume of magma added since March 16th has exceeded the previously observed upper limit.

Seismic activity is relatively stable between days. In the last week, approximately 50 to 80 earthquakes were recorded per day, mostly occurring in the areas between Stóra-Skógfell and Hagafell and south of Þorbjörn. Most of the earthquakes have magnitudes below 1.0, but isolated earthquakes with magnitudes close to 2.0 have been recorded. Signs of a new dike intrusion are expected to be similar to those previously observed, such as localized seismic activity in and around the dike, fast ground deformation, and pressure changes in nearby boreholes.

The Icelandic Meteorological Office continues its 24-hour surveillance of the area. New eruptive fissures could open in the area between Stóra-Skógfell and Hagafell, and signs of magma migrating towards the surface would likely resemble the initial phases of other recent eruptions in the area. This could occur with little to no warning.

The graph shows the estimated volume of magma that has recharged beneath the Svartsengi area between the series of volcanic eruptions and dike intrusions that began in November 2023. Note that a geomagnetic storm over the weekend disturbed the measurements. (See discussion below.)

Disturbance in GNSS measurements due to the geomagnetic storm

Land uplift is calculated by measuring the change in the amount of time it takes for a signal to travel from satellites orbiting the earth to GNSS receivers on the ground. If the duration of time for the signal to travel between the satellite and the receiver decreases, it indicates that the land has risen.

Over the weekend, one of the most powerful geomagnetic storms in recent years occurred when solar winds from large sunspots on the Sun hit the Earth. The last geomagnetic storm of a similar magnitude occurred on October 30, 2003.

Strong solar winds send charged particles into the Earth’s magnetic field, affecting signal transmissions between GNSS receivers on the ground and satellites. This interference affects the travel time of the signal, causing deformation measurements that could be interpreted as a slowdown in magma accumulation rate. However, this is not the case, as a new data point calculated this morning is at a “normal” location compared to previous measurements. (See graph above).

Disturbances due to geomagnetic storms do not affect the Icelandic Meteorological Office’s ability to provide warnings of imminent dike intrusions or eruptions.

 

Updated 10. May at 18:00 UTC

• There is an increased likelihood of a new dike intrusion and another eruption in the coming days.

• The most likely location for a new eruption is the Sundhnúk crater row.

• Warning signs preceding an eruption could be very brief.

• An updated hazard assessment map has been issued.

 

The trend of land rise at Svartsengi has remained relatively stable since the most recent volcanic eruption ended, with magma accumulation continuing at a similar rate. As of today, it is estimated that approximately 14 million cubic meters of magma has been added to the magma chamber since the eruption began on March 16th.

In the dike intrusions and eruptions over the past few months, approximately 8 to 13 million cubic meters of magma was added to the chamber beneath Svartsengi before it exited the chamber and travelled towards the Sundhnúk crater row. Now, the amount of magma added has surpassed the previously observed upper limit. Observations from the Krafla eruptions can add context to this behavior, revealing that, as more dike intrusions occur, more pressure is required to initiate them. Therefore, it is likely that the magma chamber beneath Svartsengi will eventually feed another intrusion into the Sundhnúk crater row. However, there is uncertainty about when sufficient pressure will be reached to initiate a new dike intrusion and potentially an eruption if magma reaches the surface.

Graph showing the estimated amount of magma that has accumulated beneath Svartsengi between the eruptions and dike intrusions that have occurred on Reykjanes since November 2023.

The Icelandic Meteorological Office continues its 24-hour surveillance of the area to closely monitor the activity. New eruptive fissures could open in the area between Stóra-Skógfell and Hagafell and may resemble the initial phases of other recent eruptions in the area. This could happen with little to no warning. Signs of a new dike intrusion would be similar to those previously observed: localized earthquakes in and around the dike, accelerated deformation, and pressure changes in nearby boreholes.

Increased seismic activity has been recorded at the Sundhnúk crater row in recent days. This increase in seismic activity is likely a sign that stress is being released in and around the recent eruption site on the Sundhnúk crater row due to increased pressure in the magma chamber beneath Svartsengi.

Last night, the Icelandic Meteorological Office’s 24-hour surveillance team detected an increase in localized seismic activity south of Stóra-Skógfell, in a similar location to where previous eruptions have started. Deformation and pressure measurements, which would indicate a dike intrusion, did not exhibit significant changes. The activity persisted for a relatively short duration, but it cannot be ruled out that a small amount of magma may have been injected there.

Dangerous to be travelling near the Sundhnúk crater row

The Icelandic Meteorological Office has issued an updated hazard assessment. The termination of the last eruption has caused updates in several areas, but the current hazard assessment reflects increased chances of a new dike intrusion and possible eruption.

As the crust between Stóra-Skógfell and Hagafell is heavily fractured, magma is likely to find a clear path to the surface without significant resistance, and therefore, substantial seismic activity may not accompany magma migration through the crust. Therefore, warning times before a new eruption could be very brief or nonexistent, so it is important to exercise extreme caution when travelling to area 3, defined on the Icelandic Meteorological Office’s hazard map. The new risk assessment is valid until May 14th, unless the situation changes.

 

Updated 7. May at 17:45 UTC

• Land rise continues in Svartsengi

• The rate of magma accumulation remains similar to that observed in recent weeks

• Visible activity in the active crater has decreased in recent days

• There is a growing likelihood that the current eruption may increase in intensity or that a new eruptive fissure may open

• Warning of increased volcanic activity or a new eruption could be very brief

• The gas dispersion forecast can be followed here

• The hazard assessment remains unchanged

 

The eruption at the Sundhnúk crater row continues. Lava continues to flow a short distance from the active vent, but activity within this crater is decreasing. Over the past week, little to no change has been observed in the southern part of the lava field near the defensive barriers east of Grindavík.

Magma accumulation and land rise continue in Svartsengi. The rate has remained consistent in recent weeks (see figure below). These measurements indicate that pressure continues to rise in the magma chamber. Therefore, a new dike intrusion from the magma chamber beneath Svartsengi towards the Sundhnúk crater row remains possible.

Seismic activity has increased steadily in and around the eruption area over the past week. Most of the earthquakes, which are generally smaller than magnitude 1, are located north of the current eruption site, between Sundhnúk and Stóra Skógfell, south of Þorbjarnar in the large valley near Grindavík, and between Grindavík and the current eruption site. This gradual increase in seismic activity is likely a sign that stress is being released around the eruption site on the Sundhnúk crater row due to increased pressure in the magma chamber beneath Svartsengi.

This figure shows a map with the locations of earthquakes since April 15^th (left), along with automatic magnitudes (top right) and the number of earthquakes per day (bottom right).

These are the most likely two scenarios regarding the continuation of activity at the Sundhnúkur crater row:

 

• New eruptive fissures could open in the area between Stóra-Skógafell and Hagafell, and/or the current eruption site could expand due to a sudden increase in lava flow, which may be comparable to the initial phases of the last volcanic eruption in the area. This could occur with very little to no warning.
• It is also possible that the flow of magma from the magma chamber beneath Svartsengi into the active vent at the Sundhnúkur crater row may increase steadily until there is equilibrium between the inflow of magma into the chamber and the outflow onto the surface.

 

Signs of a new volcanic eruption would likely include a sudden increase in earthquakes in and around the eruption area, an acceleration in deformation, and pressure changes in nearby boreholes. It is important to understand that warning times could be nonexistent or very short, possibly less than half an hour.

The hazard assessment remains unchanged since the last update. In the past week, the risk of possible active lava flows in area 4 (Grindavík) has increased from considerable to high, based on the scenarios now considered most likely.

(Click on the map to see a larger version)

It is difficult to predict when there might be an end to the ongoing sequence of unrest that began in late October

As previously stated, there is still uncertainty about the progression of this episode now that the volcanic eruption has been ongoing for over a month, while magma continues to accumulate in the magma chamber beneath Svartsengi. Although the scenarios outlined above are considered to be most likely, close monitoring is ongoing to determine if magma is seeking paths other than towards the Sundhnúk crater row. Areas north of Stóra-Skógfell and south of Hagafell and Þorbjarnar are being closely monitored.

If magma moves towards the surface outside of the areas where recent eruptions have already occurred, the warning signals are expected to be more significant, manifesting with stronger and more intense seismicity than observed in the lead-up to the most recent eruptions.

 

 

Updated 2. May at 18:00 UTC

• Land rise continues at Svartsengi. Pressure continues to build up within the magma chamber.

• Lava flow from the crater, which has been decreasing in recent days, continues.

• Measurements and simulations indicate that there is significant uncertainty about the future. The likelihood of a new volcanic eruption and/or an increase in the intensity of the eruption at the Sundhnúkur crater row is growing.

• There is a risk that lava may breach the eastern defenses of Grindavík if the eruption’s strength increases again.

• The hazard assessment remains unchanged.

 

Land deformation continues to be measured at Svartsengi, and the rate of uplift has remained stable in recent weeks (see image below). Earlier in the week, there were indications that the rate of land rise might have slowed in the preceding days. However, measurements since then reveal that the rate has remained steady in the context of the past few weeks. Pressure continues to increase within the magma chamber, and there is a risk that the magma chamber beneath Svartsengi will feed a new volcanic eruption.

The graph shows ground movement in the vertical component at the GPS station SKSH in Svartsengi. The measurements indicate that the rate of land deformation has remained steady since the beginning of April. The blue line represents the timing of the magma intrusion, which did not culminate in an eruption, while the red lines represent diking events that resulted in an eruption. The second red line shows the onset of the ongoing volcanic eruption.

Seismic activity has increased along the Sundhnúkur crater row in recent days. These earthquakes are small, likely representing a release of stress within and around the increasingly pressurized magma chamber beneath Svartsengi.

Lava flow from the active crater is significantly lower than it was three weeks ago, and the ccurrent flow rate is measured to be relatively small. However, an eventual increase in flow rate must be considered despite the currently minimal lava flow.

The accompanying map shows changes in the thickness of the lava flow between April 15th, April 25th, and April 30th.

Lava from the crater has been accumulating near Grindavík’s eastern defense wall in recent weeks (L12 on the image above). If the intensity of the eruption increases or new fissures open south of the current eruption site, it is expected that the lava flow will advance towards the eastern defenses of Grindavík. On Saturday, April 27th, small lava flows crossed the defenses east of Grindavík. If the power of the eruption increases again, there is a risk that such occurrences will become more frequent.

These are the most likely two scenarios regarding the continuation of activity at the Sundhnúkur crater row:

• New volcanic fissures could open in the area between Stóra-Skógafell and Hagafell, and/or the current eruption site could expand due to a sudden increase in lava flow, which may be comparable to the initial phases of the last volcanic eruption in the area. This could occur with very little or no warning.

• It is also possible that the flow of magma from the magma chamber beneath Svartsengi into the active vent at the Sundhnúkur crater row may increase steadily until there is equilibrium between the inflow of magma into the chamber and the outflow onto the surface.

Precursory signals of a new volcanic eruption would resemble previous events, with sudden and intense seismic activity within and around the magma chamber and land deformation in Svartsengi.

The hazard assessment by the Icelandic Meteorological Office remains unchanged and is valid until May 7th, unless the situation changes.

Follow the meteorologist’s forecast for gas emissions here.

 

Updated 26. April at 17:30 UTC

• Part of the lava field near the barriers east of Grindavík continues to thicken slowly.

• Ground uplift in the Svartsengi area continues at constant rate.

• As long as the magma continues accumulating in the Svartsengi reservoir, the likelihood for a significant escalation in the eruptive activity in Sundhnúk crater row increases.

• Continued hazard due to gas emissions in the area.

 

The eruption at Sundhnúkur continues with one crater, just east of Sundhnúkur, remaining active as of 5 April. Lava flows travel a short distance to the south of the crater in an open lava channel but progress further in closed channels. Part of the lava field near the barrier east of Grindavík continues to thicken slowly.

Image from the Icelandic Meteorological Office‘s web-camera taken at 4:30 this morning, shortly before sunrise. The camera is located on top of Þorbjörn and looks northeast towards the crater.

Ground uplift in the Svartsengi area continues at constant rate. Analytical models suggest that the amount of magma recharged within the reservoir beneath Svartsengi, since the eruption began on 16 March, is now approaching 10 million m³, as is shown in the graph below.  In previous events, magma started propagating as dike intrusions from the reservoir at 4-5 km depth towards the surface when a threshold of about 8-13 million m³ of recharged magma was reached.

The graph shows the estimated amount of magma that has been recharged beneath the Svartsengi area between volcanic eruptions or magma propagations that have occurred since November 2023.

As long as the magma continues accumulating in the Svartsengi reservoir, the likelihood for a significant escalation in the eruptive activity in Sundhnúk crater row increases.

 

• New eruptive fissures may open up in the area between Stóra-Skógfell and Hagafell and/or the current eruptive fissure may enlarge due to a sudden increase in lava flow, which could be similar to the initial phase of the last eruptions in the area. This could happen with very short, if any, precursors.
• It is also possible that if more magma starts propagating from the Svartsengi reservoir to the Sundhnúks crater row, this could happen gradually until a balance between the inflow rate at depth and the extrusion rate at the surface is reached.

 

There is also a possibility of a new dike intrusion resulting in a new volcanic fissure opening up elsewhere than in the area between Stóra-Skógfell and Hagafell. This scenario is considered less likely than the others, and longer and more intense precursors are expected to occur.

On Wednesday, 24 April, experts from the Icelandic Meteorological Office carried out measurements of gas release from the eruption. It was estimated to be 6-9 kg/s of SO₂, whereas in the last measurement, carried out two weeks ago on 12 April, the gas emission was estimated at 10-18 kg/s. This is not a confirmation that the trend in gas emission from the eruption is reducing. In fact, while the eruption continues, emissions of SO₂ can vary greatly between days (as was observed during the eruptions at Fagradalsfjall). There continues to be a hazard due to gas emission in the area around the crater as well as in settlements in the Reykjanes peninsula, and we advise people in the area to monitor air quality and familiarize themselves with the response to air pollution from the eruption.

 

Volcanic gas pollution (SO₂) in the atmosphere was clearly visible in a satellite image (Sentinel 5p) taken yesterday, 25 April at 14:27 UTC.

The weather forecast predicts northerly winds of 5-10 m/s today, Friday, and gas pollution will be dispersed to the south of the eruption site and could be felt in Grindavík. The weather forecast for gas dispersion is here.

 

Updated 23. April at 18:00 UTC

 

The eruption continues from the single vent which formed just East of Sundhnúkur, in a similar manner since 5 April. Lava continues to extrude and propagate towards the South along open channels, which are clearly visible from the cameras. The lava is also travelling longer distances from the crater through a network of closed tubes, which prevents the lava from cooling by direct contact with the atmosphere. The sector of the lava field which has been propagating towards the South, and reached the protective barriers built East of Grindavík town, has been thickening in the past few days, as shown in the images below. The images show the differences in the lava field profile between 18 and 23 April. The image at the top is taken from the camera owned by the Icelandic Civil Protection which is located at the barrier East of Grindavík and looks toward the part of the lava field which propagated towards Suðurstandavegur at the beginning of the eruption. The image at the bottom is also from a camera owned by the Icelandic Civil Protection and it is located on top of Hagafell hill and is oriented to the South. 

Estimates of the lava extrusion rate show values between 3-4 m3/s since the beginning of April. The last measurements were made on 15 April, so we are now waiting for new acquisitions which will be available next week, to shed light on the level of the current activity and to understand if there have been any significant changes.

Image from the camera, owned by the Icelandic Civil Protection, which is located at the protective barrier East of Grindavík town. The camera is oriented to follow the lava tongue which propagated towards Suðurstrandavegur at the beginning of the eruption. The yellow box indicates where the lava field has been thickening the most over the past few days.

Image from the camera, owned by the Icelandic Civil Protection, which is located on top of Hagafell hill and is oriented towards the south. The yellow box indicates where the lava field close to the potective barrier has been thickening the most over the past few days.

The ground uplift measured around the Svartsengi region continues, indicating that magma accumulates at depth at a stable rate and the total inflow to the reservoir is greater than the outflow feeding the eruption. By using analytical models, constrained by both GNSS and InSAR data, it is assessed that between 7-8 million m3 of magma has been recharged to the Svartsengi reservoir since the eruption commenced on 16 March. In previous events, magma started propagating as dike intrusions from the reservoir at 4-5 km depth towards the surface when a threshold of about 8-13 million m3 of recharged magma was reached.

As long as the magma continues accumulating in the Svartsengi reservoir, the likelihood for a significant escalation in the eruptive activity in Sundhnúk crater row increases. 

 

• New eruptive fissures may open in the area between Stóra-Skógfells and Hagafells and/or the current eruptive vent may enlarge because of a sudden increase in magma flow rate, which might reach levels comparable to those observed at the beginning of the past four eruptions which occurred in the area. If this happens, very short precursors, if any, are expected. 
• It is also possible that if more magma starts propagating from the Svartsengi reservoir to the Sundhnúks crater row, this could happen gradually until a balance between the inflow rate at depth and the extrusion rate at the surface is reached.

 

There is also the possibility that a new dike intrusion will result in the opening of additional eruptive fissures in areas other than between Stóra-Skógfells and Hagafells. This scenario is, however, considered less likely than those previously stated, and if this happens, longer and more intense precursors are expected to occur. 

Updated hazard map

During the scientific meeting this morning, the hazard assessment for the ongoing activity was reviewed. The likelihood of opening of eruptive fissures within Zone 1 (Svartsengi), Zone 4 (Grindavík) and Zone 7 has been reduced from being considerable to low. 

On Friday last week, due to the continued inflation of the Svartsengi reservoir, and the high uncertainty regarding this new situation and possible outcomes, the decision was made to temporarily increase the likelihood for eruptive openings within these areas. However, following the meeting today, it has been agreed that there is currently no evidence for an increased probability of eruptive openings in these areas. 

While the eruption continues, it is assessed that if increased magma flow occurs, the magma will most likely follow the open pathways feeding the current eruption and/or new eruptive fissures may form nearby. For this reason, the likelihood of eruptive openings without warning is still assessed to be very high within Zone 3 (Sundhnúks crater row), which remains unchanged.

 

Updated 19. April at 15:30 UTC

• Ground uplift in Svartsengi continues at a steady rate.

• Since 5 April, only one crater has erupted and lava flow from it has remained relatively stable since then, just over 3 m³/s.

• Continued hazard due to gas emissions. People are advised to monitor air quality.

• The weather forecast for gas dispersion is here

• Continued magma accumulation beneath Svartsengi at current rate increases likelihood of another magma propagation in the coming days or weeks, despite the ongoing eruption.

 

When the eruption started on the 16 March, ground uplift at Svartsengi slowed down considerably and almost stopped. This indicated an equilibrium between magma inflow into the magma reservoir below Svartsengi, and to the surface at the Sundhnúkur crater row (Figure 1).

At the beginning of April, ground uplift began to increase anew, and a similar volume of magma is now being erupted at Sundhnúkur as is accumulated in the reservoir beneath Svartsengi, causing increased magma pressure (Figure 2).  

The current development is new, which is an ongoing volcanic eruption with a relatively stable lava flow at Sundhnúkur crater row at the same time as ground is uplifting in Svartsengi. Therefore, there is more uncertainty now than before about the possible development of the event.

(Image 1)

 

(Image 2)

 

Model calculations indicate that over 6 million m³ of magma has now been added to the magma reservoir beneath Svartsengi since 16 March. In previous events, magma has propagated from Svartsengi when between 8 and 13 million m³ has been added to the reservoir since last event.

The graph shows the estimated amount of magma that has been added beneath Svartsengi between the volcanic eruptions and magma propagations that have occurred since November 2023.

More uncertainty concerning the development of the activity in the next days or weeks.

Hitherto, the general trend in Sundhnúkur area has been increased likelihood of magma propagation and even a subsequent eruption. Now however, a new situation seems to be at hand when a magma propagation could occur during an ongoing eruption. Let’s recall that magma propagation is a sudden and large flow of magma propagating out of a magma reservoir and can culminate with magma reaching the surface. After the magma propagation on 2 March, which did not end in an eruption, marked a change in the activity that had since December been somewhat cyclical.

If magma accumulation continues at a similar rate, the likelihood of another magma propagation increases in the coming days or weeks, even though an eruption is still ongoing. Magma propagation from the reservoir during an ongoing eruption has thus far not been seen before in the area. Therefore, more uncertainty is on the development of the activity in the next days or weeks.

Probable scenario if magma propagation coincides with the current eruption:

 

• Magma propagates from the magma reservoir beneath Svartsengi to the Sundhnúkur crater row, as has happened in the last six times.
• Following the magma propagation, new eruptive fissures could open in the area between Stóra-Skógfell and Hagafell and/or the current eruptive crater could be enlarged due to a sudden increase of lava flow. This could occur at very short or no notice.
• If magma propagation results in new volcanic fissures opening up elsewhere above the magma dike which formed on 10 November, much longer notice is expected, most likely intense seismic activity, deformation and pressure changes in boreholes.
• It is also possible that magma propagation will not occur, but that the flow of the current eruption will stop decreasing and begin to increase steadily until a new equilibrium between the inflow of magma from below and flow to the surface from the crater is reached.
• However, if magma propagation results in a new eruptive fissure opening elsewhere than in the area between Stóra-Skógfell and Hagafell, such a scenario would very likely be accompanied by intense seismicity and deformation with considerably more notice than previous eruptions.

Updated hazard assessment

In view of the uncertainty caused by increasing pressure in the magma reservoir beneath Svartsengi, the Icelandic Meteorological Office has increased the hazard due to possible opening of eruptive fissures in Zones 1, 4 and 7 from “low” to “considerable”

However, the overall hazard (color) in the affected Zones does not change.

(click on the image to see it larger)

 

Updated 18. April at 16:00 UTC

• The lava field now covers 6.15km² and the volume is 33.2 ± 0.8 million m³.

• Avegage lava flow from the crater over the period 8-15 April is estimated at 3.2 ± 0.2 m³/s.

• Ground uplift in Svartsengi continues at a steady rate.

• Continued hazard due to gas pollution. People in the area are advised to check the air quality.

• The weather forecast for gas distribution today (Thursday) is northwesterly wind, 3-8 m/s, carrying gas emissions to the southeast. Follow the gas dispersion forecast here.

 

The eruption at the Sundhnúkur crater row continues and one crater just east of Sundhnúkur remains erupting. The lava field continues to build up nead the craters. The lava also flows in closed channels about 1 km to the southeast and there are active areas in the lava field north of Hagafell.

On Monday 15 April, scientists from the Icelandic Institute of Natural History (IINH) and the National Land Survey of Iceland (NLSI) carried out a surrveillance flight over the eruptive area to aquire images for lava mapping by photo-grammetry. The results from the surrveilance flight show that the area of the lava field on the 15 April measured 6.15 km² and the volume 33.2 ± 0.8 million m³. The lava flow field and the thickness of it is shown on the map below.

Map showing the lava flow area and the thickness of the lava formed in the ongoing eruption. Purple colors show lava formed in the area since December 2023.

The average lava flow from the crater during the period 8-15 April is estimated at 3.2 ± 0.2 m³/s. This is a small change in relation to the average lava flow during the period 3-8 April, which was estimated at 3.6 ± 0.7 m³/s. The result of previous measurement by the IINH and NLSI photogrammetry team can be seen in the table below.

From	To	Average lava flow during period (m3/s)	Area   (km2)	Volume (million m3)	Average thickness of lava field (m)
16. mar.2024	17. mar.2024	234 ± 9	5,72	18,1 ± 0,8	3,2 ± 0,1
17. mar.2024	20. mar.2024	14,5 ± 0,6	5,58	20,9 ± 0,5	3,7 ± 0,1
20. mar.2024	27. mar.2024	7,8 ± 0,7	5,99	25,7 ± 1,9	4,3 ± 0,3
27. mar.2024	3. apr.2024	6,6 ± 0,3	6,13	29,7 ± 1,7	4,8 ± 0,3
3. apr.2024	8. apr.2024	3,6 ± 0,7	6,14	31,3 ± 2,4	5,1 ± 0,4
8. apr.2024	15. apr.2024	3,2 ± 0,2	6,15	33,2 ± 0,8	5,4 ± 0,1

 

 

Ground uplift in Svartsengi continues at a steady rate. This indicates that about half of the magma ascending from depth is accumulating in the magma reservoir, while the other half erupts to the surface at the Sundhnúkur crater row.

Displacements on the GPS station SENG in Svartsengi since 11 November 2024 to north, east  and vertical (top, middle, bottom). The bottom curve shows ground uplift in millimeters, and yesterday‘s (17 April) measurement is shown with a green dot. The red vertical lines are the timing of the last four eruptions (18 December 2023, 14 January, 8 February and 16 March 2024) and the blue lines show the magma dike intrusions that have occurred in the Sundhnúkur crater row area without resulting in an eruption (10 November 2023 and 2 March 2024).

 

There continues to be a hazard due to gas emissions from the eruption, which can cause pollution in settlements in the Reykjanes Peninsula, and we advise people in the area to monitor air quality and familiarise themselves with the response to air pollution from eruptions.

The weather forecast for gas distribution today (Thursday) is northwesterly wind, 3-8 m/s, carrying gas emissions to the southeast. Tomorrow (Friday) winds will be southeast 8-13 m/s with rain. More southerly winds in the evening. Gas pollution will go to the northwest during the day and later to the north. Follow the gas dispersion forecast here.

 

Updated April 16 at 18:00 UTC

• The hazard assessment has been updated. The overall hazard for Grindavík (Zone 4) is estimated to be considerable (orange).
• Land uplift at Svartsengi continues, and the rate of uplift has been consistent since the beginning of April.
• Continued hazard due to gas pollution. People in the area are advised to check the air quality.
• The gas dispersion forecast can be found here.
• One crater, located east of Sundhnúkur, remains active.

 

The eruption at Sundhnúkur crater row continues and has now lasted for one month, as was the subject of a news report published earlier today. One crater, which is located just east of Sundhnúkur, continues to erupt. Lava still flows to the south of the crater but does not extend far, so the lava field continues to build up near the crater. There is an active lava field near Hagafell, as can be seen in an image from the Icelandic Meteorological Office‘s webcam located at Þorbjörn.

Image from the Icelandic Meteorological Office’s webcam, taken at 5:10 AM, 16 April. The webcamera is located on top of Þorbjörn and looks east towards the eruption site. The crater is at the center of the image and lava flows from it. In front of the crater is Sundhnúkur, and on the right side of the image is Hagafell and lava flow fronts.

Seismic activity has been relatively calm near the eruption site since the beginning of the eruption until a small earthquake swarm began at Lágafell after noon on April 14. The seismic swarm lasted over 4 hours and has been associated with stress changes in the crust due to land uplift in Svartsengi. Seismic activity persists in the western slopes of Fagradalsfjall at 6-8 km depth and has been ongoing since the unrest in the Sundhnúkur area during the past 4 months.

Land uplift continues and has been at a steady rate since the beginning of April. Model calculations based on GPS data indicate that the inflow of magma into the magma reservoir is about half of what it was prior to the beginning of the eruption on March 16. This indicates that about half of the magma coming from depth is accumulating in the magma reservoir, while the other half is erupted to the surface.

At the beginning of April, the rate of land uplift started to increase. Currently, a similar volume of magma is erupting onto the surface and also accumulating in the magma chamber beneath Svartsengi, causing a pressure increase in the magma chamber.

There continues to be a risk of gas emissions from the eruption, which can cause air pollution in settlements on the Reykjanes Peninsula, and we advise people in the area to monitor air quality and familiarize themselves with symptoms and responses related to air pollution from the eruption.

The weather forecast today (Tuesday) is a slow wind, variable direction. Thus, gas may accumulate near the eruption site. Tonight, winds will be southeasterly 10-15 m/s, carrying gas emissions northwest towards Reykjanesbær. West and northwesterly winds are expected to be 3-10 m/s tomorrow morning, dispersing gas east and southeast towards Þorlákshöfn. Follow the gas dispersion forecast here.

Hazard assessment

The hazards assessment has been updated and is valid from 15:00 today until 23 April barring any developments. The hazards assessment has changed so that the hazard due to lava flows has been lowered in all areas except in Zone 3 (Sundhnúkur crater row) and Zone 6. This change is being made because there has not been an active lava flow in the other areas in the last two weeks. Based on current activity in the eruption, it is estimated that lava is unlikely to flow far from the crater and into other hazard Zones. This change means that the overall hazard in Zone 4 (Grindavík) is now assessed as considerable (orange) instead of high (red). The overall hazard in other areas remains unchanged. The hazard from gas emissions continues to be assessed as high in all areas except at the Sundhnúkur crater row area (Zone 3) where it is assessed to be very high. The hazard in Zone 4 (Grindavík) and Zone 6 continues to be assessed as high due to sinkholes and fault movements.

(Click on the image to see it larger)

 

Updated April 15 at 17:30 UTC

• The volcanic eruption that began on March 16 is still ongoing.

• Uplift continues at a similar rate since the start of April.

• The hazard assessment is valid until April 16, unless the situation changes.

• The risk of gas emissions remains significant. People in the area are reminded to monitor air quality.

• The gas dispersion forecast can be found here

 

Just after noon yesterday, a small earthquake swarm began near Lágafell, just northwest of Grindavík. It concluded around half past three in the afternoon. The swarm consisted of approximately 90 earthquakes, with the most intense period of activity being 35 earthquakes between 1 and 2 pm. All earthquakes were under magnitude 1, and most were at depths of approximately 2-4 km. This small earthquake swarm likely resulted from stress changes in the Earth’s crust due to ongoing land rise in Svartengi, as discussed in yesterday’s news update.

Attached is a figure showing the location of the earthquakes on a map, and below that is a graph showing their depth. The panel in the top right displays earthquake magnitudes in the region from noon until evening yesterday. The panel in the middle right shows the cumulative number of earthquakes, while the bottom panel displays the number of earthquakes per hour. As the graph shows, several small earthquakes were recorded in the area yesterday afternoon, but there hasn’t been any seismic activity in the region since midnight today.

Photograph taken on Wednesday, April 10, showing the active vent as seen from Sundhnúkur. (Photograph: Jón Bjarni Friðriksson/Icelandic Meteorological Office). Click on the image to see it larger.

 

Updated April 14 at 18:00 UTC

• The volcanic eruption that began on March 16 is still ongoing.

• Uplift continues at a similar rate since the start of April.

• The hazard assessment is valid until April 16, unless the situation changes.

• The risk of gas emissions remains significant. People in the area are reminded to monitor air quality.

• The gas dispersion forecast can be found here.

 

Several small earthquakes (below magnitude 1) have been detected northwest of Grindavík in the last few hours. (See figures below.) This seismic activity is focused near the dike that formed on November 10 and is likely related to the ground deformation in Svartsengi, which affects the region’s pressure regime.

Today’s seismic activity is comparable to the activity measured in this area in mid-March last year. Therefore, the seismic activity does not indicate any changes in the ongoing volcanic eruption, which has remained relatively stable over the weekend. The seismic activity northwest of Grindavík is also not indicative of magma moving beneath that area.

At the time of writing, the seismic activity northwest of Grindavík has slightly decreased. It is unlikely that large earthquakes will accompany this current activity.

Should magma deviate from its current route that surfaces at the Sundhnúkur crater row, opting instead for an alternate path, such as heading west towards Eldvörp or south of Þorbirnir, the precursor to a possible eruption in that area would involve very intense seismic activity and ground deformation that is clearly visible on instruments and satellite imagery. Currently, there are no such signs at this time.

The Icelandic Meteorological Office continues its 24-hour surveillance of the area to monitor the eruption site.

This figure displays seismic activity from March 9 until today, April 14. The black lines represent the outer boundaries of the grabens formed in connection with the significant dike intrusion on November 10, 2023, and the eruption on January 14 of this year. Most of the earthquakes today have been smaller than magnitude 1. Blue circles represent earthquakes that occurred from March 9 to 14, while red circles represent earthquakes that occurred today, April 14. The earthquakes are located on the western edge of the depression formed on November 10.

In the area northwest of Grindavík, there is a series of known faults with a north-south orientation that formed when the dike intrusion occurred on November 10. Therefore, today’s earthquakes are also indicative of stress release along these faults due to the land uplift in Svartsengi.

 

Updated April 12 at 14:15 UTC

• The volcanic eruption that began on March 16 is still ongoing.
• Land rise continues at a similar rate since the start of April.
• The hazard assessment is valid until April 16, unless the situation changes.
• The risk of gas emissions remains significant. People in the area are reminded to monitor air quality.
• The gas dispersion forecast can be found here .

The eruption that started at the Sundhnúkur crater row on the evening of March 16 is still ongoing. One vent remains active, as it has been since April 5. Lava continues to flow southward from the vent but does not travel far, so the lava field continues to build up near the crater. There are no apparent signs of lava advancing towards the protective barriers north of Grindavík, Suðurstrandarvegur, or Melhólsnáma.

Land rise in Svartsengi continues at a similar rate, which increased at the beginning of April. This is a faster rate than that observed from the start of the eruption on March 16 until the end of March. This indicates that the majority of the magma flowing into the reservoir beneath Svartsengi is accumulating there, causing an increase in pressure and ground uplift. While the eruption continues, there remains an open connection between the magma accumulation area in Svartsengi and the Sundhnúkur crater row, and a portion of the magma continues to flow to the surface there. Minor changes in the lava field can be observed between days, but the overall rate has been steady since the beginning of April.

The hazard assessment remains unchanged and valid until 15:00 on April 16. See more details here.

There is still a risk of gas emissions from the volcano, which could cause pollution on the Reykjanes Peninsula. People in the area are advised to monitor air quality and familiarize themselves with symptoms of exposure to volcanic gas pollution.

A photograph taken on Wednesday, April 10th, showing the active crater as seen from Sundhnúkur. (Photo: Jón Bjarni Friðriksson)

Updated 9. April at 17:30 UTC

• Despite a decrease in the intensity of the volcanic eruption, there are no signs that the overall magma flow from the depth is decreasing.

• The average flow rate of the lava flow from the vents between April 3rd and 8th is estimated to be 3.6 ± 0.7 m3/s.

• Tomorrow, easterly and southeasterly winds are expected, carrying gas emissions westward and northwestward from the eruption sites. Follow the gas dispersion forecast here.

• Periodically high levels of SO2 continue to be measured around the volcano and in settlements on the Reykjanes Peninsula. Residents are advised to monitor air quality in the area.

Experts from the Icelandic Meteorological Office and the National Land Survey conducted aerial measurements over the eruption site yesterday, April 8th. Using the data collected during the flight, it is possible to assess the size of the lava field and the flow rate of lava from the eruption. The results indicate a steady and substantial decrease in the intensity of the volcanic eruption.

The average lava flow from the vents between April 3rd and 8th is estimated to be 3.6 ± 0.7 m3/s. Based on data collected by the engineering firm Efla on April 3rd during a drone flight, the average lava flow was estimated to be 6.6 ± 0.3 m3/s from March 27th to April 3rd. The lava field has reached an area of 6.14 km2 with a volume of 31.3 million m3. Previously, the lava primarily flowed south from the vents, but briefly shifted northward on Sunday evening (April 7th) when a vent wall collapsed, as mentioned in the last update. As shown on the accompanying map, the lava has thickened significantly near the vents and just south of them, where the most activity is in the lava field. There are no apparent signs of lava advancement toward protective barriers north of Grindavík, Suðurstrandarvegur, or Melhólsnáma.

Map showing the extent and thickness of the lava formed in the current eruption. Purple areas show lava that has flowed in the area since December 2023.

Ground deformation has increased over the past week

Ground deformation in Svartsengi continues to increase, coinciding with a decrease in the intensity of the volcanic eruption. This indicates that the majority of the magma flowing into the reservoir beneath Svartsengi is accumulating there, causing an increase in pressure and ground uplift. While the eruption continues, there remains an open connection between the magma accumulation area in Svartsengi and the Sundhnúkur crater row, and a portion of the magma continues to flow to the surface there.

Seismic activity in the dike near Grindavík has remained very low and is focused between Sýlingarfell and Stóra-Skógafell, with slight seismicity in western Grindavík. Seismic activity near Fagradalsfjall, which has been persistent for the past month, is ongoing and remains localized at depths of about 6-7 km.

Gas measurements conducted yesterday, April 8th, estimate a sulfur dioxide (SO2) emission rate of 10-18 kg/s from the vents. Periodically high levels of SO2 continue to be measured around the volcano and in settlements on the Reykjanes Peninsula. Gas emissions from the eruption will likely cause pollution on the Reykjanes Peninsula, and residents are advised to monitor air quality and familiarize themselves with symptoms related to air pollution from the eruption.

According to the weather forecast, northerly winds are expected today, carrying gas emissions southward. Slow variable winds in the afternoon may result in gas pollution near the eruption sites. Easterly and southeasterly winds are expected tomorrow, carrying gas emissions westward and northwestward. Follow the gas dispersion forecast here.

Unchanged risk assessment

The hazard assessment has been updated and is valid from 15:00 today until April 16th, unless the situation changes. There are no changes in the hazard assessment, and the risk of gas pollution remains high in all areas except around the Sundhnúkur crater row (Zone 3), where it is assessed to be very high. The risk in Zone 4 (Grindavík) and Zone 6 remains high due to earthquakes, ground deformation, lava flows, and gas pollution.

(Click on the image to see it larger)

Despite the decrease in the intensity of the volcanic eruption, there are no signs that the overall magma flow from depth into the Svartsengi reservoir is decreasing. This refers to the total volume of magma accumulating under Svartsengi, in addition to the magma flowing towards the surface in the current eruption at the Sundhnúkur crater row. It is difficult to predict when this eruption will end; it could continue for a longer period with steady flow or cease in the near future. As magma continues to accumulate under Svartsengi and pressure rises, a possibility remains that the eruption’s intensity may increase again, similar to the events at Fagradalsfjall in 2021. If the eruption ceases soon, magma accumulation will likely continue under Svartsengi, and a sequence of events similar to that observed in the past month may repeat.

Updated 8. April at 16:30 UTC

• The volcanic eruption continues. One vent is active.
• The land has risen in Svartsengi approximately 2-3 cm between April 2nd and 7th.
• Minimal gas emissions were measured over the weekend, but periodically high levels of sulfur dioxide can still be detected around the volcano and in settlements on the Reykjanes Peninsula. Residents are advised to monitor air quality in the area.
• Today’s weather forecast indicates a northeasterly wind direction, causing gas emissions to drift southwestward over areas including Grindavík. Easterly winds are expected tomorrow, April 9th, and gas emissions are anticipated to travel west from the eruption sites. Follow the gas dispersion forecast here.

The eruption at the Sundhnúkur crater row continues, with one vent now active. Yesterday, lava from the vent flowed southward in a constrained stream, resulting in a magnificent river of lava. Meanwhile, the surface level of lava in the crater gradually increased until it was nearly filled. The northern wall of the vent collapsed around 21:30 yesterday evening, causing the lava to flow northward. Today, April 8th, the lava flow has mostly resumed its southward direction. The lava advancing towards the north, as observed yesterday evening and overnight, appears to have halted on the hillside. The crater continues to fill up.

Seismic measurements near the eruption site show volcanic tremor that exhibits strong frequencies between 1 and 2 Hz (green curve on the graph); an increase in the strength of this tremor corresponds with the peak flow of lava from the vent. After the collapse of the vent wall, seismic activity appears to decrease again. Similar seismic activity was observed during the recent Geldingadalur volcanic eruption, during which seismic activity increased as the output of lava intensified.

Uplift has slightly increased in Svartsengi, and based on GPS measurements and synthetic aperture radar images, the land has risen by 2-3 cm from April 2nd to 7th. However, this is less than the ground deformation measured after the previous eruption last month. Increased uplift could indicate that magma flowing into Svartsengi has increased or that there has been a slowdown in the flow of magma towards the current eruption site.

Minimal gas emissions have been detected on gas monitors operated by the Environment Agency of Iceland (UST) and the Icelandic Meteorological Office over the weekend, but periodically high levels of sulfur dioxide can still be detected around the volcano and in settlements on the Reykjanes Peninsula. Residents are reminded to monitor air quality on the UST air quality website loftgæði.is

Today’s weather forecast indicates a northeasterly wind direction, causing gas emissions to drift southwestward over areas including Grindavík. Easterly winds are expected tomorrow, April 9^th, so gas emissions can be anticipated to drift west from the eruption sites. The latest gas dispersion forecast can be followed here.

Updated 4. April at 17:00 UTC

The eruption at the Sundhnúkur crater row continues and two craters are still active as in recent days. The northern crater is larger and most of the lava flow seems to be erupted from it, as can be seen in the image below which was taken last night, 3 April. Lava continues to flow south from the craters on top of the lava field formed in the first few days of this eruption. Last night there no clear signs of lava flow progressing alongside the lava barriers north of Grindavík, Southcoast road or Melhólsnáma mine.

Aerial image from a drone flight operated by Civil Protection last night, 3 April. The image shows the two craters and the lava flowing from them towards the south.

An interferogram covering the period 18 March – 3 April shows that land has risen about 3 cm in Svartsengi during that time. This is considerably slower deformation that was measured prior to the eruptions and dike propagations which have occurred in last months. Data from GPS measurements during the same period suggests that the rate of the land uplift has varied, but it difficult to estimate day-to-day deformation based on this data. Considering the GPS data for the same time period as the interferogram (18March – 3 April), the two datasets are consistent. Land uplift is detected in Svartsengi during the eruption, which has not been seen in the events that have occurred previously on the Sundhnúkur crater row.  This indicates that the system is open, and magma continues to flow from considerable depth below Svartsengi to the surface in the Sundhnúkur crater row. 

Interferogram (InSAR) showing deformation from 18 March – 3 April. Yellow and orange colors show areas around Svartsengi where land uplift is detected.

Gas measurements carried out last Tuesday, 2 April, estimate that approx. 37-41 kg/s of SO₂ is emitted from the craters. Temporary high sulfur dioxide levels continue to be measured around the eruption site and in municipalities in the Reykjanes peninsula. Gas from the eruption is likely to cause pollution in the Reykjanes peninsula and we advise people in the area to monitor air quality at loftgaedi.is and familiarize themselves with the response to air pollution from volcanic eruptions.

The weather forecast today (Thursday) is southeast and southerly winds of 8-13 m/s at the eruption site, causing gas to be dispersed to the northwest and north, meaning gas could be detected in Vogar, Reykjanesbær and Suðurnesjabær. Easterly winds 5-10 m/s tomorrow (Friday), causing gas dispersion towards the west, for example to Svartsengi. Northesterly winds, 5-10 m/s late tomorrow causing gas pollution in the southwest and possibly in Grindavík.

Gas distribution forecast is here.

Hazard assessment published on 2 April remains unchanged and is valid until 9 April barring any developments.

Updated 2. April at 17:30 UTC

• The eruption continues and two craters are now active. Inflation hasn‘t been detected in the last few days.

• Lately, vegetation fires have started around the lava field, and is an ongoing risk while the weather is dry.

• Gas pollution is dispersed to the southwest and later to the west and is likely to be detected occasionally in Grindavík and possibly in Hafnir. Gas distribution forecast and air quality can be monitored.

• Lava margins have reached considerable heights and can be unstable.

• Hazard assessment unchanged.

 

The eruption at the Sundhnúkur crater row continues and two craters are now active. The third crater, which was much smaller than the other two, was extinguished at Easter. Volcanic tremor remains stable.

Inflation in Svartsengi has not been detected in recent days, indicating that less magma accumulates in the magma reservoir beneath Svartsengi, and flows instead towards the craters where it erupts. A balance may be reached between the influx of magma into the Svartsengi reservoir and the eruptive craters, but geochemical surveys might confirm this in the future.

Experts from the National Land Survey of Iceland have processed satellite data from 27 March showing that the lava field was then 5.99 km2 and the volume of lava since the beginning of the eruption was 25.7 ± 1.9 million m3. The average extrusive rate of lava from the craters was estimated at 7.8 ± 0.7 m3/s, which is very comparable to the extrusion rate during the first phase of the Geldingadalir eruption in 2021. The aim is to take aerial photographs of the area in the coming days to get updated extrusion rates since 27 March, which will give further insights into the development of the eruptive activity. The following map shows the lava flow field and its thickness as it was on 27 March.

Map showing the flow field and thickness of the lava formed during the ongoing eruption. Purple layers show lavas that have formed in the area since December 2023.

Vegetation fires around the lava field

Lately, vegetation fires have started around the lava field, and is an ongoing risk while the weather is dry.

Lava margins have reached considerable heights and can be unstable, sudden and rapid lava outbursts can occur if new lobes of lava break out from the edge of a lava margin.

In recent days, high levels of hydrogen sulfide have occasionally been detected in Grindavík. The weather forecast today (Tuesday) is northeasterly and later easterly winds 5-13 m/s at the eruption site. Gas pollution is therefore dispersed to the southwest and later to the west, and is likely to be detected occasionally in Grindavík and possibly in Hafnir. Easterly and southeasterly winds 3-10 m/s tomorrow (Wednesday) causing gas pollution to travel to the west and northwest, and thus could be detected in many parts of the western Reykjanes area, including Reykjanesbær. Gas distribution forecast is here.

Hazard assessment unchanged

The hazard assessment has been updated and is valid from 15:00 today until 9 April, barring any significant developments. There are no changes to the hazard assessment and the hazard from gas pollution continues to be assessed high in all areas except at the Sundhnúkur crater row area (zone 3) where it is assessed as very high. The hazard in zone 4 (Grindavík) and zone 6 continues to be assessed as high due to sinkholes, fault movements, lava flow and gas pollution.

 

Updated 27. March at 14:00 UTC

 

• High levels of SO₂ (Sulfur Dioxide) were measured over the weekend. Gas dispersion forecast can be followed here .
• This concentration of SO₂ is considered very unhealthy. It is important to pay close attention to developments in air quality.
• The volcanic eruption has been stable since Monday, 25. March.
  

 

 

The volcanic eruption has been stable since Monday, 25 March. Eruption tremor has remained consistent since then, as has the activity in the three craters. Lava continues to flow southward from the craters mostly atop the lava field formed during the first days of the eruption. The following image shows the extension of the lava field as extrapolated from satellite images (ICEYE). The latest acquisition was on 26 March and it shows the widening of lava field towards the west, south of Hagafell, as well as further lava advancement towards the east and the south of the active vents.

Striped areas indicate regions where changes occurred in the lava field between March 20 and 26. The red-striped part of the area signifies area where lava had not flowed previously in this eruption. Light purple areas denote areas where lava flowed from eruptions in February and January.

Uplift continues in Svartsengi but at a slower rate than prior to previous eruptions or dike intrusions in recent months. This suggests that magma is still accumulating beneath Svartsengi despite ongoing eruption. Little to no seismic activity has been detected in the area.

 

High levels of SO2 measured past few days

 

Since friday (22 mars) two additional stations to monitor the concentrations of SO2 at the ground have been installed. VÍ, in collaboration with Almannavarnir, located them at Blue Lagoon and in the harbour area in Grindavík. Both stations are streaming data to the UST website, loftgæði.is.

Early yesterday morning, at around 03:00, the station in BL revealed levels of SO2 up to 7000 microgram/m3, and this morning at around 04:00 the station in Grindavík (Nesvegur) measured concentrations up to 9000 micrograms/m3. Such concentrations are considered óholl and people are recommended to follow the instructions provided by UST and Embætti landlæknis (link). On the 26^th March, the station in Hafnir also showed high concentrations of SO2 up to about 2000 microgarm/m3 around midday. The amount of SO2 released by the eruption and the meteorology in the area are still creating the conditions for severe gas pollution in the peninsula.

Photo since this morning (27. March) from IMO’s webcam located at Hópsnes SE of Grindavík. In the center of the photo is Mt. Þorbjörn and the eruption site east of it where the gas plume rises and moves to the west because of easterly winds.

 

Updated 25. March at 16:30 UTC

• High levels of SO₂ (Sulfur Dioxide) were measured over the weekend. Gas dispersion forecast can be followed here .
• This concentration of SO₂ is considered very unhealthy. It is important to pay close attention to developments in air quality.
• Volcanic activity appears to have decreased at Sundhnúksgíga.
• The hazard assessment remains unchanged. Increased hazards persist due to gas emissions

 

Volcanic activity at Sundhnúksgíga appears to have decreased over the past few days. Activity in the vents has decreased and possibly ceased in the smallest craters. Additionally, volcanic tremor has gradually diminished over the past few days. The main lava flow runs southward from the vents and then bends westward. Over the weekend, lava continued to flow into Melhólsnáma and has now filled it. However, the lava also continues to thicken near the craters.

GPS measurements in recent days indicate ongoing land rise in Svartsengi, but it exhibits a slower rate than before. This suggests that magma continues to accumulate in the reservoir beneath Svartsengi despite the ongoing eruption.

High levels of SO2 measured past few days

High levels of SO₂ have been measured in Höfn and Grindavík the past few days. This concentration is considered very unhealthy, and people are likely to experience respiratory symptoms if exposed. It is important to stay indoors, close windows, and turn off air conditioning. This is especially important where outdoor work is being carried out, as stated by the work safety authorities; companies and institutions in the southwest region of the country must pay close attention to further developments in air quality due to the potential risk of gas pollution. People in the area are advised to monitor air quality and familiarize themselves with symptoms of air pollution from volcanic gases.

The weather forecast for today (Monday) predicts northeasterly winds of 3-8 m/s at the eruption sites, with the pollution drifting southwestward (over Grindavík and Svartsengi); gas may accumulate near the eruption sites due to slow wind speeds. In the evening, night, and early morning hours, winds are expected to come from the east at 8-13 m/s at the eruption sites, causing pollution to drift westward, towards areas including Hafnir. During this period, it’s also possible that the wind may become southeasterly at times, potentially causing pollution in Njarðvík, Keflavík, and Sandgerði. By late afternoon tomorrow (Tuesday), winds will shift to be northeasterly at 3-8 m/s, causing the gas pollution to drift southwestward (over Grindavík and Svartsengi) and possibly to accumulate near the eruption sites due to light winds. The gas dispersion forecast can be found here.

No changes in the hazard assessment

The hazard assessment has been updated and is valid from 15:00 today until April 2, barring any significant developments. There are no changes in the hazard assessment, and the risk of gas pollution remains high in all areas except for the Sundhnúksgíga crater row (Area 3), where it is assessed to be very high. The hazard in Area 4 (Grindavík) remains high due to fault movements, sinkholes above fissures, lava flows, and gas pollution.

(Click on the map to see it larger)

 

Updated 22. March at 17:20 UTC

• Updated hazard assessment.
  
• Increased risk due to gas emission. Gas dispersion forecast here
  
• Volcanis activity at the eruption site stable

 

Volcanic activity at the eruption sites near Sundhnúkur remains stable. There is little to no earthquake activity in the dike or its vicinity. Land uplift in the area around Svartsengi has been very slight since the dike intrusion and subsequent eruption began on March 16. This suggests that less magma is accumulating beneath Svartsengi and is instead flowing more directly out of the reservoir through the eruptive fissures. However, there may be indications that uplift has increased in Svartsengi since then, but it cannot be confirmed at this point. Measurements in the coming days will shed more light on this development.

Today’s (Friday’s) weather forecast includes north to northwesterly winds at around 8-15 m/s, shifting to a more northeasterly direction in the evening with somewhat lower speeds, and gentler northeasterly winds tomorrow morning. Gas emissions will mostly be directed south of the eruption sites towards Grindavík. Gas dispersion forecasts can be found here.

Increased hazards due to gas emissions

The hazard assessment has been updated and is valid from 15:00 today, Friday, March 22, until 15:00 on Monday, March 25. The risk due to gas emissions is assessed to be higher within all regions compared to the previous days. This is due to the unfavorable weather forecast for the next few days and higher measured values of sulfur dioxide (SO2) emissions from the eruption sites and the lava field than before. In areas 1 and 5 (northwest of the eruption sites), the risk of lava flows is lower than it was in the past three days. This risk has decreased because the lava flow north of the eruption sites has stabilized, and lava is now preferentially flowing to the south. However, the lava field remains hazardous because it formed very recently.

(Click on the map to view it larger)

 

Updated 21. March at 11:40 UTC

• Average discharge rate for 17 – 20 March is 14.5 m³/s   

• The new lava now covers an area of 5.58 km² and has a volume of 20.9 million cubic meters.

• Accumulation of magma below Svartsengi seems to have stopped and instead magma flows directly to the surface and feeds the eruption.  

• Minor deformation has been measured in the Svartsengi area and in the proximity of the dyke intrusion.

 

The eruptive activity appears to have been relatively stable the last 24 hours. The same vents seem to be active, and craters continue to build up around the vents. Lava flows towards the south from the craters in an active lava stream, both on the surface and below the solidified surface of the lava.

Overview of the eruption site taken on a flight yesterday morning 20 March at 9am. It shows all the active volcanic vents.

Yesterday morning experts from the National Land Survey of Iceland and the Institute of Natural History conducted aerial photography flights over the eruption site. From these images it is estimated that over the period from 17-20 March the average discharge rate of the eruption is 14.5 m3/s. This is similar discharge rate as observed during the eruptions in Fagradalsfjall 2021-2023. However, the discharge rate during the first 24 hours of the eruption was significantly higher. The area of the new lava field was measured 5.58 km2 and the volume 20.9 million cubic meters. The map below shows the extent and thickness of the new lava as measured yesterday morning, 20 March. The lava is 16 m thick where its thickest by the craters.

Map showing the extent of the newly erupted lava. Violet layers show the older lava that erupted in December 2023, January 2024 and February 2024.

Very little deformation has been measured in the Svartsengi area and in proximity of the dyke formation. Any measured deformation is so small that variability between days is inconsiderable. Several more datapoints are needed to infer if any uplift continues in the area. It can though be determined that magma flows now directly to the surface, feeding the eruption.

The weather forecast today for the area is north and north-westerly winds, 8-15 m/s, gas pollution is dispersed to the east and south-east and could be felt in South Iceland, for example in Þorlákshöfn and in Vestmannaeyjar. A more northerly wind tomorrow (Friday), causing gas pollution to be dispersed to the south and south-east and could be felt in and around Grindavík.

 

Updated 20. March at 13:45 UTC

 

The eruptive activity appears to be relatively stable and eruptive vents remain in the same locations as yesterday. Lava flows from the craters towards the south, on top of lava which flowed in the first days of the eruption. Little or no movement has been detected on the lava flow fronts near the South Coast Road and Svartsengi. Seismic activity since the eruption began on Saturday night has been minor.

The weather forecast is increasing south-easterly winds today, 13-20 m/s in the afternoon, but subsides in the evenings. Gas pollution is thus dispersed to the north-west and could be detected in Reykjanesbær and nearby areas. Gas distribution forecast can be found here. On 17 March, SO₂ gas emission from the eruption was measured up to 50 kg/s, but preliminary results from new measurements indicate that the emission of gas has decreased considerably since then.  

An InSAR image published yesterday showed clear signs of land inflation in Svartsengi from 17 to 18 March. GPS data from 18 March suggest that the inflation rate is possibly decreasing. This could be due to magma now flowing towards the surface in the Sundhnúkur crater row and therefore does not accumulate beneath Svartsengi. The development of the eruption and deformation signals over the next few days will reveal whether an equilibrium will be reached between the magma inflow beneath Svartsengi and the lava flow on the surface in the Sundhnúkur crater row.

This morning, experts from the National Land Survey of Iceland and the Institute of Natural History conducted aerial photography flights over the eruption site. From these images it is possible to estimate the size of the lava field and the average lava flow from the eruption. There estimates will be published as soon as the data have been processed.

Figure caption: Overview of the eruption site taken on a flight this morning. It shows all the active volcanic vents and flava flows from them to the south. In the background to the left is Grindavík and to the right is Svartsengi. (Image: Birgir V. Óskarsson – Institute of Natural History).

 

Updated Hazard Map

The Icelandic Meteorological Office has updated its hazard assessment in light of the latest data. The new hazard assessment takes effect today, Wednesday, March 20, and is valid until March 22, unless the situation changes. Zone 3 (the Sundhnúkur crater row), where the eruption is still ongoing, remains unchanged, and the danger is considered very high. The danger in zone 1 (Svartsengi) is now considered considerable, whereas it was previously considered high. The danger in zone 4 (Grindavík) remains high as the risk due to sinkholes, fault movements and lava flow is considered high. In zone 3 (the Sundhnúkur crater row), the risk due to gas pollution is considered very high, but in all other areas, the risk of gas pollution is now considered considerable, whereas it was previously high. This change is due to lower gas emissions from the eruption than at the beginning. The danger due to gas pollution and ash is also assessed based on the weather and dispersion forecast for the next few days, which affects their spread.

(Click on the map to see it larger)

Updated 19. March at 17:30 UTC

• The eruption continues and has been ongoing since 16 March at 20:23 UTC.
• Volcanic tremor is detected and has remained relatively stable for the past two days which indicates that the eruption‘s vigour has not decreased.
• Inflation continues in Svartsengi, suggesting that magma is still ascending from depth into the magma reservoir beneath Svartsengi as well as flowing towards the eruptive site.
• The hazard assessment map which was updated yesterday (18 March) is unchanged.

The eruption continues and has now lasted for over two and a half days, which is longer than the previous three eruptions that have occurred in the area since December 2023. The eruptive activity is in the same places as yesterday afternoon, on the southern part of the volcanic fissure. Crater rims continue to build up and lava fountaining is still considerable. The lava flow front, which was approximately 300 m from the South Coast Road yesterday, does not appear to have moved forward. Lava flow from the craters remains mostly to the south, with active lava flow fronts on top of the lava that flowed at the beginning of the eruption.

Seismic activity has been negligible at the dike area since the eruption started, but volcanic tremor is detected and has remained relatively stable over the past two days, an indication that the eruption’s vigour has not decreased.

When magma propagated from Svartsengi towards the Sundhnúkur crater row on the evening of 16 March, land subsidence was detected in Svartsengi, as when previous magma dike formed. GPS data and satellite images received after the magma propagation show that surface inflation continues in Svartsengi, suggesting that magma is still ascending from depth into the magma reservoir beneath Svartsengi as well as feeding the eruption.

It should be noted that relatively few data points have still been obtained in the short time since the eruption began and that the data is always subject to uncertainty. Deformation data, which will be available in the next few days, will allow experts to further estimate using model calculations the amount of magma flowing in under Svartsengi.

InSAR image showing measured inflation (red areas) between 17 and 18 March after the eruption began. The image is based on data from the ICEYE satellite

According to measurements carried out last night, the outflow of gas from the eruption has decreased compared to what it was at the beginning of the eruption. However, it is still likely that gas pollution will be detected, and the weather forecast indicates increasing south-westerly winds, around 13-20 m/s at the eruption site today, but winds will decrease this evening. Gas pollution is thus directed to the north-east. See gas distribution forecast here.

The hazard assessment map updated yesterday remains unchanged until 15:00 tomorrow 20 March, barring any changes to the situation.

Updataed 18. March at 18:30 UTC

 

The Icelandic Meteorological Office has updated the hazard assessment to account for the latest data. The new hazard assessment takes effect today, Monday, March 18, and is valid until March 20, unless the situation changes. Zone 3 (the Sundhnúkur crater row), where the volcanic eruption is still ongoing, remains unchanged, with the hazard level remaining very high. The hazard level is assessed to remain high in Zone 1 (Svartsengi) due to gas emissions and lava flows. The same applies to Zone 4 (Grindavík), where the danger due to sinkholes above fissures, fault movements, lava flows, and gas emissions is considered high. Zone 5 has been downgraded to considerable risk (orange) and Zone 7 is now downgraded to some risk.

The reason for assessing the danger as greater in Zone 1 than in Zone 5 is the closer distance to the active end of the eruptive fissure. The weather forecast and gas dispersion forecast for the next few days will affect the assessment of gas pollution and ash in the hazard assessment.

 

Updated 18. March at 16:50 UTC

• The volcanic eruption’s activity has been relatively stable since late yesterday.
• There is a very slow movement of the lava flow towards the road Suðurstrandarvegur.
• This morning, the lava flow was approximately 330 meters from the road. The margin has not advanced significantly since yesterday evening.

 

Eruptive activity has been relatively stable since yesterday afternoon. The eruption is focused at two locations along the eruptive fissure, but the northernmost craters that were active yesterday are not active now. The most active areas are near the southern end of eruptive fissure that opened on Saturday evening, with lava flowing from these locations southward towards the road Suðurstrandarvegur. This morning, the lava flow was approximately 330 meters from the road, with minor movement of the margin since yesterday evening. Observations of the area yesterday evening indicate that there is not significant activity or movement of the lava flow that crossed the road Grindavíkurvegur few hours after the eruption started.

 

The extent of the new lava is estimated to be 5.85 square kilometers, based on satellite imagery acquired at 14:56 yesterday, March 17. See the accompanying map. This area estimation, based on satellite data, contains greater uncertainty than calculations based on aerial photographs. If weather conditions allow, an aerial survey of the eruption site will be conducted later today, providing more accurate calculations of the area and volume of lava.

 

The outlines of the lava flow are drawn from satellite images from Iceye. The first image was taken on March 17 at 01:55 (orange color), which is about five and a half hours after the eruption began. The second image was taken at 14:56 on March 17, showing the outlines of the lava, as it was then, shown in red. Purple colors indicate lava flows from previous eruptions.

The weather forecast for later today brings wind from the southeast and east with a speed of 8-13 m/s at the eruption site, followed by decreasing winds from the south and southwest. Gas emissions will therefore drift northwest and west, with a shift to the north later today. Significant uncertainty exists in the strength of gas emissions. Wind from the southwest with a speed of 10-18 m/s is expected tomorrow morning, so the gas emissions will then travel to the northeast. It is unlikely that gas emissions will reach the Capital Region due to strong winds. The gas dispersion forecast can be monitored here.

There is minor seismic activity near the eruption site and throughout the Reykjanes Peninsula. Only a handful of small earthquakes have been observed. The risk assessment will be updated later today.

 

Updated 17. March at 18:40 UTC

 

Since 04:00 UTC today, the propagation of lava has slowed substantially. However, the eruption has not ended, and lava continues to be extruded from a 0.5-km-long fissure, as confirmed by web camera and drone imagery. A lava front extends to the west from Sundhnúkur crater row. This front inundated Grindavíkurvegur in the early hours of Sunday morning at around 00:30 UTC, making the road impassable.

Lava also travelled southwards, and it is now less than 250 m from Suðurstrandarvegur – the main road on the southern coast of the Reykjanes Peninsula. Between 10:15 and 16:30 UTC today, this lava front moved at an average speed of 12 m per hour. Assuming the same speed of movement, it will take the front an additional ~20 hours to reach the main road. In the event of the lava reaching the road, an additional 350 m of propagation would be needed before lava could enter the sea.

Below is a map showing the impact area if the lava were to reach the sea. This scenario and response plans related to it have been discussed at status meetings of the Meteorological Office and Civil Protection yesterday and today.

In the event of lava interacting with seawater, there would be a range of volcanic hazards due to the sudden cooling of lava. Initially, these hazards would comprise localised tephra deposition (solid volcanic particles) and the formation of volcanic gases, principally hydrogen chloride (HCl). Within a radius of 0.5 km from the entry point into the sea, there would be potentially lethal health hazards. With increasing distance, the severity of the volcanic hazards decreases over a radius of 3 km. Beyond that distance, health hazards due to gas pollution would be minor in nature.

Based on the development of the eruption today, our assessment is that lava flow into the sea is an unlikely scenario. However, until the eruption ends, and lava propagation stops entirely, it remains an outcome to consider for hazard assessment purposes. Assuming the same speed of movement (12 m per hour), it would take the southern lava front two days to reach the coastline.

 

Updated 17. March at 13:00 UTC

The volcanic eruption that began at 20:23 last night continues, but during the night the intensity of the eruption decreased, and now there are three active openings on the eruptive fissure. Seismic activity also significantly decreased overnight, with very few earthquakes measured after 3:00, coinciding with a decrease in volcanic tremor. This development is very similar to the three previous eruptions on the Sundhnúkur crater row.

Shortly after midnight, lava flowed over the Grindavík road towards the water distribution pipe from Svartsengi power plant. There has been limited advancement in that lava flow front since this morning and it is now about 200 meters from the pipe. Another lava flow front runs alongside the protective barriers east of Grindavík and towards Suðurstrandarvegur road. Response workers in the area are monitoring the lava’s advance rate, which has been slow and steady since this morning.

The eruption fissure as it was at 11:00 today. To the right of the image is Mt. Stóra-Skógafell, and to the left is Mt. Sýlingarfell. The most active part of the fissure is east of Sýlingarfell, with smaller openings to the north.

Today’s weather forecast is northeast winds of 8-13 m/s with intermittent rain, but the wind will gradually decrease. Gas emissions will mainly drift southwest from the eruption site. Tomorrow, southeast winds of 8-13 m/s are expected with showers, and the gas emissions will likely drift northwest. Temperatures generally range from 1 to 5 degrees Celsius near the eruption sites. There is considerable uncertainty regarding the intensity of gas emissions. See the gas dispersion forecast here.

 

Updated 17. March at 01:25 UTC

 

The Icelandic Met Office has updated the hazard map for the area. Lava flow continues to the south and southeast. The speed of the lava front is estimated to be 1 km/hr.

If the eruption continues at the same rate the scenario of lava reaching the ocean needs to be considered.

Now, about five hours into the eruption, the activity has been fairly constant for the whole length of the fissure.

 

Updated 16. March at 23:50 UTC

 

A volcanic eruption has begun between Mt. Hagafell and Mt. Stóra Skógfell. The eruption began at 20:23 UTC on 16 March, with a 2.9-km-long fissure forming quickly. The length and location of the fissure is similar to the eruption on 8 February 2024.

The pre-eruptive warning phase was very short. The first warning to the Department of Civil Protection and Emergency Management was at 19:43 UTC, and the onset of eruption was confirmed on web cameras just 40 minutes later. The eruption is effusive in nature, so the eruption plume consists mainly of steam and gas.

Picture showing the status of the eruption at 21:40. (Photo: DCPEM/Björn Oddsson)

The Icelandic Coast Guard performed a helicopter flight over the eruption area. The flight had experts from IMO, the University of Iceland, the Department of Civil Protection and Emergency Management. Lava is flowing westwards from the eruption fissure in the direction of Grindavíkurvegur (road) and the protection barriers for the Svartsengi region. Additionally, a large lobe of lava is flowing southeast, towards the protection barriers for Grindavík.

The map shows the fissure opening in red. Orange lines shows lava barriers.

From initial assessments of web camera imagery and aerial photographs from the helicopter flight, the eruption is thought to be the largest (in terms of magma discharge) of the three previous fissure eruptions from the Sundhnúkur crater row. This estimate applies to the first hour of eruptive activity.

At 22:10 UTC, the southern lava front was just 200 m from the barriers on the eastern side of Grindavík and moving at a rate of about 1 km per hour. At 22:20 UTC, lava was 700 to 800 m away from Grindavíkurvegur, nothwest of Grindavík, moving at a rate of approximately 1 km in 1.5 hours.

Updated 15. March at 14:30 UTC

 

Higher uncertainty than before about the timing of the next dike intrusion and possible eruption.

GNSS displacements and recent interferograms show continued inflation of the Svartsengi magma reservoir – at a similar rate to that observed prior to the diking event on 2 March 2024. Geodetic modelling using these datasets confirms the inflation source is also at a similar location and depth as that observed during previous inflation episodes.

The models inditate a recharge volume of approx. 4 million cubic meters to the Svartsengi reservoir since 3 March.

For the diking events that occurred between 14 January to 2 March, the failure limit calculated to trigger these dike intrusions and/or eruptions was consistently estimated at around 10 million cubic meters. This enabled longer-term forecasts to be made based on the volume loss from the magma reservoir during the diking events and then estimating the time window when this amount would be fully recharged, hence triggering the next event.

However, on 2 March it is estimated that a much smaller volume was lost from the magma reservoir during this event (approx. 1.3 million m3) which triggered a small dike intrusion that did not result in an eruption.

A larger volume, compared to the amount lost from the Svartsengi reservoir on the 2 March, has now been recharged, yet a new dike intrusion/eruption has not yet occurred. This indicates a possible change in the magma plumbing system and greater uncertainty in the new failure limit that now needs to be reached, and thus the timing, of the next dike intrusion and/or eruption.

When this new limit is reached, the most likely scenario is another dike intrusion within the existing diking area – between Stóra-Skogfell to Grindavík – which may or may not culminate in an eruption.

Seismicity NW of Grindavík not a sign of dike intrusion there

We cannot rule out the possibility of an eruption occurring within an adjacent area or volcanic system e.g. west of Mt Þorbjörn or in Eldvörp, however, prior to this occurring a new dike will first need to be intruded in the corresponding area.

There is currently no evidence of a dike intrusion within these areas. Such an intrusion in a new area, is expected to be characterised by a strong earthquake sequence, and large amounts of ground deformation detected on both the GNSS network and on interferograms – none of these monitoring datasets currently show any evidence of this.

There has been an increase in seismicity (all earthquakes < M1.5) to the north west of Grindavík. It is likely that the continued inflation of the Svartsengi magma reservoir is now triggering small movements on pre-existing faults in this area that were activated during the 10 November 2023 diking event.

The map shows seismicity detected from 3 March to 14 March. Black lines outline Grabens that formed in diking events on 10 November 2023 and 14 January 2024.

 

Updated 12. March at 17:00 UTC

• The volume of magma beneath Svartsengi continues to increase, which could result in a new dike intrusion and possibly an eruption.
• An eruption could occur with very short notice, possibly less than 30 minutes.
• The most likely eruption site is between Stóra-Skógafell and Hagafell.

 

Model calculations show that magma accumulation at Svartsengi continues at a steady rate. In previous events a magma intrusion has formed when the volume of accumulated magma has reached 8 to 13 million cubic meters. The total volume accumulated now has already reach this threshold. Pressure buildup therefore continues to increase in the magma chamber and likelihood of a new dike intrusion and even an eruption in the next days is increased.

140 earthquakes have been detected in the vicinity of the Sundhnúkur crater row and Grindavík since Friday. The majority of these earthquakes have been minor or below magnitude 1.0 whilst the largest measured event was a M2.8 on Friday evening, at around 5km depth just SE of Þorbjörn. Seismic activity in the area has increased slightly in the past few days compared to last week, which can possibly be linked to calmer winds and optimal weather conditions for earthquake detections.

The IMO has updated the hazard assessment map. The hazard level remains unchanged from the last map. The new hazard assessment map took effect at 15:00 today, Tuesday, March 12th and is valid until March 19th, barring any changes to the situation.

‘

(Click on the image to see it larger)

Unusually rythmic pattern of unrest, upto this point.

As reported last week, the behavior of the dike propagation on March 2nd differed in some ways to the previous dike formations. Scientists will continue to gather data and infer if the event on March 2nd indicates possible changes to the unusually rythmic pattern of unrest with magma accumulation at Svartsengi and repeated dyke intusions and eruptions.

These events of unrest have previously been compared to the unrest in Krafla that started in 1975. During a period of 10 years, 20 magma intrusions occurred with 9 of them culminating in a volcanic eruption (See image below). In the Krafla unrest magma always intruded into the same dike, but at different scales of magnitude. However, the eruptions did not follow a similarly regular pattern as observed so far in the Sundhnúkar crater row and has in fact been unusually rythmic.

The image shows the interaction between magma intrutions and ground uplift in the center of the Krafla caldera. The graph below shows the elevation of measurement point within the Krafla caldera and the graph above shows the distance from the caldera to the dike formations.

 

Updated 7. March at 17:00 UTC

 

Likely sequence of events over the next several days:

 

• The volume of magma beneath Svartsengi continues to increase, which could result in a new dike intrusion and possibly an eruption.
• An eruption could occur with very short notice, possibly less than 30 minutes.
• The most likely eruption site is between Stóra-Skógafell and Hagafell.

 

Seismic activity associated with the volcanic unrest has been decreasing since Saturday, with very few earthquakes detected in the past few days. However, unfavorable weather conditions have disrupted seismic monitoring by dampening small events, so there have likely been additional minor earthquakes that could not be detected.

Weather conditions over the next 24 hours will likely hinder the Meteorological Office’s earthquake monitoring system. The forecast indicates that Reykjanes will experience strong winds from the southeast accompanied by rain and limited visibility, especially in mountainous regions. Precipitation will decrease in the early morning, with occasional showers coinciding with reduced visibility expected tomorrow and the following days.  Winds are expected to decrease over the weekend, coming from the southeast or northwest on Sunday.

Inflation continues at Svartsengi, and model calculations based on GNSS data from March 3rd to 6th indicate that approximately 1.2 million cubic meters of magma has been injected into the magma chamber during these days. Therefore, approximately 10 million cubic meters of magma has accumulated in the magma chamber overall since the last eruption. The current situation is therefore similar to what it was before the eruption on March 2nd.

Updated hazard assessment

The Meteorological Office has updated the hazard assessment map. The hazard level remains unchanged from the last map. One change has been made to the zoning; Zones 2 and 3 have been merged into one single zone. Given the development of the activity, there is no longer a reason to assess the risk in these areas separately. The new hazard assessment map took effect at 3 p.m. today, Thursday, March 7th. This hazard assessment is valid until March 12th, barring any changes to the situation.

 

(Click on the map to see it larger)

Updated 5. March at 14:20 UTC

 

Likely scenarios over the next few days:

• The volume of magma within the Svartsengi reservoir continues to increase, which could result in a new dike propagation and/or volcanic eruption in the coming days.  
• A volcanic eruption could start with a very short warning time, even less than 30 minutes.
• It is most likely that an eruption will occur in the area between Mt. Stóra-Skógfell and Mt. Hagafell. 

 

 

 

Seismicity over the dike has been low since the magma propagation ended on Saturday (2 March) evening. There is slightly more activity at Mt. Fagradalsfjall, where around 20 earthquakes have been detected in the last 24-hours.

Model calculations indicate a volume loss of about -1.3 million cubic metres from the Svartsengi magma reservoir on Saturday – which fed a 3-km long dike intrusion between Mt. Stóra-Skógfell and Mt. Hagafell. The volume loss from the Svartsengi reservoir was much lower than that which occurred during previous events, where a volume loss of about -10 million cubic metres was calculated.

Continuous land uplift is detected on GNSS observations since Saturday‘s magma propagation. Magma inflow beneath Svartsengi thus continues and model calculations suggest an inflow/accumulation rate of about half a million cubic metres per day. In total, about 9,5 million cubic metres of magma has been recharged to the reservoir beneath Svartsengi since the eruption on 8-9 February. 

Therefore, pressure in the magma reservoir continues to build up, and there is an increased likelihood of another dike propagation within the Sundhnúkur crater row and/or a volcanic eruption in the coming days.

 

 

The graph shows a comparison of volume increase within the Svartsengi reservoir prior to dike propagations and/or eruptions. The status of the volume change as of 4 March is indicated by the red line. This line also shows what affect the magma propagation on the 2 March had on the accumulation process within the magma reservoir beneath Svartsengi. The quantities displayed on this graph are derived from model calculations based on GNSS data alone. Joint InSAR-GNSS modelling of the diking event on Saturday indicates a volume loss of about -1.3 million cubic metres from the Svartsengi reservoir which fed the dike propagation within the Sundhnúkur crater row, without resulting in an eruption. Values derived from both the GNSS only and the joint InSAR-GNSS inversions are subject to uncertainty.

 

Weather conditions might affect IMO‘s monitoring systems.

 

The Icelandic Meteorological Office has updated the hazard assessment map, which is unchanged from the previous hazard assessment. The new hazard assessment is valid until Thursday, 7 March, unless developments in activity call for a re-evaluation.

 

 

The weather over the next few days is likely to affect the monitoring systems. The forecast for the week is southeasterly and easterly winds, around 10-15 m/s. Rain showers most days with increasing windspeeds and more calmer winds in between showers.

 

 

Updated 4. March at 16:00 UTC

 

Likely scenarios over the next few days:

• The volume of magma beneath Svartsengi continues to increase, which could result in a magma propagation and even a volcanic eruption.
• A volcanic eruption could start with a very short warning time, even less than 30 minutes.
• It is most likely that an eruption will occur in the area between mt. Stóra- Skógfell and mt. Hagafell.

Model calculations suggest that the volume of magma which propagated from Svartsengi to the Sundhnúkur crater row was around 1.3 million cubic metres.

It had previously been calculated that about 0.5 million cubic metres of magma accumulates beneath Svartsengi each day. Considering this, the total amount of magma beneath Svartsengi will be around 9 million cubic metres by the end of tomorrow, Tuesday 5 March.

In previous events, magma has propagated once the total volume of magma accumulated beneath Svartsengi reaches between 8-13 million cubic metres. Therefore, there is an increased likelihood of new magma propagation and volcanic eruption once these conditions are met.

However, it should be noted also, that after repeated eruptions in mt. Fagradalsfjall, there were examples of magma reaching slowly to the surface without much seismic activity. This sort of development should also be expected on the Sundhnúkur crater row.

 

Updated 3. March at 12:15 UTC

 

Likely scenario over the next few days

 

• Magma volume beneath Svartsengi continues to increase, which could lead to another magma propagation and even a volcanic eruption.
• A volcanic eruption could start with a very short warning time, event less than 30 minutes.
• A volcanic eruption is most likely to occur in the area between mt. Stóra-Skógfell and mt. Hagafell.

 

The Icelandic Meteorological Office has updated the hazard assessment map due to the decrease in seismic activity in the Reykjanes peninsula.

Considering the developments in activity since yesterday, the hazard level has been lowered in two zones – Zones 2 and 3. The hazard level remains unchanged in other areas, thus the hazard assessment is now the same as it was prior to yesterday‘s event.

The hazard assessment map is valid from 13:00 UTC today, 3 March, until 15:00 Tuesday 5 March unless development in activity call for a re-evaluation.

 

(Click on the map to see it larger)

Updated 3. March at 11:50 UTC

 

Seismic activity at mt. Sýlingarfell was due to a magma intrusion. The seismic activity started around 16:00 UTC yesterday (2 March) and subsided steadily after 18:00 and after 20:00 it was mostly over.

Data indicate that yesterday‘s magma intrusion has stopped by mt. Hagafell. The likelihood of magma ascending in relation to this magma intrusion has decreased but the area continues to be closely monitored for this possibility.

Model calculations indicate that the volume of magma that propagated out of Svartsengi yesterday was negligible comparted to previous magma propagations which culminated with an eruption.

Therefore, it can be assumed that magma accumulation beneath Svartsengi is continuing as before and that the volume of magma which has already been accumulated suffices to trigger another magma propagation. It can be expected that another magma propagation can occur in the next few days and there continues to be an increased likelihood of an eruption, as before yesterday‘s event.

This depends on how quickly the pressure caused by magma accumulation under Svartsengi builds up to trigger another magma propagation. 

Considering these developments, The Icelandic Meteorological Office is working on a new hazard assessment map which will be updated in the coming hours.

Likely scenarios over the next few days:

 

• Magma volume beneath Svartsengi continues to increase, which could lead to another magma propagation and even a volcanic eruption.
• A volcanic eruption could start with a very short warning time, event less than 30 minutes.
• A volcanic eruption is most likely to occur in the area between mt. Stóra-Skógfell and mt. Hagafell.

The graph shows a comparison of volume of magma accumulated beneath Svartsengi before it propagates towards Sundhnúkur crater row. The status of the magma volume at 2. March after the magma propagation er indicated with red colour. The amount is derived through model calculations based on GPS data and subject to uncertainties. Changes can vary from day to day, from being small to more prominent changes. The purple line shows the magma volume accumulated prior to the large diking event beneath Grindavík formed on the 10^th of November 2023. 

Updated 2. March at 19:10 UTC

 

At this point, the seismicity that began just before 16:00 UTC today has ceased. It is thus considered likely that the magma intrusion has stopped temporarily or is significantly diminished. However, minor deformation continues to be measured in the area, so it is too early to assert that the magma intrusion has ended, and that there will not be an eruption at this time. When magma intrusions occur, deformation can be measured for several hours after the seismic activity stops.

The Icelandic Meteorological Office continues to monitor the area to observe whether the activity resumes in the next few hours, or if the magma intrusion has halted completely. It remains possible that magma could ascend to the surface, as has been observed in eruptions near Fagradalsfjall.

 

Updated 2. March at 17:30 UTC

• An intense swarm of microseismic activity is occurring east of Sýlingarfell on the Reykjanes Peninsula.
• The seismicity indicates that magma movements have begun, and that a fissure eruption is likely.
• The seismicity began at the southern end of the fissure that formed on 18 December 2023.

• As of 17:30 UTC, it is apparent that the seismic activity has moved southwards in the direction of Hagafell.

• Real-time, GPS-based measurements show much less signs of deformation than before previous eruptions since December 2023. This could signify that less magma is on the move than before the previous three eruptions on Sundhnúkur crater row.
• At present, the depth of the seismicity does not indicate that magma is propagating to the surface.
• As of 17:30 UTC, the likely scenario is that the magma intrusion will not necessarily lead to a volcanic eruption. However, while the situation remains uncertain, a imminent fissure eruption cannot be ruled out.

A new hazard assessment map from IMO was published today and is valid until tomorrow (3. March 2024) at 17:00 UTC

Updated 29. February at 12:30 UTC

• An eruption could start with very little warning time, even less than 30 minutes.  
• Eruption location is most likely in the area between Mt. Stóra-Skógfell and Mt. Hagafell.  
• The hazard assessment does not account for weather conditions or other factors that may affect the risk of being within the hazard zones.
• It is possible that a dike intrusion occurs without resulting in a volcanic eruption.

 

Model calculations suggest that as of today, about 8.5-9 million cubic metres of magma has accumulated beneath Svartsengi. The rate of the inflation has been fairly constant for the past days. In previous developments, the rate of inflation has decreased shortly before an eruption starts.

According to model calculations, approximately 0.5 million cubic metres of magma is accumulated in the Svartsengi reservoir every 24 hours.

Considering precursors of previous volcanic eruption in the Sundhnúkar crater row, likelihood of a volcanic eruption increases once the volume of magma reaches 8 – 13 million cubic metres. If magma accumulation continues at the same rate, the amount should reach the upper limit next week.

There remains an increased likelihood of a volcanic eruption in the coming days. The most likely scenario is that a volcanic fissure opens in the area between mt. Stóra-Skógfell and Mt. Hagafell which could occur with a very short warning time.

The graph shows a comparison of volume of magma accumulated beneath Svartsengi before it propagates towards Sundhnúkur crater row. The status of the magma volume at 28^th of February is indicated with red colour. The amount is derived through model calculations based on GPS data and subject to uncertainties. Changes can vary from day to day, from being small to more prominent changes. The purple line shows the magma volume accumulated prior to the large diking event beneath Grindavík formed on the 10^th of November 2023. 

A new hazard assessment map from IMO was published today and remains unchanged from the previous one. The hazard assessment map is valid until 5^th of March unless developments in activity call for a re-evaluation. Likely scenarios presented earlier this week also remain unchanged (see news from 26^th of February).

Please note that although IMO has at this point not increased hazard level on the unrest area, developments can occur very quickly and without warning. People entering the unrest area need to keep this in mind. The hazard assessment by IMO does not account for weather conditions or other factors which may affect the risk involved when being within a hazardous area.

 

Updated 27. February at 13:00 UTC

• Accumulated magma beneath Svartsengi reaching same amount as prior to previous eruptions.
• An eruption could start with very little warning time, even less than 30 minutes.
• Raised hazard levels in an updated hazard assessment due to impending eruption.
• Eruption location is most likely in the area between Mt. Stóra-Skógfell and Mt. Hagafell.
• The hazard assessment does not account for weather conditions or other factors that may affect the risk of being within the hazard zones.
• It is possible that a dike intrusion occurs without resulting in a volcanic eruption

 

Model calculations suggest that about 7.6 million m³ of magma has been recharged within the Svartsengi reservoir. Considering precursors of previous volcanic eruption in the Sundhnúkar crater row, likelihood of a volcanic eruption increases once the volume of magma reaches 8 – 13 million m³. If magma accumulation continues at the same rate, the amount should reach the lower limit tomorrow (27^th of February).

Seismic activity has increased slightly since past weekend and has been most prominent just east of Mt. Sýlingarfell. The location of the seismic activity is in an area which is considered to be the eastern tip of the magma reservoir which is centered beneath the Svartsengi-Þórbjörn area.  The current seismicity is similar to that observed days before previous volcanic eruptions in the area.

Therefore, IMO has updated the hazard assessment for the unrest area. Increased likelihood of a volcanic eruption and related hazards affects the assessment. Hazard levels have been raised in several zones. Even though the color of Zone 4 – Grindavík – remains unchanged, the hazards there have increased due to the possibility of lava flows. Same goes for Zone 1 – Svartsengi.

No significant deformation within Grindavík has been detected by GNSS or satellite data. It is however likely that new faults will be revealed when snow melts or precipitation causes soil, which might be covering faults, to be washed away.

 

 

Likely scenarios

If an eruption occurs, scientists estimate that magma will most likely propagate from the reservoir beneath the Svartsengi-Þórbjörn region towards Sundhnúkur crater row, resulting in lava fountaining and lava flows in the area between Stóra-Skógfell and Hagafell. The primary signal of ascending magma is a sudden increase in seismic activity with many localized, small magnitude earthquakes. Considering the previous volcanic eruptions in the area, an eruption could start with very little warning (less than 30 minutes), depending on where magma reaches the surface on the Sundhnúkur crater row. 

 

 

At a community meeting held today with residents of Grindavík, IMO presented results from lava flow models, showing scenarios considered to be likely and which were explained before last weekend.

The modelled results presented showed estimated lava flow from two separate eruptive fissures located on the Sundhnúkur crater row. The lava flow models do not forecast the behaviour of the next volcanic eruption. The models are only used to predict possible lava flow pathways from different locations of eruptive fissures.

Many factors affect a lava flow: location and length of the eruptive fissure, volume of erupted material, topography of the land surface and whether craters or lava lobes form.

These modelled scenarios predict lava flowing from an 800 m long eruptive fissure with a constant extrusion rate of 600 m3/s.  The fissures are shown on the maps as black lines.

These modelled results below are therefore only 2 examples for the Sundhnúkar crater row, but the behaviour of the lava flow in the next volcanic eruption can be very different depending on where exactly a fissure opens on the surface and how long it will be. A minor shift in location can significantly alter the lava flow pathway.

 

 

Eruption between Sýlingarfell and Stóra-Skógfell – As occurred on December 18, 2023 and February 8, 2024. 

• Precursor: Sudden, localized, and intense seismic activity with small magnitude earthquakes. Deformation over the magma dike (if a dike is intruded) and the Svartsengi magma reservoir 
• Very short warning time (less than 30 minutes) because a new dike propagation may not be required for magma to reach the surface. 
• Lava reaches Grindavík road within 2 to 4 hours, but possibly less, if the velocity of the advancing lava front is higher than that observed during previous eruptions

The modelled results presented showed estimated lava flow from a fissure just south of Stóra-Skógfell. The lava flow models do not forecast the behaviour of the next volcanic eruption. The models are only used to predict possible lava flow pathways from different locations of eruptive fissures. The velocity of the advancing lava front can also be higher than that shown in the model.

 

Eruption by Hagafell – As occurred on January 14, 2024.

 

• Precursor: Seismic activity with small magnitude earthquakes on the Sundhnúkur crater row, starting near Sýlingarfell and migrating south. Deformation over the magma dike and the Svartsengi magma reservoir
• Likely warning time is approximately 1-3 hours from the detection of the first earthquakes until the start of an eruption.
• Lava reaches the lava barriers around Grindavík within 1 hour.
• Magma intrusion, which reaches south of Hagafell, will likely cause significant fault movements in Grindavík

The modelled results presented showed estimated lava flow from a fissure west of Hagafell. The lava flow models do not forecast the behaviour of the next volcanic eruption. The models are only used to predict possible lava flow pathways from different locations of eruptive fissures. The velocity of the advancing lava front can also be higher than that shown in the model.

 

Eruption inside of the lava barriers around Grindavík

 

• Seismic activity with small magnitude earthquakes on the Sundhnúkur crater row, starting near Sýlingarfell and migrating south. Deformation over the magma dike and the Svartsengi magma reservoir
• Probable warning time is between approximately 1-5 hours from the detection of the first earthquakes until the start of an eruption.
• It is possible that an eruptive fissure/s will open within Grindavík or the region just north of here (inside the barriers). Similar activity occurred on the 14^th of January when a volcanic fissure opened just inside the outer perimeter of the town approximately 4 hours after an onset of the eruption near Hagafell.
• Magma intrusion, which reaches south of Grindavík, will cause significant fault movements in Grindavík.

The Icelandic Meteorological Office and the University of Iceland have compiled material that describes the Volcano-tectonic reactivation of the Reykjanes Peninsula since 2019. See here .

 

Updated 23. February at 15:00 UTC

 

Model calculations indicate that approximately 5 million cubic meters of magma had recharged to the Svartsengi reservoir as of the 22 February. Considering the trend observed prior to previous volcanic eruptions in the Sundhnúkur crater row, the likelihood of an eruption is very high once the volume reaches between 8-13 million cubic meters (derived from joint InSAR-GNSS models). Based on the results of the model calculations, this could occur early next week if magma accumulation continues at the current rate.

It should be noted that there is a degree of uncertainty in this interpretation, and it cannot be assumed that the behaviour will be identical to the past eruptions here. Also, as the magma plumbing system evolves, we cannot rule out the possibility that the volume of magma required to trigger a new diking event and/or eruption may become reduced.

Additionally, there is a possibility a new dike intrusion occurs within this region without resulting in a volcanic eruption.

 

 

 

 

 

Figure: The graph displays a comparison of the volume of magma accumulated beneath Svartsengi before the magma flowed towards the Sundhnúkur crater row during the recent dike intrusions and eruptions that occurred between December 2023-February 2024. The volume is calculated by a model based on GNSS data and is subject to uncertainty. Significant variations can also be observed between consecutive days. The current magma accumulation status as of February 22 is marked by the purple line. The red line shows the amount of magma accumulated before the major diking event beneath Grindavík on November 10th.

 

 

 

If an eruption occurs, scientists estimate that magma will most likely propagate from the reservoir beneath Svartsengi towards Sundhnúkur crater row, resulting in lava fountaining and lava flows in the area between Stóra-Skógfell and Hagafell. The primary signal of ascending magma is a sudden increase in seismic activity with many localized, small magnitude earthquakes. Considering the previous volcanic eruptions in the area, an eruption could start with very little warning (less than 30 minutes), depending on where magma reaches the surface on the Sundhnúkur crater row.

 

Likely scenarios

Eruption between Sýlingarfell and Stóra-Skógfell – As occurred on December 18, 2023 and February 8, 2024.

• Precursor: Sudden, localized, and intense seismic activity with small magnitude earthquakes. Deformation over the magma dike (if a dike is intruded) and the Svartsengi magma reservoir 
• Very short warning time (less than 30 minutes) because a new dike propagation may not be required for magma to reach the surface. 
• Lava reaches Grindavík road in less than 4 hours.

Eruption by Hagafell – As occurred on January 14, 2024.

• Precursor: Seismic activity with small magnitude earthquakes on the Sundhnúkur crater row, starting near Sýlingarfell and migrating south. Deformation over the magma dike and the Svartsengi magma reservoir
• Likely warning time is approximately 1-3 hours from the detection of the first earthquakes until the start of an eruption.
• Lava reaches the lava barriers around Grindavík within 1 hour.
• Magma intrusion, which reaches south of Hagafell, will likely cause significant fault movements in Grindavík

Eruption inside of the lava barriers around Grindavík

• Seismic activity with small magnitude earthquakes on the Sundhnúkur crater row, starting near Sýlingarfell and migrating south. Deformation over the magma dike and the Svartsengi magma reservoir
• Probable warning time is between approximately 1-5 hours from the detection of the first earthquakes until the start of an eruption.
• It is possible that an eruptive fissure/s will open within Grindavík or the region just north of here (inside the barriers). Similar activity occurred on the 14^th of January when a volcanic fissure opened just inside the outer perimeter of the town approximately 4 hours after an onset of the eruption near Hagafell.
• Magma intrusion, which reaches south of Grindavík, will cause significant fault movements in        Grindavík.

 

Although there is clear indication of uplift in the Svartsengi-Þórbjörn area (related to magma recharge of this reservoir) this does not mean that it is the most likely location for an eruption to start. This is because the magma reservoir is currently failing on its northeastern edge feeding dike propagations which are initiated between Stóra-Skógfell- and Sundhnúkur crater row.  In a scenario where magma ascends towards the surface directly from the Svartsengi reservoir, it is estimated that the first signs of magma migration would be detected 4-7 hours before magma reaches the surface.

Please note that these scenarios are based on interpretations of the latest data and the observed development of the previous events at the Sundhnúkur crater row area. Uncertainty must be accounted for in this interpretation, as it is only based on few events.

 

 

Updated 23. February at 9:30 UTC

 

Seismic activity in the unrest area north of Grindavík remains minimal. About 20 small earthquakes have been detected on a 24-hour basis for the past days.

Magma accumulation beneath Svartsengi continues and the pace of the accumulation has been quite steady. This is a similar trend as has been observed prior to the previous volcanic eruptions.

The event which started at the end of October 2023 with an inflation at Svartsengi thus continues. Whilst magma accumulation persists, another volcanic eruption is expected in similar areas as before.

Should magma accumulation continue at current pace, the amount will reach a threshold believed necessary to trigger a dyke propagation and even an eruption, by next week. The amount of magma accumulated beneath Svartsengi before previous eruptions is estimated to have been 8-13 million m³. New model calculations are underway to obtain a better understanding of how much magma has now been accumulated.

At the moment, it is not considered necessary to raise the hazard level in the area and thus the hazard assessment issued by IMO remains unchanged.

The hazard assessment will be updated Monday 26^th of February and should the development continue at similar rate as now, hazard levels in zones will be raised as more magma will be accumulated and thus there is a higher likelihood of an eruption.

(Click on the map to see it larger)

 

Updated 20. February at 11:00 UTC

 

The Icelandic Meteorological Office has issued an updated hazard assessment map following the decision of the National Police Commissioner to repeal the order of a temporary evacuation from Grindavík, taking effect on the 19th of February, and due to the decision of the Police Commissioner in Suðurnes regarding changes in access restrictions for both individuals as well as business operations.

An updated hazard assessment map is valid from 20^th of February at 7AM, which is the same time as the decision of the Police Commissioner in Suðurnes goes into effect.

In the latest version of IMO’s hazard assessment map, Zone 7 has been added in consultation with Civil Protection. Nesvegur road is within Zone 7, which is currently more used to access Svartsengi and Grindavík. Hazards present in Zone 7 are fault movements and sinkholes. Colour code of other areas remain unchanged from previous hazard map.

Read here about the decision of the Police Commissioner in Suðurnes. (Icelandic).

As before, the map shows assessment of hazards currently at hand, as well as hazards which might occur with short notice. An assessment has only been made for hazards within the defined Zones, but hazards can also be present outside of them.

 

Updated 15. February at 16:00 UTC

 

Land uplift at Svartsengi area continues at similar trends and rates as has been detected following dyke propagations from there.

 Model calculations based on GPS data suggest that magma accumulation from the end of the eruption 9^th of February until yesterday, 14^th of February, is about 2 million m³. It was estimated that when the eruption began on the 8^th of February, about 10 million m³ of magma propagated from Svartsengi towards Sundhnúkur crater row. If magma accumulation continues at same rate, a total of 10 million m³ will be accumulated by the end of February or beginning of March, by which time likelihood of dyke propagation and volcanic eruption will increase significantly. These model calculations are based on GPS data but will be updated when new satellite data comes in.

Seismic activity in the western parts of mt. Fagradalsfjall continues with about 80 small earthquakes of magnitudes 1.5 or smaller detected since 12^th of February. The depth of the earthquakes under the western part of mt. Fagradalsfjall is at 6-8 km. The area remains closely monitored but at the moment deformation data do not show signs of magma accumulation.

An updated hazard map has been published. It is valid until 22^nd of February unless developments call for a re-evaluation. The main changes are that likelihood of eruptive vents opening has decreased in all Zones. Likelihood of sinkholes and fault movements are still considered high in Zone 4 (Grindavík). Please note that the hazard zones are active, and changes can occur with short notice. Furthermore, hazards can be present outside of the specified hazard zones, such as the faults that formed on the 10^th of November 2023 west of Grindavík (see faults on map).

(Click on the map to make it larger)

 

Updated 12. February at 16:00 UTC

 

IMO has updated the hazard assessment according to the development of the eruptive activity. Changes have been made to the hazard assessment for some hazards within zones. 

The overall hazard assessment for the area remains unchanged from the last map. There is still considered to be a sinkholes and fault movementsn area 4 (Grindavík).

(Click on the map to make it larger)

The hazard assessment map is valid until Thursday, 15 February, unless changes in activity calls for a re-evaluation.   

 

Updated 12. February at 14:30 UTC

 

Inflation has started again at Svartsengi after having subsided following the eruption which started 8. February. Inflation rate is about 0.5-1.0 cm/day which is in similar to the rates detected prior to last eruptions. Magma thus continues to accumulate in the magma reservoir beneath Svartsengi. It is therefore highly likely that the cycle continues in a few weeks with another dyke propagation and a volcanic eruption.

Time series from the GPS station Svartsengi (SENG) since 11^th of November 2023 in the north, east and vertical directions (top, middle and bottom images, respectively). The bottom time series show land uplift in millimetres and yesterday’s datapoint (11^th of February) is shown with a green dot. The red vertical lines are timings of the last three eruptions (18^th of December 2023, 14^th of January 2024 and 8^th of February 2024).

Since noon of 8. February, seismic activity in the area north of Grindavík has been minor, about 50 small earthquakes have been detected, all of which were around or less than M1.0. A small seismic swarm has been ongoing in the western parts of Mt. Fagradalsfjall with about 100 earthquakes detected, mostly M1 events or smaller. Minor swarms in the Fagradalsfjall area have occurred frequent for the past weeks, the depth of the earthquakes is at around 6-8 km.

 

Updated 9. February at 15:30 UTC

 

No eruptive activity was observed in a drone-flight over the eruptive site carried out at noon today (9 February) by the Special Unit of the National Police Commissioner. This suggests that the eruption is ending. Volcanic tremor is no longer being detected on seismic sensors.

IMO has updated the hazard assessment according to the development of the eruptive activity. Changes have been made to the hazard assessment for some hazards within zones. Hazards due to opening of volcanic fissures has decreased, but hazards due to gas pollution are still considered to be likely by the lava flow front. Hazards due to lava flow is still in place, as lava lobes can burst out from the lava flow front. Hazards due to sinkholes and fault movements are still considered high in Zone 4 (Grindavík).

(Click on the map to see it larger)

The hazard assessment map is valid until 15:00 on Monday, 12 February, unless changes in activity calls for a re-evaluation.   

 

Updated 9. February at 13:00 UTC

 

Volcanic tremor has significantly decreased since yesterday (8th of February). The decrease was detected shortly after noon yesterday alongside decreased eruptive activity on the volcanic fissure and activity became more confined in separate craters. Temporary increases of the volcanic tremor were noted last evening, which coincided with increased volcanic activity in the craters. During the night, the activity decreased further and between 7 and 8 this morning, two eruptive craters were active. For the past hours no lava fountaining has been observed on web-cameras but activity within the craters might still be ongoing.

Satellite radar image taken at 14:56 yesterday shows surface subsidence of 10 cm in Svartsengi area, north-west of mt. Þorbjörn, when magma flowed from there towards Sundhnúkur crater row. Model calculations based on these data suggest that about 10 million m³ of magma has flowed from the magma reservoir beneath Svartsengi towards the eruption site at Sundhnúkur crater row. 

(Click on the Insar Satellite Image to make it larger)

Seismic activity at the eruptive site has been minor during the past 24 hours. About 40 earthquakes have been detected there, all around or smaller than M1.

Volume estimates of the erupted lava from the start of the eruption at 6:02 until 13:00 yesterday (8^th of February) is about 15 million m³, which corresponds to an average extrusion rate of 600 m³/s during the first seven hours (data provided by Icelandic Institute of Natural History and Landmælingar Íslands).

Although the eruption has significantly decreased it is still too early to declare if it has come to an end. IMO maintains a 24-hour watch and keeps a close eye on the area. An updated hazard assessment will be published later today.

 

Updated 8. February at 17:15 UTC

 

The vigor of the eruption continues to decrease. The eruptive activity is currently on two or three locations on the eruptive fissure. The explosive activity which began between 13 and 14 o‘clock is now mostly over, but minor convective clouds rise from some parts the fissure.

Synchronously with the decreasing vigor of the eruption, the deformation signals detected at the dyke area diminished, indicating that magma is no longer ascending under as much pressure as before. Soon after the onset of the eruption, seismic activity decreased significantly and has remained minor thus far. About 20 small earthquakes have been detected over the dyke since 08:00 this morning.

The map shows outlines of the lava flow as it was seen on a satellite image taken at 12:31 today (Thursday 8^th– of February). The satellite image shows that lava flowed furthest about 4.5 km to the west from the eruptive site. For comparison, the lava flow field which formed in the eruption on the 18th of December 2023 is also shown on the map. Today ‘s lava flows partly over the lava flow formed in December 2023.

(Click on the map to make it larger)

IMO has updated the hazard assessment map considering the process of the eruptive activity. Changes have been made to the hazard assessment for some hazards within zones. However, these changes do not influence the overall hazard assessment for the zones. The new lava flow field has also been added to the map. The hazard assessment map is valid until 19:00 tomorrow, Friday 9th of February 2024, unless development in activity calls for a re-evaluation.

 

(Click on the map to make it larger)

Updated 8. February at 14:25 UTC

 

The vigor of the eruption is decreasing. The activity is now mainly on 3 locations on the eruptive fissure which opened this morning. This is not unlike the process observed in the eruption 18th of December 2023, when the activity was confined to a few craters few hours after the onset of the eruption.

A conspicuous, dark plume rises from one part of the eruptive fissure. This is likely due to magma interaction with groundwater which results in a slight explosive activity where white plume of steam mixes with dark volcanic plume.

It seems that tephra does not travel far from the eruptive fissure at the moment. The volcanic plume is dispersed towards south-west.

Photo taken towards north-west. (Photo: Special Unit of the National Police Commissioner).

 

Updated 8. February at 12:20 UTC

 

Geodetic data suggest that deformation has decreased significantly in the dyke area. Therefore, probability of new eruptive fissure openings has decreased. 

IMO has received notifications of tephra fall in Grindavík. 

Tephra is frothy and vesicular material which forms when splashes of lava cool quickly in the air in the lava fountaining activity. This process took place when an eruptive fissure opened this morning (8th of February 2024). Due to the tephras‘ vesicularity and lightness it can be transported far within the volcanic plume with wind. It falls in Grindavík now, 3-5 km from the source of formation due to the height of the lava fountains, north-easterly wind-direction, thermal upwelling from the lava and low air temperature.

Tephra is a synonym for all airborne, solid, eruptive materials, regardless of size an type. Tephra formation is well known in Iceland, such as in the explosive eruptions in Grímsvötn 2011 and 2004, and Eyjafjallajökull 2010. In explosive eruptions, the lava is more fragmented in the air an produces finer-grained tephra but tephra can also be produced in effusive eruptions such as is now ongoing on the Reykjanes peninsula. In effusive eruptions, the majority of tephra is deposited close to the vent and thus is not well detectable outside of the lava flow field. In May 2021, when lava fountaining was most active in the eruption in Fagradalsfjall, large pieces of tephra (up to 10 cm in diameter) fell at about 1 km distance from the eruptive source.

Tephra is sharp as glass and thus should be carefully handled. Windscreen wipers should not be used to remove tephra from vehicles as it will scratch the glass. Tephra should rather be blown or washed off with water of windows and similar surfaces.

Gas dispersion

 

Weather forecast for gasdispersion from the volcanic site is north-easterly winds, 4-8 m/s today (Thursday), thus gas is dispersed towards south-west. Decreasing wind speed tonight which can cause gas concentrations to build up at the volcanic site. Easterly and south-easterly winds, 5-10 m/s after noon tomorrow (Friday), causing gas to be dispersed to the west and north-west, towards Keflavík.

 

Updated 8. February at 11:40 UTC

The Icelandic Met Office has updated the hazard map for the area. The hazard level has increased in all areas due to the eruption.

Updated 8 February at 7:50 UTC

 

At 5:30 this morning an intense seismic activity started north-east of mt. Sýlingarfell. Around 30 minutes later, a volcanic eruption started at the site.

The eruptive fissure lengthened both towards north and south during the first minutes.

The first images from the Icelandic Coast Guard’s surveillance flight  suggest that the eruption takes place at a similar location as the eruption on the 18th of December 2023. The eruptive fissure is approximately 3 km long, from mt. Sundhnúkur in the south and stretches towards the eastern part of mt. Stóra-Skógfell. Lava flows mostly towards west at the moment and the flow seems to be slightly less than at the start of the 18th of December eruption.

 

The lava fountains reach about 50-80 m height and the volcanic plume rises about 3 km above the eruptive fissure. 

 

Image from the Icelandic Coast Guard’s surveillance flight. Mt. Stóra-Skógfell in the foreground and the lights at the Svartsengi power station to the right. (Photo: Björn Oddsson).

 

Updated 5 February 16:00 UTC

 

Ongoing magma accumulation beneath the Svartsengi-Þorbjörn area continues, even though the rate of inflation has decreased slightly in recent days. Similar processes were observed before the previous dyke intrusions and eruptions north of Grindavík in January 2024 and December 2023. According to updated geodetic models based on satellite and GNSS data covering the interval from 16 January to 5 February, the volume of magma recharge to the Svartsengi reservoir is now estimated at about 9 million m³. From geodetic modelling of the January 2024 intrusion and eruption, it is estimated that approximately 9 to 13 million cubic meters of magma flowed from the Svartsengi magma reservoir, feeding the eruption that began near Hagafell on 14 January. Therefore, the estimated volume of magma recharge has now reached the lower limit of the amount believed to have been tapped in January. Consequently, there is an increased likelihood of a new magmatic dyke intrusion and ensuing volcanic eruption in the coming days to weeks.

Since last Friday, nearly 200 earthquakes have been measured in the area north of Grindavík, most of them around or below magnitude 1 at depth of 3-4 km. The largest earthquake occurred on the morning of Sunday, 4 February, near Sundhnúkur, and was a M2.2 at a depth of approximately 6 km.

The IMO continues to closely monitor the area, and the current hazard assessment map remains valid until 3:00 PM on 8 February, if there are no changes in activity.

Latest satellite radar comparison, showing ground surface changes between 23 January and 4 February 2024. Red shading show the area of maximum inflation and grey shading shows area where measurements were not possible due to variations in snow cover between images.

 

Updated 1 February 17:00 UTC

 

Models based on GPS data, reviewed this morning (1 February) by scientists from the Icelandic Meteorological Office and the University of Iceland, indicate that approximately 6.5 million cubic meters of magma has accumulated beneath the Svartsengi region. According to this assessment, magma will soon reach the same volume as drained during the January 2024 eruption. Therefore, the timescale for the next eruption could be within two weeks or possibly days. This means that the likelihood of a magma intrusion, and a volcanic eruption, have increased.

There is no absolute certainty that the warning time ahead of the next intrusion or eruption will be the same as 14 January, which was about a five-hours’ notice from the beginning of the earthquake swarm until the eruption began just south of Hagafell. The warning period for the eruption between Stóra-Skógfell and Sundhnúkur on 18 December last year was about 90 minutes, and that eruption occurred approximately at the mid-point of the (now solidified) magma intrusion beneath the Sundhnúksgígar crater row. With repeated lateral magma intrusions, it is likely that the pathway for magma propagation to the surface will be easier, resulting in less seismicity. However, rapid movements of magma are always accompanied by increased micro-seismicity. We assess that the minimum warning time would be one-hour ahead of a volcanic eruption, and that the most likely pathway would be along the fissures from the magma intrusion on 10 November last year.

Seismic activity has been similar over the past week. Nearly 200 earthquakes have been measured in the area between Stóra-Skógfell and south of Hagafell in the past seven days. Most of these earthquakes were minor, under 1.0 in magnitude, at a depth of 2 to 5 km. The largest earthquake registered magnitude 1.8, and it was located about a kilometre south of Hagafell.

The Icelandic Meteorological Office has issued an updated hazard assessment map. The main changes are that zone 3 (Sýlingarfell – Hagafell) has been upgraded to red (high hazard), and zones 2 and 6 have been upgraded to amber (considerable hazard). Grindavík (zone 4) remains unchanged at a considerable level of hazard.

 

The overall assessment for each zone is based on a combined evaluation of seven types of hazards that could occur within individual zones. The list on the map shows hazards within the zones that are rated as “considerable”, “high,” or “very high”. Hazards rated as “high” or “very high” are highlighted in bold.

 

 

It should be noted that although the overall hazard assessment for Grindavík remains the same as last week, the lava-flow hazard is now assessed as high. The hazard of sinkholes opening over fissures within Grindavík is still rated as very high.

Updated 25 January 17:30 UTC

 

Inflation continues at Svartsengi. Over the past few days, the land has been rising at a rate of approximately 8 mm per day, slightly exceeding the recorded rate of uplift before the eruption on January 14th.

At this point, it is challenging to determine exactly how much magma has accumulated beneath Svartsengi since the eruption ended on January 16th. Most likely, the timeframe required to reach the same volume of magma as before the last eruption will be on the order of weeks, not days. Computational models are being refined to obtain a clearer assessment of the status of magma accumulation.

Low levels of seismic activity persist and are mostly concentrated around Hagafell. The current seismic activity aligns with that observed in the area following the previous eruption.

The Icelandic Meteorological Office has issued an updated hazard assessment map. The main changes include reducing the overall hazard level for Grindavík to orange (significant hazard).

It should be noted that, although the overall hazard level for Grindavík has been reduced by one level, the hazard associated with fissures remains very high. The current hazard is now referred to as “subsidence into a fissure,” describing the danger that may be present where fissures are hidden beneath unstable surfaces that could collapse and develop sinkholes.

The hazard assessment related to fissure development within Grindavík has decreased. Evaluations are underway to determine if there is a danger of existing fissures expanding or new fissures forming. GPS data have exhibited very little movement within Grindavík the past few days, reducing the assessed hazard compared to before. The hazard due to sinkholes overlying fissures is now considered significant.

(Click on the picture to see it larger). Increased hazard in the area due to the eruption near Hagafell on January 16th and land uplift near Svartsengi. Conditions within and outside the hazard areas can change with little warning. Hazard assessment is focused solely within these areas, but the danger may extend beyond them. The overall hazard assessment for each area is based on a combined evaluation of 7 types of hazards present or possible within the regions. The color of each area reflects the overall hazard within those boundaries.

 

Updated 19 January 16:30 UTC

 

Clear signals of a continued land uplift are still being detected beneath Svartsengi. It is yet too early to assert whether the rate of the land uplift has increased since prior to the eruption on January 14. First measurements suggest that is the case, but as has previously been written measurements can fluctuate from one day to the next and a longer timeline of measurement is needed to be able to interpret the long-term development of the land uplift.

Seismic activity continues to decrease in the area of the magma dyke and deformation signals seen on GPS devices suggest significant slow down of ground movement compared to previous days. This information suggest that magma is no longer flowing into the dyke and the eruption has ended.

GPS measurements also show small deformation within Grindavík. There is still high danger of ground collapse into fissures within the town and thus important to map new fissures and changes to known ones estimated.

The Icelandic Meteorological Office has updated the hazard assessment due to the volcanic and seismic activity. Hazard level has been decreased in all zones.

An overall hazard assessment for zone 1, Svartsengi, is now down to yellow (moderate hazard).

An overall hazard assessment for zone 4, Grindavík, is now down to red (high hazard). Note that the colour of zones represents the overall hazard within those zones. A hazard which is rated greater within a zone is written in bold letters in the list of hazards on the map.

The the hazard assessmept map takes effect at 15:00 today, Friday January 19 and is valid until Thursday, January 25, at 15:00, unless there are significant developments.

 

Updated 18 January 15:30 UTC

 

As reported in the news yesterday, clear signs of land rise persist beneath Svartsengi, but it is still too early to determine the rate of the uplift due to the recent volcanic activity in the area. GNSS measurements are being evaluated to provide a comprehensive assessment of the situation. However, it appears that the deformation remains similar to that observed after the volcanic eruption on December 18.

Around 200 earthquakes have been recorded near the magma conduit since yesterday, with the largest measuring 1.4 in magnitude. Since midnight, approximately 70 small earthquakes have occurred, which is fewer than measured the day before. The weather has impacted the number of earthquakes detected in recent days, but the number of earthquakes seems to have decreased overall.

A significant risk remains in Grindavík due to fissures and the potential for ground collapse into them.

Updated 17 January 18:00 UTC

 

 

Magma accumulation continues under Svartsengi. It is too early to assert the rate of the land uplift shortly after the volcanic eruption. Experts will continue to assess data from GNSS stations in the area to get an overall assessment of the situation. One of the meters, which was located north of Grindavík, went under lava, but over 20 GNSS stations are in the area and are being used.

Seismic activity has been mild over the magma conduit in the last 24 hours. According to computational models, magma lies shallow at the southern end of the conduit, where the land appears to be heavily fractured, making it easier for the magma to reach the surface. Therefore, there is a continued likelihood that new eruptive fissures may open without warning.

There is still danger within Grindavík related to fissures and the potential for ground collapse into them. Significant deformation has occurred in connection with the graben in the eastern part of the town. These movements were mostly along the fissures that formed on November 10 and had already been mapped.

Gas pollution was measured yesterday during work on wells connected to the utility system within Grindavík. The Icelandic Meteorological Office does not monitor localized gas pollution within Grindavík. It needs to be further examined whether or not the gas pollution is related to the magma lying very shallow in the area. It should be noted that dangerous gas pollution is among the issues mentioned in the current hazard assessment for Grindavík.

The IMO has issued an updated hazard assessment map. There are no changes in the overall hazard assessment for the areas compared to what was previously. The map takes effect at 15:00 today and is valid until Friday, January 19, at 15:00, unless there are significant developments.

 

Updated 16 January 18:00 UTC

 

Magma continues to accumulate beneath Svartsengi at a rate similar to that observed before the last two eruptions. This was the consensus reached during a consultation meeting of scientists this morning. During the eruption this past Sunday, similar to the December 18 eruption, magma flowed eastward from the accumulation site beneath Svartsengi, creating a magma conduit extending from Stóra-Skógfell southward beneath Grindavík. Computational models support this observation and indicate that the origin of the magma was slightly further west compared to the previous eruption, leading to variations in recent GPS measurements compared to those recorded on December 18.

As a magma conduit forms close to the surface, the Earth’s crust is strained, causing the land above the central part of the conduit to subside and form a graben. Additionally, the ground is elevated on either side of it. Computational models reviewed at the consultation meeting show that the GNSS station in Svartsengi is located at the edge of the conduit, where the land rises as the conduit forms. Now, two days after the conduit’s formation, the Svartsengi GNSS station is expected to show subsidence if magma accumulation has ceased. However, this is not observed, indicating that magma accumulation continues as before.

The magma conduit generated in the eruption that began on Sunday lies slightly further east than the conduit that extended under Grindavík on November 10. Data collected and processed by the Icelandic Institute of Natural History and the National Land Survey of Iceland reveal that a new graben has formed east of the one that appeared on November 10. The newly formed graben measures approximately 800-1000 meters in width, as shown on the map below. The greatest subsidence within it is approximately 30 cm, but it is worth noting that the region is still experiencing subsidence, and the valley is progressively widening. In comparison, the graben that developed in Grindavík on November 10 had a width of about 2 km, with the most significant subsidence measuring around 1.3 meters.

Inside this recently formed graben, previously mapped fissures that were visible on the surface have expanded, and additional fissures have emerged. Consequently, the risk associated with these fissures and the possibility of ground collapse into them have increased in the eastern section of Grindavík compared to before.

 

Map showing the location and width of the graben formed on November 10th (“Mörk sigdals 10-11. nóvember”) and the newest graben that recently formed to the east (“Mörk sigdals 14-15. janúar”).

Updated 16 January at 11:45 UTC

 

There is currently no visible activity within the eruptive fissures, with the most recent lava observed emanating from the northern fissure shortly after 1 am last night. Seismic activity continues to decrease, signifying that the area is stabilizing. Approximately 200 small earthquakes were recorded near the magma conduit since midnight, indicating that magma is still migrating. Most seismic activity is located near Hagafell, close to the first eruptive fissure that opened on Sunday morning. At this point, it is premature to declare that the eruption is over.

GPS sensors continue to detect ground deformation in and around Grindavík, illustrating that the magma conduit beneath Grindavík is still causing expansion in the area. Thermal images from a drone last night show that fissures previously mapped southwest of Grindavík have significantly enlarged. Considerable hazards persist in the area.

 

Updated 15 January at 16:40 UTC

 

Based on webcam footage, it is evident that the lava flow has decreased from the eruptive fissures that opened yesterday. Flow from the southern eruptive fissure, which emerged around noon yesterday near the town‘s border, seems to have ceased. The majority of the remaining lava flow is now directed southwest along the protective barriers, and its trajectory seems to have stabilized.

It is difficult to estimate how long this eruption will last. Seismic activity has decreased, and GPS measurements indicate that the rate of deformation in the area has reduced. However, deformation is still detected near the southernmost part of the magma conduit beneath Grindavík.

Measurements indicate that there has been a displacement of up to 1.4 meters in the past 24 hours, distributed across numerous fissures within the town‘s boundaries. Fresh fissures have developed, and existing ones have expanded. It is possible that additional fissures may emerge on the surface in the next few days.

As previously stated, the eruption sites are extremely hazardous, and the possibility of new fissures emerging without warning cannot be dismissed. This was demonstrated by the eruptive fissure that appeared near the border of Grindavík yesterday, which provided no recognizable warning signs on the monitoring equipment.

Today, there is a mild wind from the northeast at the eruption sites, but it will pick up speed later in the day. Therefore, gas pollution is drifting southwest towards the ocean. Tomorrow, the area will experience winds from the north reaching 10-18 m/s, causing the gas to drift south. Refer to the weather service’s forecast for gas dispersion details.

The Icelandic Meteorological Office continues to monitor the area and is in direct contact with civil protection and response teams in the region about the progression of the event.

Scientists met this morning for a consultation meeting organized by the Icelandic Meteorological Office. They reviewed the most recent data related to the eruption.Top of Form

In the upcoming days, there will be ongoing measurements and the collection of additional data, followed by analysis. These data are being utilized, among other things, to construct models that enhance comprehension of the pre-eruptive indicators that led up to this event and to evaluate the most likely progression of the eruption. Comparisons are also being made between the December 18 eruption and the eruption that began yesterday to enhance understanding of changes in the area and to evaluate the most likely scenarios going forward.

The Icelandic Meteorological Office has issued an updated hazard assessment map based on the latest data. It remains unchanged from the last update. The map is valid until 19:00 on Wednesday, January 17, unless new developments arise.

 

Kort, der viser lavaens udbredelse baseret på målinger udført af det islandske naturhistoriske institut og Islands Universitets institut for geovidenskab. Der blev gennemført undersøgelser to gange i går. Den mørkelilla form viser udstrækningen af ​​lavaen kl. 13.50 den 14. januar, mens den lyse lilla form viser udstrækningen kl. 16.15, næsten 2,5 timer senere. De eruptive sprækker er markeret med røde linjer, mens barriererne konstrueret for at forhindre lava i at nå Grindavík er repræsenteret af orange stiplede linjer

Kort, der viser tykkelsen af ​​lavastrømmen baseret på målinger kl. 13:50 i går.

Opdateret 14. januar kl. 15:30 UTC

 

 

Udbruddet nær Hagafell-Grindavík har bevaret samme styrke den seneste time eller deromkring.

Seismiske målinger viser, at ved begyndelsen af ​​urolighederne i morges (~2:30 om morgenen), flyttede den magmafyldte digeindtrængning sig først fra den SE-kant af Stóra-Skógfell og fortsatte derefter mod sydvest til den sydlige ende af Grindavík. Klokken 05.30 havde seismiciteten nået den nordlige ende af Grindavík, og både seismicitet og deformationsmålinger indikerer, at diget siden har forplantet sig under Grindavík by. En ny eruptiv sprække åbnede kl. 12.10 i eftermiddags, lige nord for byen. Lavastrømme ekstruderet fra denne sprække er nu kommet ind i byen.

På grund af digets udbredelse blev eksisterende forkastninger og sprækker reaktiveret, og der er sandsynligvis dannet nye sprækker i Grindavík.

 

Gas distribution

Det islandske meteorologiske kontors vejrudsigt for gasfordeling fra udbruddet ved Hagafell indikerer, at retningen er nord og nordøst, med en hastighed på 3-8 m/s, og vejret er tørt og lyst i dag. Det bliver til tider overskyet med mindre snefald sent i aften og i morgen tidlig. Det vil klare op om eftermiddagen i morgen. Forureningen fra udbruddet breder sig mod syd og sydvest.

 

Nyt Hazard Map udgivet

Det islandske meteorologiske kontor har opdateret farevurderingskortet i lyset af fortolkningen af ​​de seneste data.

Risikoen er steget på alle områder. Farevurderingskortet er gyldigt indtil kl. 19.00, mandag den 15. januar, medmindre andet er angivet.

Opdateret 14. januar kl. 8:20

 

Et udbrud startede klokken 7:57 UTC

Sprækkeåbningen er sydøst for Hagafell-bjerget.

Den sydligste del af sprækken er omkring 900 m fra byen Grindavík.

Åbningen er syd for lavastrømsafbøjningsbarrierer, der bygges nord for Grindavík. Lava strømmer nu mod byen.

Et billede taget ombord på kystvagtens fly. Sprækkeåbning kan ses med lysene i Grindavík i det fjerne. Et kort, der viser sprækkeåbningen markeret med en rød linje.

 

Opdateret 14. januar kl. 06:15 UTC

Omkring 03:00 UTC i dag begyndte en intens serie af jordskælv ved Sundhnúksgígar-kraterrækken. 

På tidspunktet for offentliggørelsen er der målt over 200 jordskælv i området, og seismiciteten har bevæget sig mod byen Grindavík. 

So far, the largest recorded earthquake is 3.5 in magnitude, and it was measured at 04:07 UTC at Hagafell. 

Both real-time GPS measurements and borehole pressure readings (from HS Orka) show major changes since the onset of today’s earthquake activity. These observations, in addition to the ongoing seismicity, confirm that magma is moving within the region. 

Our assessment is that the possibility of an eruption is high, and that it could occur imminently.

A map showing the latest earthquake activity.

Updated 12 January at 17:45 UTC

 

The Icelandic Meteorological Office has updated the hazard assessment map for the Grindavík – Svartsengi region due to the ongoing unrest on the Reykjanes Peninsula. As before, the map shows an assessment of existing hazards that could occur with little warning within the specified regions. Note that the assessment applies only for hazards within the defined areas, although hazards are possible beyond the confines of the assessed regions.

In terms of colour-coding, the overall assessment for the six zones remains unchanged from the previous map. However, there is a change in the hazard assessment associated with fissures within Grindavík (zone 4). The hazards associated with sudden opening of mapped and unknown fissures within Grindavík is now deemed higher. It should be noted that the hazards associated with fissures is limited to known areas within the municipal boundaries.

Unless otherwise stated, the map is valid until Tuesday, 16 January 2024.

 

Updated 9 January at 13:00 UTC

 

Seismic activity continues to exhibit a pattern similar to that of recent days. The earthquake activity remains relatively low, primarily centered between Hagafell and Stóra Skógfell, where the center of the intrusion is situated. Additionally, there is ongoing seismic activity in Fagradalsfjall, persisting since December 18th.

Land uplift is still being measured in the Svartsengi area, exhibiting a relatively stable trend since the eruption on December 18th. The accompanying image, marked with red dots representing data from the GPS station SENG in Svartsengi, illustrates this trajectory The recent rate of uplift is approximately 5 mm per day, resulting in a current elevation that is about 5 cm higher than before the dike intrusion on November 10th and December 18th last year.

Calculations from models relying on deformation measurements (GPS and satellite images) indicate that the amount of magma accumulated in the reservoir beneath Svartsengi has reached a level comparable to the volume that led to the formation of the magma conduit and the subsequent eruption on December 18th last year. This suggests that there is an increased risk of an eruption in the coming days.

The Icelandic Meteorological Office issued an updated hazard map on January 5th, and it will be reassessed on January 12th.

 

Relative målinger fra GPS-stationen SENG i Svartsengi fra begyndelsen af ​​oktober 2023 til i dag, viser nord-, øst- og lodrette komponenter (top, midt, bund). Den nederste kurve viser landhævningen i millimeter, med dagens måling angivet med en grøn prik.

Opdateret 5. januar kl. 17:40 UTC

 

Et nyt farekort er udstedt af IMO. Kortet afspejler en farebaseret vurdering af Grindavík – Svartsengi-regionen, foretaget den 5. januar 2024. Farevurderingen er baseret på de seneste overvågningsdata, herunder seismisk aktivitet og jorddeformation, samt geodætiske modelleringsresultater. Vurderingen tager også højde for sandsynligheden for vulkanske farer i hver af de seks zoner, som vist på kortet.

I dagens vurdering påvirker hovedændringen Svartsengi-regionen (zone 1), som nu anses for at være på et moderat fareniveau, hvilket afspejler et fald i forhold til den tidligere version af farekortet. Begrundelsen for denne ændring er, at farevurderingen på grund af dannelsen af ​​større overfladebrud er faldet, da der ikke er dannet nye større brud på det seneste. Derudover gør de seneste geofysiske observationer sammen med vores videnskabelige konsensus Sundhnúksgígar til det bedste sted for et udbrud.

I mellemtiden fortsætter IMO med at overvåge området, og eventuelle ændringer vil blive kommunikeret direkte til civilbeskyttelsen via de sædvanlige kommunikationskanaler.

 

Opdateret 5. januar kl. 14:30 UTC

 

Landhævningshastigheden nær Svartsengi fortsætter med at falde. Eksperter samlet på Meteorologisk Kontor her til morgen bekræftede dette gennem en analyse af GPS-data. Som tidligere rapporteret, signalerer dette en stigning i magmatrykket, hvilket øger sandsynligheden for et nyt digeindtrængen og potentielt udbrud. Det kan dog ikke udelukkes, at dette alternativt kan tyde på et fald i magmatilstrømningen.

Cirka 490 jordskælv har fundet sted nær magmakanalen siden tirsdag den 2. januar. Blandt disse havde 14 en styrke på over 1,0, hvoraf det største målte 1,8 nord for Hagafell. Onsdag den 3. januar indtraf et jordskælv med en styrke på 4,3 nær Trölladyngja, kort efterfulgt af et jordskælv med en styrke på 3,5 og adskillige efterskælv; omkring 900 jordskælv er blevet målt i området.

Den seismiske aktivitet nær Trölladyngja den 3. januar fandt sted langs en anerkendt brudlinje, hvor større jordskælv tidligere er sket flere gange. Der er intet, der tyder på, at disse jordskælv er direkte forbundet med magmabevægelser. Ikke desto mindre er de bemærkelsesværdige ændringer i landskabet i forbindelse med vulkansk aktivitet i Fagradalsfjall, landhævningen nær Svartsengi, magmakanalen nær Sundhnúk den 10. november og udbruddet den 18. december blevet målt på tværs af det vestlige Reykjanes og påvirker seismisk aktivitet i hele regionen .

According to their evaluation, scientists conclude that in the event magma reaches the surface, the most probable site for a subsequent eruption would again be Sundhnúksgígaröðinni, situated between Stóra-Skógfell and Hagafell. However, it is important to remember that dike intrusions do not always culminate in an eruption, as evidenced by the activity at Fagradalsfjall and also during the Krafla fires. 

 

Updated 3 January at 12:30 UTC

At 10:50 AM, an earthquake of magnitude 4.5 occurred near Trölladyngja, followed shortly by another earthquake measuring 3.9 at 10:54 AM and a series of aftershocks. The earthquakes occurred at a depth of approximately 5 km and were likely triggered in response to stress released from earth movement elsewhere on the Reykjanes Peninsula. These earthquakes were widely felt in the southwest region of Iceland.

The location of the earthquakes is about 20 km NNE of Svartsengi, where land rise due to magma accumulation is ongoing. 

The accompanying image shows the location of the earthquake that occurred at 10:50 AM and its impact area.

Updated 2 January at 14:00 UTC

 

The rate of ground displacement at Svartsengi is decreasing. Experts gathered at the Meteorological Office this morning confirmed this through an analysis of GPS data.

The deceleration of inflation is an indication that magma pressure is rising, increasing the chances of new dike intrusion and also volcanic eruption. This is a similar change in ground displacement that was observed at the end of the day on December 15, which culminated in an eruption three days later. However, it is difficult to assert whether this pattern will repeat.

The first signs of an impending volcanic eruption are a sudden increase in seismic activity, and such signs were observed shortly before the eruption began on December 18.

In recent days, seismic activity in the area has been relatively consistant, with around 200 earthquakes recorded per day. Most of the earthquakes measure below magnitude 1.0, but around 30 earthquakes with magnitudes exceeding 1.0 have been recorded since December 29, with the largest being a magnitude 2.1 located in the northern part of Grindavík.

Continued scientific assessment indicates that, should an eruption occur, the Sundhnúkur crater row, between Stóra-Skógafell and Hagafell, is the most probable location for an eruption. However, it is important to note that magma migration does not always result in an eruption, as demonstrated by the activity at Fagradalsfjall and in the Krafla Fires.

The hazard assessment map issued by the Meteorological Office onDecember 29 remains unchanged and is valid until January 5.

Seismic activity continues to be measured west of Fagradalsfjall, where around 100 small earthquakes have been recorded since December 29. Further analysis of the monitoring data will soon be conducted to obtain a clearer picture of the situation at Fagradalsfjall.

 

Updated 29 December at 15:15 UTC

The ground continues to inflate at Svartsengi. At the GPS station Svartsengi (SENG), the land has now reached a similar height as measured just before the eruption on 18 December. The rate of uplift since 18 December has remained constant, which is different from the situation before the last eruption, where uplift slowed in the days before the eruption. However, it is difficult to assert that the uplift will slow down before the next eruption, though this has been the case in eruptions on the Reykjanes Peninsula in recent years, and it was also noted during the Krafla Fires. Uncertainty remains about how much magma pressure needs to build up before magma starts moving towards the surface.

The current uplift is not accompanied by as much seismic activity as before. The reason for this is that significant stress in the area was released during the events on 10 November and 18 December. Therefore, considerably more magma needs to accumulate before seismic activity increases from its current level. Before the last eruption, there were several earthquakes over magnitude 3 and one over magnitude 4. Similar seismic activity can be expected in connection with the next magma intrusion.

As magma accumulation continues under Svartsengi, the likelihood of another magma intrusion and an eruption increases with each passing day. It is most likely that the next eruption will occur in the Sundhnúkur, between Stóra-Skógfell and Hagafell. It is important to note that magma intrusions do not always lead to an eruption, as shown by the activity at Fagradalsfjall and in the Krafla Fires.

The Icelandic Meteorological Office has issued an updated hazard map, based on the joint interpretation of data at a status meeting held today, 29 December. The overall assessment of hazard levels within the areas remains unchanged from the last update. However, changes have been made to the list of potential hazards within area 4, Grindavík, where risks due to possible lava flow and gas pollution have been added. The changes are due to increased chances of an eruption north of Grindavík. This hazard map will be reviewed on 5 January 2024.

In the meantime, IMO continues to monitor the area and any changes will be communicated directly to civil protection via the usual communication channels.

Updated 27 December at 14:20 UTC

Since 22 December, around 730 earthquakes have been recorded in the vicinity of the magma intrusion, of which 40 had a magnitude above M1. The largest earthquake over this period had a magnitude of 2.1 on 26 December, north of Hagafell. Most of the earthquakes are occurring at a depth of 4 km. Additionally, between 22 December and today, around 140 earthquakes have been located on the western side of Fagradalsfjall. Five of these earthquakes were above M1 in size and the overall depth range was 4 to 7 km.

Ground deformation continues in the Svartsengi region, and the rate of deformation is now similar to before the eruption on 18 December 2023. This means that magma continues to accumulate under Svartsengi. Therefore, it is increasingly likely that another magma intrusion will occur, possibility leading to a second volcanic eruption. Geodetic modelling results indicate that over 10 million m³ of magma were sourced from beneath Svartsengi to feed the intrusion that formed on 18 December, which led to the eruption. Based on the ongoing uplift rate, it will take one to two weeks for the same amount of magma to accumulate again underneath Svartsengi. There is still significant uncertainty on when the built-up in magma pressure will be sufficient to trigger the next magma intrusion.

It should be noted that the original magma intrusion, which formed on 10 November, extended 15 km from Kálfafellsheiði in the north to the southwest of Grindavík, just offshore. This means that magma propagated at depth beneath the entire area, including the town of Grindavík. However, the most likely source area for the next eruption is between Stóra-Skógfell and Hagafell. Based on insights from the December 2023 eruption, the likelihood for the next event increases day by day. 

The hazard assessment map issued on 22 December 2023 remains valid. Assuming an unchanged situation, a new map will be issued on 29 December.

Time-series of continuous GPS solutions from station Svartsengi (SENG). The graph shows ground displacements in three components over the past 90 days. From bottom to top they are: up, east, and north, all measured in millimetres. The blue, vertical line shows the timing of the 10 November magma intrusion, and the red line the volcanic eruption on 18 December 2023. Each data point represents a 24-hour solution, and the vertical component shows clearly the ongoing ground uplift at Svartsengi.

Updated 22 December at 17:00 UTC

As announced yesterday, the fissure eruption at Sundhnúksgígar has ended. This indicates a temporary cessation of eruptive activity. In the last 24 hours, nearly 90 earthquakes were recorded in the Grindavík, Sundhnúksgígar, and Svartsengi regions. The largest earthquake was M1.6 west of Hagafell, just after 16:00 UTC yesterday (21 December). Overall, seismicity levels are low but variable on a daily basis.

According to GPS and satellite-based measurements, ground uplift in the Svartsengi region was apparent immediately after the eruption began on the evening of 18 December. Initial measurements show that the rate of uplift is greater than before the eruption occurred. This signifies that magma accumulation continues unabated beneath Svartsengi. This development will likely lead to another dike intrusion and, ultimately, a volcanic eruption. In the event of an eruption, the most likely source region is between Stóra-Skógfell and Hagafell.

Continuous GPS measurements show that the rate of daily ground uplift at Svartsengi between 10 November, when the magmatic intrusion formed, and 18 December progressively declined. This process is likely to repeat itself, meaning that the next dike intrusion could begin with little warning when the uplift rate decreases again. Therefore, the likelihood of an eruption increases day-by-day.

Following confirmation of the end of the 18 December eruption, the Icelandic Meteorological Office has issued a new hazard assessment. The hazard map comes into effect at 16:00 UTC today (22 December), and it remains valid until 18:00 UTC on 29 December. The main changes affect zones 2 and 3, where hazard levels have reduced from very high (purple) to high (red). The hazard assessment for all other zones is unchanged. Notably, the assessment for Grindavík is unchanged from the previous map, and the hazard level remains considerable. We emphasise that conditions can change rapidly, and that weather conditions can significantly affect the sensitivity of our monitoring networks. Under such conditions, the warning time could shorten considerably.

The weather forecast for Grindavík on 23 December calls for northeast wind 10-15 m/s, intermittent snowfall, and possibly drifting snow. Temperatures will be low, between 3 to 5°C. On 24 December, winds from the north 13-18 m/s with occasional snow showers, but 10-15 m/s in the afternoon with decreasing snow showers. Intermittent drifting snow can be expected. Temperatures will be from 0 to 2°C

The latest hazard assessment map, published on 22 December, 16:00 UTC. It is important to note that new hazards could arise with little warning within the specified areas. Additionally, the assessment applies only to the specified areas, whereas hazards could extend or occur beyond the identified zones.

Updated 21 December at 12:55 UTC

Scientists who flew over the eruption site this morning confirm that no eruptive activity is visible and that lava flow from the craters seems to have ceased. Glowing is still visible in the lava field, possibly within closed channels. This was also confirmed by an Elfu staff member in Sýlingarfell. The activity appears to have diminished late last night or very early this morning. However, it is still possible that lava is flowing in closed channels, so it is premature to declare the eruption over.

Earthquake activity has continued to decrease, and over the last 24 hours, approximately 70 minor earthquakes were measured over the magma conduits. The largest quake yesterday occurred at 14:27 and measured 1.4 in magnitude, while the largest since midnight last night was magnitude 1.9. Deformation measurements at Svartsengi show little movement, but measurements over the next few days will further clarify the situation there.

Gas dispersion, mainly due to the degassing of the lava field, will be southeastward and out to sea today. Tomorrow, with a slower northeast wind, the gas will travel southwest.

At this point, it is difficult to predict the continuation of the eruption, but scientists at the Meteorological Office are constantly assessing the latest data and continue to closely monitor the area.

Updated 20 December at 18:50 UTC

The eruption that began in the Sundhnúksgígar crater row on 18 December started with considerable force, and the warning period was short. About 90 minutes passed from the first signs of seismicity until the eruption began. The eruption occurred on the magma intrusion that formed on 10 November. The magma is sourced most likely from beneath Svartsengi, where the land has risen repeatedly since 2020.

In the last 24 hours, the highest activity in the eruption has remained around the middle of the fissure that opened on 18 December. Seismic activity has been relatively steady, and there have been little changes in deformation since the eruption began. Considering this, the Icelandic Meteorological Office (IMO) assesses that the likelihood of a new eruption forming without warning nearby Grindavík has decreased. Therefore, IMO has issued a new hazard assessment map that will take effect tomorrow, Thursday, 21 December at 7:00 UTC. The hazard assessment map is valid until 28 December. It should be noted that although the likelihood of vent formation within area 4 has decreased, the hazard level in that area is nevertheless considered substantial. Even though the activity has decreased since the eruption began, the intensity of the eruption is still significant and comparable to eruptions at Fagradalsfjall. It has also been shown that the magma can reach the surface quickly, leaving little time to issue warnings.

Because of the volcanic eruption that began at Sundhnúksgígar crater row on 18 December, there is an increased likelihood of further vent openings on the original fissure. Based on the sudden onset of the eruption at Sundhnúksgígar, the warning time for new fissure openings could be very short.

Updated 20 December at 17:00 UTC

The vigor of the eruption continues to diminish. New images of the area show that currently two craters are erupting. The most active today is the crater directly east of Sýlingarfell which is the southernmost of the craters that were active yesterday.

Lava continues to mostly flow east from the volcanic vents, but a lava tongue has also run west, north of Stóra-Skógfell. The southernmost edge of the lava does not appear to be advancing. Satellite images taken last night show that the lava field is about 3.7 square kilometers in size.

Wind will turn northwesterly tonight and tomorrow, and pollution will be transported southeastward and out to sea. The Icelandic Meteorological Office regularly issues gas pollution forecasts.

There has been a significant decrease in earthquake activity, and over the last 24 hours, about 80 small tremors have been measured over the magma conduits. The largest quake was 2.2 in magnitude at 10:55 am yesterday morning, and the largest since midnight is 1.2 in magnitude.

Updated 19 December at 18:30 UTC

The eruption continues to weaken. New aerial images of the area show that there are now three vents erupting southeast of Stóra-Skógfell, down from the previous five. The lava has mostly flowed east from the eruption site, but there is also a lava tongue flowing west from the region north of Stóra-Skógfell.

Since the eruption began, about 320 earthquakes have been measured over the magma channels. The largest earthquake, with a magnitude of 4.1, occurred at 23:25 on Monday. After midnight, seismic activity significantly decreased, and since 12:00 today, only 10 earthquakes have been recorded in the region. Following the eruption at Sundhnúksgíga, the land in Svartsengi subsided more than 5 cm. Previously, the land had risen there by about 35 cm since the formation of the magma channel on November 10. It is too early to determine if magma will continue to accumulate under Svartsengi and whether the land will start to rise again.

While the eruption continues at Sundhnúksgíga, there is an increased likelihood that more vents may open along the original fissure as well as further north or south. Looking back at the lead-up to the eruption reveals that there were approximately 90 minutes between the first indicators and the start of the eruption. Therefore, the warning time for new vent openings at Sundhnúk could be very short.

Updated 19 December at 14:30 UTC

The size of the volcanic eruption at Sundhnúksgígar continues to diminish. The lava flow is estimated to be about one-quarter of what it was at the beginning of the eruption on 18 December, and a third of the original fissure is active. The lava fountains are also lower than at the start of the eruption, reaching about 30 meters at their highest. These figures are based on visual estimates from a reconnaissance flight early on 19 December.

The development of the eruption is similar to recent eruptions at Fagradalsfjall, where the fissures are starting to contract and form individual eruption vents. Presently, there are about five eruption vents spread along the original fissure.

According to information from scientists who went on a second helicopter flight with the Icelandic Coast Guard at around 04:00 UTC today, the total length of the fissure eruption has not changed much from the beginning. There was little activity at the southern end of the fissure near Hagafell, and the majority of the lava flow is heading east towards Fagradalsfjall. Two streams reach west, both north of Stóra-Skógfell.

At the time of publication, the volcanic plume is drifting from the west and northwest. Gas pollution might be noticeable in Vestmannaeyjar today, but not elsewhere in populated areas. According to the weather forecast, gas pollution might be detected in the capital area late tonight or tomorrow morning.

A new hazard assessment map is being prepared, and it will be published later today.

Amplitude image from an ICEYE satellite acquired at 03:11 this morning (19 Dec. 2023). Preliminary analysis of this image show the new eruptive fissure (yellow line) and lava flow (colored area). Notice that he dams built around Svartsengi are clearly visible.

Updated 19 December at 3:00

The intensity of the volcanic eruption, which started about four hours ago, is decreasing. This is evident from seismic and GPS measurements. The fact that the activity is decreasing already is not an indication of how long the eruption will last, but rather that the eruption is reaching a state of equilibrium. This development has been observed at the beginning of all eruptions on the Reykjanes Peninsula in recent years.

The eruptive fissure is about 4 km long, with the northern end just east of Stóra-Skógfell and the southern end just east of Sundhnúk. The distance from the southern end to the edge of Grindavík is almost 3 km.

The Icelandic Meteorological Office continues to monitor the activity and is in direct contact with civil protection and response units in the area. A meeting of scientists will be held tomorrow morning to evaluate the overnight development of the eruption.

This news will be updated at 09:00 on 19 December.

Updated 19 December at 02:10

According to the latest aerial observations and seismicity, the eruption fissure is expanding to the south. At the time of publication, the southern end of the fissure was close to Sundhnúkur. 

The eruption is located on the dyke intrusion that formed in November. The rate of lava discharge during the first two hours of the eruption was thought to be on a scale of hundreds of cubic metres per second, with the largest lava fountains on the northern end of the fissures. 

Lava is spreading laterally from either side of the newly opened fissures. From real-time GPS measurements, significant ground deformation has accompanied the opening of the eruption fissures. 

Since midnight on 19 December, the level of seismicity at the eruption site has decreased. Additionally, estimates of fissure lengthening suggest that the eruption has decreased in intensity since its onset at 22:17 on 18 December.

Updated 18 December at 23:00

 

At 22:17 this evening, a volcanic eruption began north of Grindavík on the Reykjanes peninsula. The eruption is located close to Sundhnúkagígar, about four kilometres northeast of Grindavík, and it can be seen on nearby web cameras. The eruption was preceded by an earthquake swarm that started at 21:00.

 

A Coast Guard helicopter will take off shortly to confirm the exact location and size of the eruption.

More information will be available soon.

Updated 16 December at 14:00 UTC

At this stage it is too early to say if magma accumulation at Svartsengi has stopped and the inflation is over. The rate of deformation has decreased somewhat in recent days, but more data is needed to interpret the possible development of the activity in Svartsengi.

Scientists will continue to analyze the data in the coming days. 

A new hazard map will be released on Wednesday December 20th, which will reflect the interpretation of the latest data.

Updated 15. December at 13:00 UTC

Generally weak seismicity continues in the area affected by the dike and is mostly concentrated near Hagafell.  Since Tuesday December 12, 460 earthquakes, 30 of which were greater than M1.0, have been measured. The largest earthquake in this time was M2.8 near Hagafell on Tuesday morning. Data from GPS stations and satellite images show that uplift due to the accumulation of magma continues around Svartsengi. While magma continues to accumulate in this area, further dikes or an eruption remain possible.

The hazard map published on December 6 Icelandic map here below continues to be valid until December 20. Conditions inside and outside the demarcated hazard zones can change with little warning.

Updated 13. December at 11:15 UTC

The area around Svartsengi continues to inflate. The rate of inflation has decreased somewhat since Friday, but it is still greater than it was prior to the formation of the dike that traveled under Grindavík November 10 .

While magma continues to accumulate around Svartsengi, further dikes or an eruption remain possible.

If another dike forms it is considered to be likeliest that it would follow the same path as the November 10 dike. The most likely location for a potential eruption under these conditions is assessed to be north of Grindavík in the direction of Hagafell and the area around Sundhnúkagígar. 

Seismic activity continues at a similar level to the previous days. It is generally weak and mostly in the area around Hagafell.

Updated 6. December at 18:00 UTC

Latest geodetic modelling results suggests that the magma inflow to the dike that formed on November 10 has likely ceased. The chances of an eruption happening along the dike at this time have therefore significantly decreased. However, magma accumulation continues beneath Svartsengi.  

The ongoing activity at Svartsengi, which began in October, is not yet over and a new chapter may have begun with an increased chance of a new magma propagation and, subsequently, increased likelihood of an eruption. 

As previously mentioned, the dike beneath Grindavík was fed by magma accumulating beneath Svartsengi. It is likely that this sequence of events will repeat. When looking at the overall pattern with repeated magma accumulation, it can be estimated that the next magma propagation from Svartsengi might be on a smaller scale than the one previously formed on November 10. A magma propagation could persist for several hours or days with an increased risk due to seismic activity and deformation during that period. 

Signs of a magma propagation include a sudden increase in seismic activity and rapid changes in ground deformation. These signs can be observed on instruments several hours before the magma propagation is likely to pose a threat to Svartsengi or Grindavík. If a magma propagation occurs, the Icelandic Meteorological Office will immediately activate response plans for public safety. 

Following a magma propagation, the likelihood of an eruption increases. As mentioned above, it is most likely that magma will propagate from Svartsengi into the previously formed dike on November 10. Making it the most likely area for an eruption. 

It is not possible to estimate when the next magma propagation will occur. The uncertainty is considerable, and a magma propagation could happen in the next few days or possibly after several months. 

The Icelandic Meteorological Office continues to monitor the area closely and continues to monitor any signs of magma propagation and other changes that could pose further danger in the area near Svartsengi and Grindavík.

Comparison of Svartsengi and Krafla Fires

In the last week, approximately 300-500 earthquakes were detected in a 24-hour period around the dike intrusion. The largest earthquake was a M2.7 near Hagafell on Friday evening. Since midnight today, about 90 earthquakes have been detected along the dike, all measuring below a M2.0. The majority of seismic activity continues to be concentrated along the middle of the dike at about 3-4 km depth. Due to subsidence in Svartsengi the stress in the Earth’s crust has changed. Until the previous stress level is reached, it can be expected that minor seismicity continuous in the region.

Despite the recent decrease in seismic activity in the last weeks, further unrest can be expected on the Reykjanes Peninsula. Examples of similar unrest can be seen in the Krafla Fires that began in 1975. Over a 10-year period, there were 20 magma propagations, with 9 of them resulting in an eruption (see explanatory image below). In the Krafla Fires, all of the magma propagations fed the same dike but they varied in size. A similar recurrence can also be observed in the activity around Fagradalsfjall.

De seneste geodætiske modelleringsresultater indikerer, at mængden af ​​magma, der i øjeblikket er akkumuleret under Svartsengi, er betydeligt mindre end volumen akkumuleret før digets indtrængning den 10. november. Når man ser på magma-akkumuleringen og magma-udbredelsen i Krafla-brandene, er det tydeligt, at den største mængden af ​​magma havde ophobet sig i Krafla-calderaen før det første vulkanudbrud. En mindre mængde magma akkumulerede i calderaen, før den næste magma-udbredelse fandt sted. Det kan estimeres, at en lignende udvikling vil ske i forhold til magmaophobning under Svartsengi, og der skal ophobes en mindre mængde magma, før den udløser den næste magmaudbredelse ind i diget. Det er sandsynligt, at langsomt stigende seismicitet vil blive opdaget, før en ny magmaudbredelse finder sted, hvilket indikerer øget tryk under Svartsengi.

Billedet viser samspillet mellem dannelsen af ​​diger og løft midt i Krafla-krateret. Det nederste billede viser højden af ​​land inden for Krafla-krateret, mens det øverste viser afstanden mellem Krafla-krateret og urolighederne. (Páll Einarsson og Bryndís Brandsdóttir, 2021)

Opdateret 1. december kl. 16:50 UTC

 

Seismiciteten på halvøen fortsætter med at falde. I de sidste par dage har det automatiske jordskælvslokaliseringssystem registreret relativt få jordskælv, for det meste mikrojordskælv under størrelsesordenen 1. Den seneste seismicitet er koncentreret i området mellem Sýlingarfell og Hagafell, hvor diget højst sandsynligt fødes af magma, der ophobes under Svartsengi. Nogle deformationer detekteres stadig på cGPS-stationerne tæt på diget, men signalet tolkes nu hovedsageligt som skorpens reaktion på den igangværende inflation i Svartsengi-området.

Selvom aktiviteten langs diget og dets omegn nu foregår med meget lav intensitet, fortsætter inflationen, som startede i Svartsengi få dage efter digets dannelse, med et nogenlunde stabilt tempo. Nogle cGPS-stationer omkring Svartsengi og Mt. Þorbjörn viser en langsom faldende tendens, men andre stationer viser stadig en konstant tendens, hvilket tyder på, at indstrømningshastigheden af ​​magma i dybden ikke er reduceret væsentligt.

Processen, der begyndte den 25. oktober med en betydelig seismisk sværm og toppede den 10. november med dannelsen af ​​et 15 km langt magmatisk dige, er ikke slut. Med sikkerhed kan det konstateres, at en fase er startet, hvor et lignende hændelsesforløb kan gentage sig med tiden.

På dette stadium er det dog svært at sige, hvornår den næste energiske indtrængen af ​​magma på lavere dybde kan forekomme, og om den vil forekomme i et lignende område eller ej. IMO fortsætter med at opretholde overvågningen af ​​området på et højt niveau.

 

Opdateret 29. november kl. 17:00 UTC

The seismic activity has continued to slowly decrease over the last two days. Yesterday, about 340 earthquakes were measured near the magma intrusion in the area east of Sýlingarfell, and since midnight today, around 150 earthquakes have been recorded. Most of the earthquakes have been smaller than magnitude 1.0.

The rate of uplift near Svartsengi has been decreasing, but it is still ongoing at a rate of about 1 cm per day. The majority of the displacement in the region is currently attributed to inflow under Svartsengi with a smaller portion flowing into the magmatic intrusion. In other words, the deformation measured and modeled at Svartsengi is now much greater than that seen near the magma intrusion, but all deformation signals are slowly diminishing. Observed signs of inflow into the magmatic intrusion is now limited to the area east of Sýlingarfell. Despite the slowing down of seismic activity and deformation, an eruption is still considered to be possible. If an eruption does occur, the location thought to be most likely is east of Sýlingarfell.

Here is a timeline for the GPS station Svartsengi (SENG). It shows movements over the last 90 days in the north, east, and vertical directions. The blue line marks the magma intrusion from November 10th until today.

This image depicts the movements from the station since November 10th until today.

Updated 27. November at 16:30 UTC

Seismic activity has been relatively stable for the past few days with a daily rate of about 500 earthquakes in the area of the magmatic dike. Most of the seismicity continues to be nearby Sýlingarfell and Hagafell. Around midnight a short-lived seismic swarm commenced in the vicinity of Sýlingarfell and lasted for roughly one hour. A total of 170 earthquakes were detected in the area at a depth of 3-5 km. The earthquakes were almost all very small with one M3.0.

Data from GPS stations and satellite images show that uplift continues in the area of Svartsengi and deformation is still ongoing along and around the dike. The elevated seismic activity which occurred around midnight isn´t associated with any changes to the ongoing deformation. Both seismic and deformation data suggest that magma continues to accumulate beneath Svartsengi and to flow into the middle portion of the dike which formed on 10 November. The seismic swarm that occurred this night might indicate increasing pressure within the dike.

In light of the available data and the newest analysis, an eruption along the dike is still considered likely as long as the magma inflow continues. It is assessed that the area with the highest likelihood for an eruption is in the middle part of the dike between Hagafell and Sýlingarfell. The hazard map published by the IMO on 22 November remains valid.

Additional geodetical modelling has been performed to reconstruct the evolution of the dike which formed on 10 November. These newest results suggest that the dike at depth could be wider than  initially assessed. The time needed to solidify the magma that intruded into the dike would be therefore estimated to be on the order of a few months.

This picture shows reviewed earthquakes since 24. November.

Updated 24. November at 13:30 UTC

Yesterday, around 650 earthquakes were measured near the dike intrusion north of Grindavík, and since midnight today, nearly 300 earthquakes have been detected. Most of the earthquakes are below M1.0, but the largest earthquake in the last two days was M2.7 near Hagafell. The seismic activity continues to decrease.

Data from GPS measurements show that deformation continues near Svartsengi, and deformation is still measured around the dike intrusion. However, there are indications that the rate of deformation has decreased based on data from the past week. Though, the interpretation of deformation data is complex at this stage. This is because other processes, such as fault movements related to earthquakes and the viscoelastic response of the Earth’s crust to unrest in the area, have an impact on the deformation signals.

Considering the latest interpretation of all data, the likelihood of a volcanic eruption at some location along the length of the magma intrusion persists. It is possible that magma could emerge in the area between Hagafell and Sýlingarfell. However, as crustal relaxation continues to occur and seismicity decreases, along with a decrease in magma inflow to the intrusion, the likelihood of an imminent volcanic eruption diminishes with time.

Overview of seismic activity from Friday, November 17th. The upper graph shows the number of earthquakes per hour, and the lower graph shows the number of earthquakes per day. The effects of strong wind and heavy sea swell on the Reykjanes Peninsula on November 21st and 22nd are evident in fewer recorded earthquakes due to reduced sensitivity of the seismic network during that time.

Updated 23. November at 12:30 UTC

On 21 November, approximately 300 earthquakes were detected in the region of the magma intrusion. From midnight on 22 November to 18:00 UTC on the same day, around 100 earthquakes had been recorded in the same region, which is considerably less than in recent days. Additionally, the intensity of earthquakes above magnitude 2.0 has decreased. During the period of severe weather on 21 and 22 November, efforts were made to assess how weather conditions and ocean swell influences IMO’s monitoring systems.

Magma inflow rates and crustal adjustments related to the formation of the intrusion continue to diminish. Additionally, crustal uplift near to Svartsengi continues at a similar pace. Geodetical models based on data from 21 November suggest that the influx into the intrusion is greatest near to the Sundhnúkur crater row, about 4 km northeast of Grindavík. Minor surface displacements have been detected within the graben region in and around Grindavík.

The likelihood of a volcanic eruption at some location along the length of the magma intrusion persists. It is possible that magma could emerge in the area between Hagafell and Sýlingarfell. However, as crustal relaxation continues to occur and seismicity decreases, along with a decrease in magma inflow to the intrusion, the likelihood of an imminent volcanic eruption diminishes with time.

Based on the latest data, and considering the evolution of activity since 10 November, the likelihood of a sudden eruption within the Grindavík urban area is decreasing daily, and it is presently assessed as low. It can be assumed that newly emplaced magma beneath Grindavík has solidified partially, thereby reducing the likelihood that the magma will reach the surface within the city limits. However, we emphasise that the possibility of a volcanic eruption at some point along the length of the intrusion, particularly between Hagafell and Sýlingarfell, remains plausible.

It is apparent that there is a strong connection between crustal uplift in the Svartsengi region and the sudden, initial propagation of the magma intrusion on 10 November. Models indicate that the magma in the reservoir beneath Svartsengi may have flowed eastward towards the Sundhnúkur craters, subsequently forming the 15-km-long volcanic intrusion. While crustal uplift in Svartsengi continues, it is expected that the accumulating magma may flow again eastwards, potentially reactivating the intrusion. It is also feasible that a magma intrusion could form to the west of the magma body accumulating beneath Svartsengi. Precursors to such an event would include pronounced seismicity and rapid ground displacements, both of which are monitored closely by IMO continuously.

Updated 21. November at 15:30 UTC

 

Since midnight today, 165 earthquakes have been recorded due to the ongoing volcanic unrest, all below magnitude 2.0 in size. The level of seismicity today is considerably lower than in the recent days, when 1,500-1,800 earthquakes were recorded each day. It can be expected that the intense weather affecting the country has an impact on the sensitivity of the seismic monitoring system to detect the smallest earthquakes, making it difficult to assess whether the seismic activity is decreasing overall.

The deformation associated with the magma intrusion that formed on November 10 continues. Likewise, crustal uplift continues near Svartsengi. The speed of the uplift at Svartsengi has remained almost the same during the past 24 hours.

In collaboration with specialists from the University of Iceland, IMO continues to monitor the area as effectively as possible, constantly re-evaluating and interpreting the data received.

As mentioned before, IMO has increased surveillance in and around Grindavík and the area around Hagafell. The effectiveness of this surveillance depends on the high sensitivity of earthquake and real-time GPS measurements, which are highly dependent on weather conditions. Given the weather forecast for the next two days, which indicates precipitation and significant wind, it can be expected that both seismic monitoring and real-time GPS observations will be affected. Ocean waves also create microseisms that overwhelm the low-frequency detection capabilities of seismometers on the Reykjanes Peninsula. Fog and hail showers could also affect the visual confirmation of an eruption, adding to the monitoring and assessment uncertainty.

 

Updated 20. November at 13:20 UTC

Since midnight today, over 700 earthquakes have been detected in the region of the magma intrusion, the largest of which was magnitude 2.7 near to Hagafell. 

In recent days, between 1,500 and 1,800 daily earthquakes have been measured in the region, with the largest event registering magnitude 3.0 last Friday (17 November). Based on radar imagery from 18 and 19 November 2023, the latest interferogram of the magma intrusion and the surrounding area shows significant crustal uplift in the vicinity of Svartsengi. The newly processed interferogram was reviewed by experts during the weekend (18 – 19 November) from the Icelandic Meteorological Office, the University of Iceland, and the Department of Civil Protection and Emergency Management. The results were also discussed in today’s status meeting, held at IMO. The rapid, ongoing uplift close to Svartsengi is occurring in the same area where uplift was measured before the magma intrusion formed on November 10. Geodetic models derived from satellite images show that the uplift in Svartsengi area is considerably faster than before. Generally, when a magma intrusion forms, subsidence occurs above the centreline of the intrusion, as seen in Grindavík, with signs of land uplift discernible adjacent to the intrusion. Crustal uplift in the Svartsengi region due to magma accumulating at depth has been measurable since the intrusion began to form on 10 November. Initially, the uplift sign was influenced by the formation of the intrusion, but now the dominance of deep magma recharge is apparent.

The clear sign of crustal uplift in Svartsengi region does not change the likelihood of an eruption from the magma intrusion. This is assessed, amongst other things, on the fact that the Earth’s crust over the magma intrusion is much weaker than the crust over the uplift region close to Svartsengi. As long as there is not significant seismicity in the Svartsengi region, there is not a high likelihood of an eruption at that location. Moreover, an eruption is still deemed more likely from the intrusion, particularly if there is a sudden, large inflow of magma into the intrusion.

Our monitoring and hazard assessment preparations are still based on the assumption that the situation could change suddenly with little warning. The Icelandic Meteorological Office, in close cooperation with experts from the University of Iceland, will continue to monitor the area closely, with the goal of continually interpreting and evaluating all available monitoring observations.

COSMO-Skymed interferogram spanning 24-hours between 18−19 November at 06:41. The broad uplift signal visible in orange/red around Svartsengi is indicative of a deep inflation (>5 km) taking place.

Updated 18 November at 15:00 UTC

Seismicity related to the magma intrusion that formed suddenly a week ago remains high and constant. Approximately 1,700 earthquakes have been recorded in the last 24 hours, 1.000 of those recorded since midnight. The largest earthquake during the last 24 hours had a magnitude of 2.8 and occurred near Hagafell, 3.5 km NNE of Grindavík.

Updated 17 November at 12:00 UTC

Seismicity related to the magma intrusion that formed suddenly a week ago remains high and constant, although the level of activity is substantially lower than 10 – 12 November 2023. Approximately 2,000 earthquakes have been recorded in the last 24 hours, with most activity in an area north of Hagafell, towards the Sundhnúkar craters. Most of the seismicity is micro-earthquake activity comprising earthquakes under M 1. The largest earthquake during the last 24 hours occurred at 06:35 near Hagefell; it had a magnitude of 3.0.

According to GPS measurements, ground deformation continues but at a decreasing rate. The latest geophysical models based on GPS data and satellite imagery indicate that the largest movements in the magma intrusion are occurring north of Grindavík, near Hagafell. If magma manages to reach the surface, Hagafell is thought to be a prime location for an eruption.

Subsidence over the magma intrusion remains active, although measurements show a slight slowdown from day to day. Presently, GPS stations located in and around Grindavík, near the center of the subsidence zone, show about 3–4 cm of subsidence per day.

Based on the interpretation of the latest data and model results, a volcanic eruption remains likely, with the highest likelihood of it starting north of Grindavík near Hagafell.

A map showing the extent of the subsidence over the magma instrusion in and around Grindavík. A GPS station (GRIC) located near the center of the subsidence has recorded a total subsidence of 25 cm since the beginning of the event.

 

Updated 16 November at 17:50 UTC

Over the past few days, seismicity near the magma intrusion has remained relatively stable. As of 17:00 today, about 1,400 earthquakes have been recorded since midnight, the largest being 2.9 in magnitude, sourced near Hagafell just after 13:00. Most of the earthquakes were under magnitude 2, with the highest concentration of activity near Hagafell.

Deformation related to the magma intrusion continues to be measured, although it has slowed slightly since yesterday. The latest models, derived from GPS measurements and satellite data, still suggest that the largest movements of the magma intrusion are north of Grindavík near Hagafell. If magma manages to break through to the surface, it is most likely to happen in the region of Hagafell.

Eartly today, sulphur dioxide (SO₂), a type of volcanic gas, was measured from a borehole at Svartsengi, located just north of Þorbjörn. The borehole extends eastward to considerable depth towards the Sundhnúkur crater row. The base of the borehole therefore reaches close to the location in the crust was the magma intrusion is located. Further gas measurements will be conducted tomorrow, 17 November. The detection of volcanic gas from such a borehole is another independent confirmation of the presence of magma north of Hagafell, as indicated by seismic activity and geophysical modelling results.

The likelihood of an eruption remains high. Monitoring continues for signs of shallowing seismicity and sudden crustal movements, which could be precursors to magma breaking its way to the surface. At the time of writing, no such signs had been observed.

Updated 15. November at 11:30 UTC

Since midnight, about 800 earthquakes have been measured, most of them in the middle of the magma dyke at Sundhnúk at a depth of about 3-5 km. Seismic activity has remained constant since 11^th of November. The main monitoring focus on seismic activity remains in the area of ​​the dike and Grindavík.

Deformation measurements show continued deformation in the area. They are consistent with magma still flowing into the dyke. Part of the magma dyke seems to be solidifying, especially at the edges, but not at the magma inflow area, which is believed to be near Sundhnúk.

Measurements of sulfur dioxide (SO₂) seem to show fluctuating degassing due to the magma dyke, but further measurements are needed for confirmation. Analysis of this data is currently underway in collaboration with the Chalmers University in Sweden.

The fiber optic cable of HS Orka, that runs from Svartsengi west of Þorbjörn to Arfadalsvík is beeing used as a continuous seismic measuring line with high sensitivity. This is a new technology that has developed in recent years and is now used as additional measurements in collaboration with HS Orku and ETH in Switzerland.

Overall, the situation seems to be unchanged since yesterday. The probability of an eruption is still considered high. In the event of an eruption, the most likely location is at the magma dyke.

Updated 14. November at 19:20 UTC

Earlier this week, IMO specialists installed two DOAS remote sensing instruments on Húsafell. These instruments can measure the presence and the amount of SO2 in the atmosphere. One of the DOAS instruments detected SO2 yesterday and today at the newly formed graben, located between Sundhnúkagígar and Grindavík. Because of the low amount of daylight, the measurements can be imprecise, and it took time to review the data and interpret it. In the last two days, eastern winds have been prevalent in the area, so it cannot be ruled out that recent strong seismicity has caused the release of SO2 from beneath Fagardalsfjall, as magma at that location has not solidified yet since the eruption in July 2023.

It is hard to estimate the depth from which the SO2 is being released as the process is influenced by magma pressure. However, it is thought that the magma needs to be in the upper hundred meters of the crust in order for SO2 to be released. This is one of the reasons why the DOAS instruments have been sited close to Grindavík.

DOAS (Differential Optical Absorption Spectrometer) is a tool that can detect sulfur dioxide in the atmosphere. The method relies on visible light, which travels through the atmosphere, hits a sensor in the measuring device, which is then analyzed for certain colors (wavelengths) that are missing from the spectrum. Sulfur dioxide absorbs certain wavelengths of light, which means that light hits the measuring instrument in a different way if SO2 is detected. The probe scans certain sectors of the sky, and it provides information on the concentration of sulfur dioxide within the area scanned. DOAS measurements need daylight to work, so operating such instruments in the wintertime in Iceland can be challenging.

Updated 14. November at 12:40 UTC

Since midnight, 14 November, over 700 earthquakes have been located along the orientation of the magma intrusion, the largest of which was M 3.1 near to Hagafell. Last night, 13 November, stress-triggered seismicity occurred close to Kleifarvatn, with the largest earthquake registering M 3.8 at 21:09 UTC. Today, most earthquakes are occurring along the magma intrusion, with the majority being micro-earthquakes, commonly at focal depths of 3 to 5 km.

Deformation measurements, including high-resolution aerial observations, satellite radar imagery, and ground-based GPS observations reveal continued, ongoing ground movements due to the ongoing formation of the magma intrusion. These results are consistent with continued, albeit much lower magma inflow to the region of the intrusion.

Between 12 and 13 November, the inflow is estimated at 75 m³ / s, and the average depth to the top of the magma intrusion is thought to be around 800 m. The inflow and depth estimates are derived from model-based calculations, and they are subject to uncertainty.

Throughout this period of volcanic unrest, the focus has been continuous monitoring of seismicity and ground deformation in the Grindavík – Svartsengi region. To further our monitoring capabilities, we have installed additional GPS stations in and around Grindavík. The latest measurements from these stations show that the graben-like formation is still forming and mechanically active. Furthermore, to increase our ability to warn of an eruption, we have installed ground-based SO2 detectors that overlook Grindavík and south of Sundhnúkur.

In summary, the likelihood of an eruption remains high. If an eruption occurs, the most likely location with be along the orientation of the magma intrusion, beginning as a fissure eruption.

Updated 13. November at 16:20 UTC

 

Seismicity along the magma intrusion continues, although the size and intensity of the activity is decreasing. Since midnight today, 13 November, around 900 earthquakes have been detected. The seismic activity is concentrated on the region of the intrusion, between Sundhnúkur and Grindavík at a depth of about 2–5 km.

Decreasing rates of ground deformation are seen in GPS data from Grindavík. Satellite radar results show a graben-like formation that cuts through part of Grindavík. This feature was first identified by IMO in satellite radar imagery early on 11 November.

 

This ascending COSMO-SkyMed (CSK) interferogram covers the time period 3-11 November and shows an extensive deformation field related to the dike intrusion that began on the afternoon of the 10 November within the Reykjanes-Svartsengi volcanic system. This CSK interferogram and the previous (spanning 2-10 November) supported the difficult decision made by Civil Protection to evacuate the town of Grindavík late Friday evening. It also enabled modelling of the dimensions of the dike intrusion (on the 11 November), which provided a median dike length of 15 km and top depth of less than 1 km below the surface. The imagery shows over 1-m of ground displacement in the western part of Grindavík, caused by the propagation of the magma intrusion. From geodetical modelling results, we infer that (as of 12 November) the greatest area of magma upwelling is sourced close to Sundhnúkur, 3.5 km north-northeast of Grindavík.

New geodetic modelling is currently being undertaken, using an ICEYE interferogram and GNSS observations spanning the last 24-hours, to better assess the ongoing activity and provide an estimate of the current magma inflow rates.

According to our latest estimates, the volcanic hazard assessment in and around Grindavík is unchanged from 12 November. All monitoring systems are being monitored closely in real-time, especially near Grindavík, for any indications of sudden change. The natural hazards monitoring team at IMO is operating at maximum surveillance while the Department of Civil Protection and Emergency Management coordinates short-term, temporary access to Grindavík today, 13 November.

Estimate of the vertical displacements caused by the dike during its initial propagation from Friday afternoon to Saturday morning. The displacements were estimated by combining ICEYE and COSMO-SkyMed pixel offset tracking results.

Updated 12. November at 12:30 UTC

 

Since the morning of November 11th, seismic activity related to the magma intrusion remains fairly constant. Since midnight November 12th, around 1000 earthquakes have been recorded within the dyke, and all of them have been below M3.0 in magnitude. The most seismic activity has been located in the region north of Grindavík. Most of the earthquakes are at a depth of 3-5 km corresponding to the lower part of the dyke intrusion.

GPS measurements covering the past 24 hours show that deformation associated with the dyke intrusion that formed on Friday, November 10th has slowed. This can be an indication that magma is moving closer to the surface, new models will be run as soon as new data comes in to update the model.

It was a joint assessment from the meeting, based on the latest data, that there is scope for temporary measures under the control of the Department of Civil Protection and Emergency Management to collect necessities for the residents and attend to urgent errands in Grindavík and the surrounding area. During such operations, it is necessary to increase the vigilance of the area through additional monitoring with the aim of improving the detection of magma reaching the surface. It was the opinion of the scientists that it would be advisable to start these operations immediately, as uncertainty about the progress of the event grows as the day progresses. The final decision on whether these actions will be taken, and their implementation is in the hands of public safety and the Police Chief in Suðurnes.

In light of this joint assessment has the Police Chief in Suðurnes decided to allow inhabitant to part of restricted area in Þorkötlustaðahverfi and it is only to retrieve vital items, pets and livestock. This will be organised and controlled operation by the Police. This permission only applies to Þorkötlustaðahverfi. Note, special operation is ongoing to pick up all horses in the area north of Austurver.  

 

 

This news has been updated since the latest information from the Police Chief in Suðurnes.

Updated 11. November at 18:30 UTC

At 18:00 today, 11 November, a status meeting concluded between scientists at the Icelandic Meteorological Office, the University of Iceland, and the Department of Civil Protection and Emergency Management. The purpose of the meeting was to discuss the latest measurements of seismicity and ground deformation in the region of Grindavík, in addition to reviewing the latest geophysical models and hazard assessments. From combined assessments of satellite radar imagery, ground-based GPS measurements, and seismicity, it was concluded that the ongoing dike intrusion represents a serious volcanic hazard. 

From geophysical models of the dike intrusion, it is estimated that the intrusion is propagating upwards slowly, with magma thought to be 800 m beneath the surface. The exact location of a possible eruption site is unknown, but the 15-km length and orientation of the dike gives a good indication of possible sources. The overall assessment from the status meeting was that the likelihood of a volcanic eruption is high, and that an eruption could be possible on a timescale of just days. Based on the extent of the dike, magma could emerge from its southern, just outside of Grindavik. Therefore, the likelihood of a submarine eruption has also increased, so preparations must be made for the possibility of explosive activity. A hazard area has been defined based on the location of the dike, as shown in the map.

Status map showing the location of the dike intrusion based on combined satellite radar imagery, GPS measurements, and geophysical modelling.

Updated 11. November at 12:00pm

 

Since midnight, around 800 earthquakes have been measured in the region where the magma intrusion is occurring. The earthquake activity has diminished slightly in the past hours, but it remains high. Most of the recent earthquakes have occurred close to Grindavík, where the southwest end of the magmatic dyke is estimated to be located.

Analysis of the earthquakes from today and yesterday is ongoing. The goal of this work is to better understand the evolution of the magma intrusion. Presently, the data indicates that the magma intrusion extends from Stóra-Skógsfell in the north to Grindavík in the south, where it extends beneath the sea. In accordance with the latest preliminary models, using the most recent satellite data acquired last night, the shallowest depth of the top of the magma intrusion north of Grindavík is 1.5 km. Joint interpretation of the ground and satellite measurements indicate that the size of the magma intrusion and the rate at which it is moving are several times larger than have been measured previously on the Reykjanes Peninsula. Our assessment is that an eruption, if it were to occur, will originate from the northern side of the magma intrusion. This means that there is a greater likelihood of an eruption beginning close to Sundhnjúkagígur.

Scientists are meeting regularly to interpret the data and update the latest models and hazard assessments. A meeting for journalists will be held at 12:00 at the Department of Civil Protection and Emergency Management. The current conditions and future scenarios will be discussed.

The likelihood of a volcanic eruption occurring in the near future is deemed considerable.

 

Reviewed earthquakes since 9pm last night.

Updated 10. November at 11:30pm

 

Significant changes have occurred in the seismic activity measured near Sundhnjúkagígar north of Grindavík and deformation observed in the Reykjanes Peninsula this afternoon. The seismic activity has moved south towards Grindavík. Based on how the seismic activity has evolved since 6 PM today, along with results from GPS measurements, there is a likelihood that a magma intrusion has extended beneath Grindavík. In light of this outcome, the police chief in Suðurnes, in cooperation with the Civil Protection Authorities, has decided to evacuate Grindavík. An emergency level of civil protection is now in effect. This is not an emergency evacuation. Residents of Grindavík are advised to proceed with caution.

At this stage, it is not possible to determine exactly whether and where magma might reach the surface. There are indications that a considerable amount of magma is moving in an area extending from Sundhnjúkagígum in the north towards Grindavík. The amount of magma involved is significantly more than what was observed in the largest magma intrusions associated with the eruptions at Fagradalsfjall. Further data is being collected to calculate models that provide a more accurate picture of the magma intrusion. It is currently not possible to say when this work will be completed.

 

Updated 10. November at 8pm

 

The seismic activity currently measured at Sundhnjúkagígar occurs within an area about 3 km northeast of Grindavík. The shallowest earthquakes measured now are at a depth of about 3-3.5 km.

The signs that can be seen now at Sundhnjúkagígar are similar to those seen on the eve of the first eruption at Fagradalsfjall in 2021 and are very similar to the seismic activity that was measured about a month before that eruption. The most likely scenario now, taking into account the activity that culminated in the onset of the March 19^th 2021, is that it will take several days (rather than hours) for magma to reach the surface.  

 

Earthquakes on the 10th of November (until 6:48pm). The Icelandic Meteorological Office’s seismic network is shown with triangles. Four seismic stations surrounding the current seismic activity have been showing a large increase in tremor since 3pm.

Updated 10. November at 6:30pm

 

The National Commissioner of the Icelandic Police, in consultation with the Police Commissioner of Suðurnes, has declared a Civil Protection Alert Phase due to the intense earthquake swarm that commenced 3pm today at Sundhnjúkagígar, north of Grindavík. There is the possibility for larger earthquakes than have been experienced thus far, and this sequence of events could lead to an eruption. The Civil Protection Alert Phase means that the risk is increasing, and measures are being taken to ensure the utmost safety of those who live/stay in the area. This is done by increasing precautions in the relevant area.

The Aviation Color Code has been elevated to orange (heightened unrest with increased likelihood of eruption). IMO is closely monitoring the situation. Residents are encouraged to follow the information provided on Almannavarnir.

 

Updated 10. November at 2pm

 

Earlier today, at 12:44, an earthquake of magnitude 4.1 occurred near Sýlingarfell, west of Sundhnjúkagígar. The craters are about 2-3 km northeast of Grindavík. A dense swarm of earthquakes began around 07:00 this morning in the same area, and nearly 800 quakes have been recorded since midnight, including 9 greater than magnitude 3. The depth of the earthquakes is about 5 km. Such earthquake swarms have previously been recorded in this area. It cannot be ruled out that the seismic activity near Sundhnjúkagígar is due to magma movements at depth.

Magma accumulation continues near Þorbjörn at the same depth and at a similar rate as before. It is accompanied by swarm-like seismic activity, as was noticed yesterday and this morning. While magma accumulation continues, ongoing seismic activity can be expected due to stress release in the area. Earthquakes up to magnitude M5.5 can be expected in such swarms, and the seismic activity may shift between areas. At this stage, there are no indications that magma is forcing its way to the surface.

 

Reviewed earthquakes since midnight

Updated 9. November at 12:20pm

 

Around 1400 earthquakes have been recorded in the last 24 hours. Seismic activity increased from midnight, and the SIL seismic network has detected seven earthquakes above M4.0 since then. The largest earthquake measured M4.8 at 12:46am. It was located west of Þorbjörn. It is the largest earthquake since the activity began on October 25th. Seven earthquakes M4.0 or larger in size were measured in the area from Eldvörp to the area east of Sýlingarfell. While the accumulation of magma continues, seismic activity can be expected on the Reykjavík Peninsula because the magma intrusion causes increased tension in the area.

According to GPS data at midnight, uplift continues in the area. The GPS data is being reviewed in relation to the seismic activity tonight. Since the beginning of the inflation until today, the uplift has been fairly even, although an acceleration of the process has been observed between days. The seismic activity last night and this morning is an example of this episodic seismic activity that can be expected while magma accumulation is in progress. The fact that there are now larger earthquakes than before in the area does not necessarily mean an increased rate of magma accumulation.

 

Reviewed earthquakes since midnight last night

Updated 8. November at 2:40pm

 

Approximately 1200 earthquakes have been measured in the last 24 hours, most of them in the area between Þorbjörn and Sýlingafell, similar to the day before. The largest earthquake was M3.4 at 12:31am last night, just south of Þorbjörn. The seismic activity continues at the same depth as before. It is likely that seismic activity will continue, and be episodic in intensity, while magma accumulation is ongoing. 

Uplift continues at a similar rate as before according to Satellite and GNSS data. Interferogram (InSAR) for the period 28th of October – 6th of November showing near-vertical motion confirms this, but it also shows offsets due to fault movements associated with the seismic activity. Updated models based on the same data estimate that magma continues to accumulate in a horizontal sill at a depth of about 5 km and since the beginning of the inflation event (October 27th) the average inflow is estimated about 5 m³/s (uncertainty is ±2 m³/s)

 

Interferogram (InSAR) for the period 28th of October – 6th of November shows that deformation in that period is around 7 cm. SW of Mt. Þorbjörn is an offset in the deformation signal caused by fault movements by earthquakes.

Updated 7. November at 1:30pm

 

There have been around 900 earthquakes in the last 24 hours, most of them in the area between Þorbjörn and Sýlingafell. The largest earthquake was M2.9 and occurred around 7 am this morning. The seismic activity remains at the same depth as before.

According to satellite data processed around 5 pm yesterday and covers the period between November 4-6, confirms that uplift continues around Þorbjörn. The same data shows no signs of magma accumulation in Eldvörp or near Sýlingarfell, east of Svartsengi where seismic activity has been measued in recent days.

Magma accumulation continues at a depth of around 5 km in the are NW of Þorbjörn. If October 27th is considered the starting day of the inflation event until today, the rate of uplift has been fairly constant, although an acceleration of the process has been observed between days. It is likely that seismic activity will continue, and be episodic in intensity, while magma accumulation is ongoing.  

 

Reviewed earthquake locations since 6th of November and today until noon.

Updated 6. November at 1:15pm

 

In the last 24 hours around 1300 earthquakes have been detected on the Reykjanes peninsula, of which three earthquakes were above M3. The largest earthquake was M3.6 this morning and located 3 km NE of Mt. Þorbjörn.

Deformation data shows that uplift continues in the area and there are indications on GNSS observations of an increase in inflation rates since 3rd of November. Since the start of the inflation, the uplift at the GNSS station at Mt. Þorbjörn has reached 7 cm. The deformation is caused by a sill-type intrusion at around 5 km depth. Modelling, based on data since 27th of October, indicates that the volume change associated with this inflation event has reached almost two times the volume change associated with the four previous inflation events in the same area between 2020-2022. Inflow of magma/magmatic fluids into the sill-type body is estimated at approximately 7 m3/s which is about four times greater than the highest inflow estimated during previous inflation events here.

While the inflation  continues, increased seismicity in the area can be expected from additional stress changes  induced within the crust. 

Data from GNSS station at Mt. Þorbjörn. The graph at the bottom shows the uplift.

 

Updated 4. November at 11:30pm

 

After 17:30 yesterday, seismic activity decreased considerably. In the last 12 hours, about 900 earthquakes have been detected, all under M3.0. The activity after midnight as mainly been located at Sundhnjúkagígar – NE of Þorbjörn, as well as west of Eldvörp.

Seismicity has decreased considerably since yesterday, but the development of earthquake magnitudes, number of earthquakes and their location is comparable to the development previously seen related to magma accumulation in the vicinity of Þorbjörn.

The latest deformation data shows that uplift continues in the area. This uplift is thought to be due to magma accumulation NW of Þorbjörn at 4-5 km depth. While that magma accumulation continues, increased seismicity in the area can be expected from increased stresses in the crust. Rockfall can occur following large earthquakes, so caution should be taken by steep slopes.

The Icelandic Meteorological Office continues to monitor the area closely and to meet with the Civil protection agency to discuss the situation. Signs of magma coming towards the surface would appear as increased, shallower seismicity and rapid crustal deformation at the surface as well as volcanic tremor, which is a high rate of many small earthquakes. At the moment no clear signs can be seen of any of this, but the situation can change on short notice.

Earthquakes (circles) with magnitude over 1.5, from midnight on 3 November until 10:45 on the 4 November. The colour bar to the left shows the time of the earthquakes and the size of the circles represents the relative size of the events. Locations of seismic stations (triangles) and GPS deformation stations (squares) are also shown.

 

Updated 3. November at 3pm

An earthquake of magnitude 4.3 was detected at 1:14 pm, today between Þorbjörn and Sýlingarfell. Another earthquake of magnitude 3.5 was detected at 2:01 pm in Þorbjörn. These earthquakes are thought to be due to continuing stress in the crust from magma accumulation undir Þorbjörn mountain. No volcanic tremor has been detected and the area is still being closely monitored.

Updated 3. November at 1:50pm

 

According to measurements from 11:00 am today, the uplift centered northwest of Þorbjörn continues. The uplift is caused by a magma intrusion at a depth of about 4 km. Seismic activity continues on the Reykjanes peninsula due to crustal stress changes caused by the intrusion. An increase in earthquake activity was detected after midnight and into the morning. Since midnight, around 1.000 earthquakes have been recorded in the area, with two being above M3.0 and two above M4.0. The biggest earthquake of the current swarm was measured at 8:06 am and was 4.3 in size. The biggest earthquakes last night seem to line up in a north-south direction west of Þorbjörn. This is happening on previously known fissures, where tension has been accumulating associated with plate tectonics and may curl due to tension from intrusions.

There are currently no clear signs of magma moving closer to the surface. Signs that magma is making its way to the surface would appear in shallower seismic activity and increasing tremor, which is a high frequency of small earthquakes. At the same time, sudden deformation of the surface should be measured with GPS measurements. The development of this event is closely monitored, as the course of events can change with very little notice.   

Model calculations show that the intrusion is located northwest of Þorbjörn, as shown in the accompanying image.  The most recent seismic activity has been over the intrusion itself. The earthquakes measured at Eldvörp and east of Grindavík road are due to tension from the magma intrusion by Þorbjörn, rather than signs of magma movements in those areas.

 

 

Approximate center of magma intrusion according to model calculations based on GPS and satellite images together with seismic activity from November 2nd at 8pm to November 3rd at 12pm larger that M1.0 in size. The model assumes a box-shaped intrusion, but its length and width are subject to quite a bit of uncertainty. The model will be frequently updated with the newest data once aquired, and the size and shape of the intrusion might change considerably, so there is quite some uncertainty to the model.

 

Updated 2. November at 3pm

 

GPS data from the last 24 hours indicate that uplift continues at a similar rate in the area northwest of Mt. Þorbjörn. Earthquake activity has been quite stable, but yesterday around 800 earthquakes were recorded in the area around Þorbjörn, and the largest was M3.7 at 12:56 am. Since midnight today, around 400 earthquakes have been recorded in the area, the largest measuring M2.8 at 9:51 am. More detailed analysis of recent GPS data confirms that a magma intrusion is forming at a depth of 4-5 km under the area northwest of Þorbjörn.  

It is important to note that seismic activity is will likely continue northwest of Þorbjörn, and earthquakes over M4.0 could be found in populated areas. Triggered seismic activity can also be expected in the coming days because the magma intrusion causes increased tension in the area. Rockfall can occur following strong earthquakes, so it is important to be cautious on steep slopes.  

 

Reviewed earthquakes from midnight November 1st until noon November 2nd.

Updated 1. November at 12:20pm

 

On 25 October, an intense earthquake swarm began near Svartsengi, north of Grindavík on the Reykjanes Peninsula. So far, over 10,500 earthquakes have been detected in the swarm, with over 26 earthquakes exceeding magnitude three, the largest of which was magnitude 4.5 on 25 October at 08:18 UTC.

The latest satellite radar image, acquired late on 31 October, reveals 5 to 6 cm of ground movements over 12 days, centered just northwest of Mt. Þorbjörn. The same displacement signal is seen in continuous GPS measurements from stations in the region, beginning on 27 October. The latest GPS results from 1 November indicate that ground displacements continue in the region. Combining seismic, geodetic, and satellite-based observations, we infer that a volcanic intrusion is located at about 4 km depth just northwest of Mt. Þorbjörn. Presently, there are no indications that the volcanic intrusion is becoming shallower. We expect that seismicity will continue northwest of Mt. Þorbjörn, and this could include felt earthquakes exceeding magnitude four. Triggered earthquake activity is also possible in the coming days due to stress increases caused by the intrusion. This is a likely explanation for the ongoing seismic activity detected west of Þorbjörn in Eldvörp on 1 November. Triggered seismicity is also possible due to the long-term effects of magma accumulation beneath Fagradalsfjall.

Satellitbaseret InSAR-billede af Reykjanes-halvøen, der strækker sig fra 19. til 31. oktober. Dette billede giver et indblik i jordens deformation i løbet af de sidste 12 dage. Det største deformationssignal er centreret nordvest for bjerget Þorbjörn. Fra GPS-målinger er det tydeligt, at størstedelen af ​​centimeterskalaen jordforskydning er sket siden 27. oktober.

 

Opdateret 31. oktober kl. 17.00

 

I morges kl. 8.40 begyndte en jordskælvsværm ved Þorbjörn, som varede i næsten 2 timer og var usædvanlig intens. Det største jordskælv i sværmen målte M3,7. Aktivitetens centrum var lige øst for midten af ​​den stigning, der er observeret de seneste dage. Jordskælvenes dybde blev anslået til mellem 5 og 1,5 km dybde. Jordskælvsværmen er et tydeligt tegn på magmabevægelser i dybden. GPS-målinger understøtter fortolkningen, selv om stigningen, der startede for omkring fire dage siden, er aftaget. Tidligere i dag var der et møde med civilforsvaret og interessenter på Reykjanes-halvøen, hvor de seneste målinger og mulige scenarier og svar på det aktuelle scenarie blev diskuteret.

Situationen overvåges nøje

IMO følger udviklingen nøje og ser på, om mikroseismisk aktivitet stiger tættere på overfladen, hvilket kan være et tegn på, at magma bryder sig vej gennem jordskorpen. I øjeblikket er der ingen tegn på, at jordskælvsaktiviteten bliver mere lavvandet. Situationen kan dog hurtigt ændre sig, og det er ikke muligt at udelukke et scenarie, der involverer et lavaproducerende udbrud i området nordvest for Þorbjörn. Det er vigtigt at påpege, at magmabevægelser, svarende til dem, der observeres tæt på Þorbjörn, ofte forsvinder og ikke fører til et vulkanudbrud. Ikke desto mindre kunne langvarig riftning og øget (udløst) jordskælvsaktivitet i Svartsengi-området have skabt svagheder i skorpen, hvilket gør det lettere for magma at bevæge sig til lavere dybder.

 

Gennemgået jordskælv fra midnat i dag.

Opdateret 30. oktober kl. 11.30

 

 

Sentinel-satellitdataene, der forventes at blive modtaget i går, er ikke ankommet endnu, men cGPS-dataene i området omkring Svartensgi og Þorbjörn viser, at deformationen stadig er i gang. Deformationshastigheden siden begyndelsen af ​​denne påtrængende begivenhed har været svagt faldende over tid. Foreløbige resultater fra deformationsmodeller tyder på, at den gennemsnitlige dybde, hvor den magmatiske instruktion finder sted, er omkring 4 km.

I løbet af de sidste 24 timer er omkring 1300 jordskælv automatisk blevet registreret på Reykjanes-halvøen. Det meste af denne seismicitet er placeret i en dybde mellem 2-4 km. Det største jordskælv havde en størrelsesorden M2,7 den 29. oktober kl. 11:40 UTC.

Forskere fra det islandske meteorologiske kontor foretager yderligere overflademålinger i området, herunder geokemiske observationer. Der opretholdes regelmæssig kommunikation mellem IMO, HS-Orka og Civilbeskyttelsen, mens denne uro fortsætter.

8-timers løsning til cGNSS THOB-stationen i Þorbjörn, der viser det seneste datapunkt opdateret kl. 08:00 UTC i dag

 

Opdateret 29. oktober kl. 14.00

 

De seneste cGPS-deformationsdata omkring Þorbjörn og Svartengi-området bekræfter, at deformationen, som startede 27. oktober, fortsætter. Som indledningsvis anført, er de igangværende deformationshastigheder højere end i tidligere hændelser, som fandt sted i et lignende område i 2020 og 2022. Samlet set har seismiciteten nord for Grindavík været faldende i løbet af det seneste døgn, og der er ingen væsentlige ændringer i jordskælvsdybderne. Det er dog vigtigt at understrege, at den nuværende deformation kan udløse fornyet seismicitet i området, som kunne mærkes af mennesker.

Nye satellitdata forventes at blive leveret senere i dag, og et nyt interferogram vil blive behandlet, så snart dataene er tilgængelige. Resultaterne vil give os mulighed for at identificere og fortolke de deformationsprocesser, der har fundet sted på halvøen i løbet af de seneste 12 dage. Vi forventede at offentliggøre resultaterne i morgen.

En episode med kompleks vulkan-tektonisk uro påvirker i øjeblikket Reykjanes-halvøen. Det fortolkes som et resultat af flere deformationskilder i dybden, som interagerer og påvirker et bredt område på tværs af halvøen.

8-timers løsning til cGNSS THOB-stationen i Þorbjörn, der viser det seneste datapunkt opdateret kl. 08:00 UTC i dag, den 29. oktober.

 

Opdateret 28. oktober kl. 13.30

 

De seneste cGPS-målinger, sammen med et nyligt erhvervet InSAR-billede over Reykjanes-halvøen, afslører et tydeligt tegn på jordløft, centreret omkring Svartsengi. Dette løftesignal begyndte på et tidspunkt den 27. oktober, og det afspejler en trykstigning, der sandsynligvis er forårsaget af en magmatisk indtrængen i dybden. Midten af ​​løftesignalet er omkring 1,5 km nordvest for Þorbjörn, tæt på Den Blå Lagune. I 2020 og 2022 blev lignende opløftningssignaler detekteret i samme område og med lignende geometri. Dette er nu den femte inflationsbegivenhed i området. Fra en indledende vurdering forekommer det igangværende opløftningssignal hurtigere end tidligere. I øjeblikket er der ingen indikationer på, at magma bevæger sig på lavere dybde. Situationen kan dog udvikle sig hurtigt. For eksempel er der sket betydelige fraktureringer i Svartsengi-området på grund af udløst seismicitet i de seneste dage. En sådan frakturering kunne gøre det muligt for magma at finde veje til lavere dybde.

Samlet set viser de seneste deformationsresultater fra Reykjanes-halvøen en kompleks, igangværende proces med magmabevægelser i jordskorpen. Disse processer påvirker et bredt område, herunder Fagradalsfjall (hvor langsigtet inflation fortsætter), øst for Festarfjall (hvor deformationen ser ud til at være stoppet), og – i de sidste 24 timer – viser et område tæt på Svartsengi inflation.

Den seismiske sværm, der begyndte den 25. oktober nord for Grindavík, har resulteret i over 7.000 jordskælv. Niveauet af jordskælv er reduceret betydeligt, selvom sværmen stadig er i gang, hvilket betyder, at der stadig er sandsynlighed for jordskælv.

Geophysical modelling is underway today to determine the depth and size of the uplift source close to Svartsengi. An additional satellite radar image will be available from Reykjanes Peninsula on 29 October. This image should provide an even closer insight into the recent magma movements and deformation pattens on the peninsula.

 

 

“Line-of-sight” (LOS) deformation measured by the ICEYE SAR satellite between the 26 October at 05:21 UTC and the 28 October at 05:21 UTC. Satellite data provided in collaboration with ICEYE (https://www.iceye.com/).

 

Updated 27th of October at 2pm

 

The ground-deformation signal detected since yesterday in the area East of Festarfjall is confirmed by the latest cGPS data. The horizontal displacement over the past few days is ~ 2 cm as seen at FEFC station and movement has now also been measured at another cGPS station located in Selatangar. A 1-day interferogram spanning 26 to  27 of October, does not reveal any significant changes in the area, but the signal at FEFC measured during this 24-hr period was smaller than 1 cm, likely too small to be detected by this interferogram.  cGPS stations in Grindavík and north of here show no significant changes.

The seismic swarm north of Grindavík continues with around 1000 earthquakes since midnight. A total of 5800 eqs have been recorded since the beginning of the activity. An earthquakes M4.0 was measured at 04:02 UTC on 27 October around 2 km north of Grindavík. The seismic activity is interpreted as the response of the crust to the stress changes induced by continued magmatic inflow at depth beneath the Fagradalsfjall volcanic system.

 

Displacement at cGNSS station FEFC east of Festarfjall. Blue vertical line marks the onset of a dike intrusion in July 2023 and the red line the start an eruption near Litli-Hrútur 10th of July 2023. Most recent data points show up movement and horizontal movement towards SE.

cGNSS stations at Reykjanes Peninsula. Data from stations FEFC and STAN east of Festarfjall show movement in the last day.

Updated: 26th of October at 5pm

 

The seismic swarm that commenced on 24 October continues. Over 4,000 earthquakes have been recorded on the Reykjanes Peninsula, of which 14 had a magnitude exceeding M3. Most of the activity has occurred between Stóra-Skogafell and North-East of Eldvörp. Seismicity is located between 2 and 6 km depth, with the largest earthquake (M4.5) measured on 25 October at 08:18 UTC. Scientists at the Icelandic Meteorological Office (IMO) interpret the ongoing seismic activity as triggered by stress induced by the ongoing deformation at Fagradalsfjall, which began soon after the summer 2023 eruption. The ongoing seismic swarm is expected to continue for the coming days. In the longer-term, the continued accumulation of magma beneath Fagradalsfjall could cause further seismic swarms on the peninsula.

Jorddeformationsmålinger nær Svartsengi og Grindavík viser ingen ændringer relateret til den igangværende seismiske sværm nord for Grindavík. En enkelt GPS-station (FEFC), øst for Festarfjall, begynder at vise lokaliseret bevægelse i sydøstlig retning. Disse målinger kunne indikere tilstedeværelsen af ​​magma i dybden langs fortsættelsen af ​​digeindtrængninger, der er i nordøstlige retning mod sydvest, som er dannet under Fagradalsfjall siden 2021.

Personale fra IMO fortsætter med at overvåge de seismiske uroligheder nøje. I de kommende dage vil satellitdata blive brugt til bedre at vurdere den rumlige udstrækning af enhver jorddeformation. Målingerne vil også blive brugt til bedre at forstå igangværende geofysiske processer på Reykjanes-halvøen.

 

Gennemgået udløste jordskælv fra 20.-26. oktober.

Skrevet 25. oktober: 

I nat startede en intens jordskælvsværm nær Svartsengi, nord for Grindavík. Over 1000 jordskælv er blevet opdaget der siden midnat, og sværmen er stadig i gang. De største jordskælv, der er registreret, er M3.9 kl. 5.35 UTC og M4.5 kl. 8.18 UTC. Begge disse jordskælv opstod på omkring 5 km dybde. Seneste deformationsdata indsamlet fra flere stationer omkring Þorbjörn/Grindavík området viser ikke signifikante ændringer korreleret med den igangværende seismiske aktivitet. I lyset af de data, der aktuelt er tilgængelige, fortolkes denne seismicitet som sandsynligt udløst af stressændringer relateret til tidligere påtrængende aktivitet på halvøen. Der er i øjeblikket ingen indikationer på magmavandring under Þorbjörn/Grindavík-området, men situationen kan ændre sig når som helst, og den kan udvikle sig over kort tid fra timer til dage. Som rapporteret i september er en magmatisk indtrængen i gang under Fagradalsfjall.

 

Personale fra IMO fortsætter med at overvåge området tæt og fortolke de nyeste data, efterhånden som de bliver tilgængelige.

Usikkerhedsniveauet for Department of Civil Protection er blevet erklæret på grund af denne seismiske sværm.

 

 

8-timers løsning til cGNSS THOB-stationen i Þorbjörn, der viser det seneste datapunkt opdateret kl. 08:00 UTC i dag.

Gennemgået jordskælvssteder fra midnat til middag den 25. ^oktober .

 

Automatiske lokaliseringer af jordskælv fra midnat til middag den 25. ^oktober .

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Fortsat betydelig lavastrøm

Farevurdering opdateret på grund af tephrafald

29.5.2024

 

Opdateret 29. maj kl. 19:10 UTC

• Hoveddelen af ​​eruptivspalten er omkring 2,4 km lang

• Lavaen er strømmet over Grindavík-vejen og Nesvegur-vejen

• Ekstruderingshastigheden ved begyndelsen af ​​udbruddet blev estimeret til 1.500-2.000 m ³ /s

• I nat skifter vindretningen mod sydvest. Gasforurening kan forekomme i hovedstadsområdet i aften og i morgen (30. maj)

Der er stadig et betydeligt lavaspringvand på hoveddelen af ​​sprækken, som er omkring 2,4 km lang. Den eruptive sprække strækker sig syd for Hagafell og lava strømmer kraftigt derfra, mest mod syd og vest. Lava er strømmet over Grindavík-vejen mod Þorbjörn og videre langs lavabarriererne vest for Grindavík, der oversvømmer en del af Nesvegur-vejen. En del af lavaen, der flyder mod syd, løber ind i en sprække ved Hagafell, hvor den flyder under jorden, før den kommer frem lige nord for lavabarriererne nordøst for Grindavík. En lavalap nord for Sýlingafell flyder mod vest, og den nærmer sig Grindavík-vejen ved Svartsengi.

Modelberegninger tyder på, at der fra kl. 16:30 UTC er strømmet omkring 14 millioner m ³ /s magma fra magmareservoiret under Svartsengi til Sundhnúkur-kraterrækken. Deformationshastigheden er faldet betydeligt, men magma fortsætter med at strømme fra magma-reservoiret under Svartsengi til Sundhnúkur-kraterrækken.

 

Kort før klokken 16:00 UTC begyndte eksplosiv aktivitet, da magmaen kom i kontakt med grundvandet, hvor en lava strømmer ind i en sprække ved Hagafell. Magmaet får vandet til hurtigt at blive omdannet til gasformig tilstand (damp), hvilket forårsager dampeksplosioner og tephrafald (aske).

Der er betydelig usikkerhed omkring mængden af ​​gasser fra udbrudsstedet. I nat skifter vindretningen mod sydvest og derfor føres gasforurening mod nordøst og kunne mærkes i hovedstadsområdet i nat og i morgen (torsdag). Gasfordelingsprognose kan ses her og realtidsmålinger af forskellige gasser på loftgaedi.is

Opdateret 29. maj kl. 14:50 UTC

• Et vulkanudbrud startede ved Sundhnúkur-kraterrækken kl. 12:46 UTC i dag

• Lavaen flyder over Grindavík vej

• Eruptivspalten er nu omkring 3,4 km lang

• Ekstruderingshastigheden er groft estimeret til 1.500-2.000 m ³ /s

• Seismisk aktivitet er faldet hurtigt

Det ser ud til, at det meste af kraften i udbruddet nu er i den sydlige ende af sprækken, der åbnede tidligere i dag. Ifølge oplysninger fra kystvagtens overvågningsflyvning er der en ret intens lavastrøm omkring Hagafell mod øst og derefter sydpå mod Melhólsnáma.

Den sydligste åbning af sprækken er nu mindre end en kilometer væk fra lavabarriererne nord for Grindavík.

Det første skøn fra videnskabsmænd er, at starten på dette udbrud er kraftigere end ved tidligere udbrud i området, men ekstruderingshastigheden er groft estimeret til 1.500-2.000 m ³ /s.

Opdateret 29. maj kl. 14:15 UTC

Lavaen er strømmet omkring 1 km mod vest, og der er en betydelig strøm syd for Stóra-Skógfell mod Grindavík-vejen. Klokken lidt over 14 nåede vulkanfanen omkring 3,4 km til luften. En anden vulkansk sprække åbnede sig vest for det største krater, der blev dannet i udbruddet, der startede den 16. marts 2024. Ekstruderingshastigheden er groft estimeret til at være 1.000 m ³ /s.

Gasforurening vil være mod sydøst og senere i dag mod øst og kan derfor mærkes i Selvogur og Ölfus. Vindretningen skifter i nat mod sydvest og dermed føres gasforurening mod nordøst og vil kunne mærkes i hovedstadsområdet i nat og i morgen (torsdag).

 

Opdateret 29. maj kl. 11:40 UTC

 

Intens seismisk aktivitet er i gang på Sundhnúkur-kraterrækken. En magma- udbredelse kan være i gang eller er startet, og et vulkanudbrud kan følge.  

 

Opdateret 24. maj kl. 16:00 UTC

• Stærk vind ind i natten kan påvirke følsomheden af ​​seismiske sensorer.

• Deformationsdata viser, at landhævningen ved Svartsengi fortsætter

• Omkring 18 millioner kubikmeter magma er blevet tilført magmareservoiret siden 16. marts.

• Stadig øget sandsynlighed for endnu en digeudbredelse og et udbrud

• Sundhnúkur-kraterrækken er stadig det mest sandsynlige sted for et vulkanudbrud

• Tiden for udbrudsforstadiet kan være meget kort

 

Omkring 140 jordskælv er blevet registreret i urolighedsområdet de seneste to dage, alle målte under M2,0. De fleste af jordskælvene er lokaliseret enten i området mellem bjerget Stóra-Skógfell og bjerget Hagafell eller syd for bjerget Þorbjörn. I dag er der fundet færre jordskælv i området sammenlignet med tidligere dage. Det skyldes kraftige vinde, der påvirker de seismiske sensorers følsomhed til at måle de allermindste jordskælv. Vejret forventes fortsat at påvirke de seismiske sensorers følsomhed ind i natten, men det påvirker ikke andre sensorer, der bruges til at overvåge området.

Deformationsdata viser en stabil og fortsat stigning i Svartsengi-regionen, hvilket indikerer, at magma fortsætter med at akkumulere der i dybden. Modelberegninger anslår, at ~18 millioner kubikmeter har samlet sig der siden den 16. marts, ^hvor det sidste udbrud begyndte. Det samlede volumen af ​​akkumuleret magma er mere nu end i de seneste tidligere begivenheder. Det betyder, at trykket i systemet fortsætter med at stige, og derfor kan det konkluderes, at der stadig er betydelige odds for en ny digeudbredelse efterfulgt af et udbrud. Tidspunktet for, hvornår dette vil ske, er dog ret usikkert, men forløberen kan være meget kort.

Grafen viser den estimerede mængde magma, der er akkumuleret under Svartsengi mellem vulkanudbrud eller magma-indtrængninger, der har fundet sted siden november 2023. De små ændringer, der er synlige på grafen, er inden for fejlmarginen og er blevet observeret før under magma-akkumuleringsprocessen , hvilket indikerer, at magmaproduktionen er forblevet stabil, og at der ikke er sket væsentlige ændringer i magmastrømmen under Svartsengi siden november 2023.

 

Opdateret 21. maj kl. 17:30 UTC

• Magmaakkumulering under Svartsengi fortsætter med en stabil hastighed

• Omkring 17 millioner m3 er blevet genopladet i magma-akkumuleringszonen siden begyndelsen af ​​det sidste udbrud (16. marts)

• Stadig øget sandsynlighed for endnu en digeudbredelse og et udbrud

• Den forudgående tid før et udbrud kan være kort

 

Omkring 200 jordskælv blev registreret i urolighedsområdet i løbet af sidste weekend, de fleste af dem under M1,0. Det er ligesom seismiciteten i sidste uge, hvor der blev målt omkring 40 til 80 jordskælv hver dag. De fleste af jordskælvene er lokaliseret enten i området mellem bjerget Stóra-Skógfell og bjerget Hagafell eller syd for bjerget Þorbjörn.

Magma-akkumulering fortsætter under Svartsengi-regionen, og hævningen fortsætter også med en jævn hastighed der. Mindre ændringer i hastigheden kan ses mellem dage på de følgende grafer, men generelt fortsætter tendensen med en konstant hastighed. På dette tidspunkt antages det stadig, at der er øget sandsynlighed for en digeudbredelse og/eller et udbrud ved Sundhnúksgígar-kraterrækken.

Sidste nyhedsopdatering rapporterede øget mikroseismicitet i løbet af de sidste uger i området syd for Mt. Þorbjörn og vest for Grindavík. Det blev også nævnt, at det ville være muligt, at magma kunne finde vej gennem svagheder i skorpen der. På dette tidspunkt anses dette scenarie for meget usandsynligt. Den fortolkning er baseret på ny geodætisk modellering og andre data diskuteret på et videnskabeligt møde i går, 21. maj.

Denne gradvise stigning i seismicitet er sandsynligvis et tegn på spændingsfrigivelse i og omkring digets indtrængning ved Sundhnúksgígar-kraterrækken på grund af øget tryk i magma-akkumuleringszonen under Svartsengi.

Det mest sandsynlige scenarie anses stadig for at være en digeudbredelse og/eller et udbrud ved Sundhnúksgígar-kraterrækken.

HS Orka monitors pressure changes in boreholes in the Svartsengi region. Sudden change in pressure has been one of the precursory signals seen prior to last dike propagations and eruptions. It has previously been reported that the signs of a new dike propagation would be localized seismic swarm, changes in the rate of deformation and pressure changes in boreholes. Minor pressure fluctuations were observed yesterday in a borehole in the Svartsengi region, but there was no significant increase in seismicity or deformation at the same time. Therefore, it was not assessed that the pressure fluctuations were a sign of a dike propagation.

 

Updated 17. May at 17:00 UTC

• Magma accumulation beneath Svartsengi remains stable.

• About 16 million cubic meters of magma have been added to the magma reservoir since 16 March.

• Continued increased probability of another dyke propagation and another volcanic eruption.

• Sundhnúkur crater row still the most likely location for a volcanic eruption.

• Notice of an eruption could be very short.

• Necessary to be prepared for other scenarios than a volcanic eruption on the Sundhnúkur crater row.

 

Around 50 earthquakes were detected in the area around the dyke intrusion yesterday, 16 May, most of them below M1.0.  This is similar to the seismic activity that has been detected in recent days, but about 50 to 80 earthquakes have been measured per day, most of them occurring in two main areas, between Stóra-Skógfell and Hagafell and south of Þorbjörn.

Magma accumulation continues beneath Svartsengi and land uplift is ongoing at the same rate as before. Therefore, there is still an increased probability that in the coming days a new dyke intrusion and another volcanic eruption in the Sundhnúkur crater row could occur.

The last eruption in the Sundhnúkur crater row started on 16 March. In the 62 days that have passed since then, about 16 million cubic meters of magma have been added to the magma reservoir beneath Svartsengi. This is the longest period of magma accumulation since this scenario began at the end of October 2023.

 

Updated hazard assessment and possible scenarios.

 

The Icelandic Meteorological Office has published an updated hazard assessment map that is valid until 21 May barring any developments. The hazard of gas pollution in connection with an increased likelihood of another volcanic eruption is now considered high in area 7 but was previously considerable. Due to the change, the overall hazard in the area is now assessed as considerable (organge) but was previously moderate (yellow). Hazard due to gas pollution in other areas is unchanged from last week and is assessed as considerable. Due to increased microseismicity in area 4 the hazard of earthquakes has been raised.

IMO has also updated the scenarios that are considered most likely.

Scenario 1 Volcanic eruption between Sýlingarfell and Stóra-Skógfell (Central part of zone 3 on hazard assessment map). Similar location as where the eruptions started on December 18 2023, February 8 and March 16 2024.

 

• Probable precursors are localized, small seismic swarm between Stóra-Skógfell and Sýlingarfell, acceleration of deformation and pressure changes in boreholes in the area.

• Very short notice (less than 30 minutes), even no notice due crust already being fractured.

• Lava could reach Grindavíkurvegur in 2 to 4 hours.

 

 

Scenario 2 – Volcanic eruption south or southwest of Hagafell (Southernmost part of zone 3 on the hazard assessment map). Similar location as where the eruption started on January 14, 2024.

 

•  Probable precursors are a small seismic swarm that starts near Stóra-Skógfell or Sýlingarfell and moves south, acceleration of deformation and pressure changes in boreholes in the area.

• The notice of an eruption in this zone would probably be longer than in scenario 1, but is is uncertain how much longer.

• Lava could reach the barriers by Grindavík in about 1 hour.

• A dyke intrusion extending south of Hagafell will probably cause significant fissure movements in Grindavík.

 

 

The total amount of magma in the magma reservoir beneath Svartsengi has never been more than before 10 November 2023. Other scenarios need to be considered if magma accumulation continues without magma propagation or volcanic eruption.

Hitherto, the amount of magma that has been added to the magma reservoir between magma propagations or eruptions has been considered. In the context of increasing magma pressure in the magma reservoir beneath Svartsengi, it is necessary to consider the total amount of magma estimated to be present. 

Between 25 October and 10 November 2023, more than 10 million m³ of magma accumulated beneath Svartsengi. It is estimated that about 80 million m³ of magma propagated from the magma reservoir during the formation of a 15 km long dyke intrusion on 10 November. It can therefore be assumed that about 70 million m³ of magma was present in the magma reservoir beneath Svartsengi at that point. Magma accumulation has continued uninterrupted since then and magma has outflowed at least five times from Svartsengi to the Sundhnúksgígar crater row. Four of these five times have resulted in an eruption.

Each magma propagation or volcanic eruption has not exhausted the magma accumulation area, and therefore the initial status of magma accumulation beneath Svartsengi has varied in each cycle after November 2023, as shown in the figure below.

Caption: Graph showing the development of magma accumulation and the estimated total amount of magma in the magma reservoir beneath Svartsengi since October 25. Each magma propagation did not exhaust the reservoir, and therefore the starting status of accumulation beneath Svartsengi will vary in each cycle after November 2023. The graph shows that the total amount of magma has never been higher since the forming of the 15 km long dyke on November 10.

There are some similarities between this sequence of events in the Sundhnúkur crater row and the one that occurred in the Krafla Fires that started in 1975, Over 10-year period, there were 20 magma propagations, 9 of which ended in an eruption. During the Krafla Fires, the propagations all fed into the same dyke intrusion, but varied in size. Experience from the Krafla Fires suggests that as the number of magma propagations increases, more pressure is needed to trigger them. Therefore, it must be considered likely that magma will flow again from the magma reservoir beneath Svartsengi into the Sundhnúkur crater row.

Caption: Figures showing the correlation between the formation of a dyke intrusion and the land elevation in the middle of the Krafla caldera. The lower figure shows the elevation of the measurement point within the caldera, while the upper figure shows the distance (km) of events from the Krafla caldera in each event, with red color representing a volcanic eruption (Páll Einarsson and Bryndís Brandsdóttir, 2021).

The total amount of magma in the reservoir beneath Svartsengi has never been higher since the 15 km dyke instrusion formed on 10 November. As more time passes without a new magma propagation into the Sundhnúkur crater row, the likelihood of magma finding its way to other areas where weakness is found in the Earth’s crust increases.

Micro-seismic activity has been ongoing for the past few weeks in the area south of Þorbjörn, in the large rift valley by Grindavík. In this area, there are weaknesses in the Earth’s crust and thus magma could reach the surface there. The fact that magma flows from the magma reservoir to the area south of Þorbjörn is at this point in time a less likely scenario than the ones mentioned above. Therefore, this scenario is not taken into account in the updated hazard assessment. The Icelandic Meteorological Office will collect and process data over the next few days to shed a better light on this possibility.

The map shows earthquakes from 10-16 May. The upper graph shows the magnitude of the earthquakes and the lower graph show the number of earthquakes each day for the same period.

 

Updated 16 May at 13:00 UTC

• Magma accumulation beneath Svarstengi continues at a steady rate.

• About 16 million cubic meters of magma has been added to the magma reservoir.

• Increased probability of another dyke propagation and/or a volcanic eruption in the coming days.

• Sundhnúkur crater row is the most likely location of another eruption.

• An eruption could start with very little (or no) warning time

 

Around 80 earthquakes were detected in the area around the dyke intrusion yesterday, 15 May, most of them below M1.0. This is similar to the seismic activity that has been detected in recent days, but about 50 to 80 earthquakes have been measured per day, most of them occurring in two main areas, between Stóra-Skógfell and Hagafell and south of Þorbjörn. Signs of new magma migration from the Svartsengi reservoir to the previous diking area, may comprise localized small seismic swarms in and around the intrusion, rapid changes in deformation and pressure changes in boreholes in the area.

Magma accumulation continues beneath Svartsengi and land uplift is ongoing at the same rate as that observed since early April 2024. Therefore, there is still an increased probability that in the coming days a new dyke intrusion and another volcanic eruption in the Sundhnúkur crater row could occur.

Prior to previous dyke intrusions and volcanic eruptions, about 8 to 13 million cubic meters had been added to the magma reservoir before the reservoir failed and magma flowed from this to the Sundhnúkur crater row. Now, the amount of magma that has been added is more than the upper limit, as a total of ~16 million cubic meters have been added to the reservoir since 16 March, when the last eruption started.

Lesson learned from the Krafla Fires was that as the number of dyke propagations increases, more pressure is needed to trigger them. Therefore, it must be considered likely that magma will once again flow from the Svartsengi magma reservoir to the Sundhnúkur crater row, but there is an uncertainty as to when sufficient pressure will be reached to trigger a new dyke propagation and/or eruption.

 

 

The graph shows the estimated amount of magma that has been recharged to the  Svartsengi magma reservoir between the eruptions or dyke propagations that have occurred since November 2023. In previous dyking events and eruptions, about 8 to 13 million cubic meters has been added to the magma reservoir before the reservoir failed and magma flowed into the Sundhnúkur crater row. Now the magma amount has surpassed the upper limit, as ~16 million cubic meters have been added to the reservoir since 16 March, when the last eruption began.

 

Updated 13 May at 15:00 UTC

• There is an increased likelihood of a new dike intrusion and another eruption in the coming days.

• The most likely location for a new eruption is the Sundhnúk crater row.

• Warning signs preceding an eruption could be very short.

 

Ground uplift continues in the Svartsengi area at the same rate as previously observed. Since March 16th, when the last volcanic eruption began, ground uplift has reached approximately 20 cm at the GNSS station in Svartsengi. Magma accumulation continues in the reservoir, and the likelihood of a new dike intrusion and a new eruption continues to increase.

In the previous dike intrusions and eruptions over the past several months, approximately 8 to 13 million cubic meters of magma were recharged to the reservoir beneath Svartsengi between events before the magma migrated to the surface towards the Sundhnúk crater row. Now, the volume of magma added since March 16th has exceeded the previously observed upper limit.

Seismic activity is relatively stable between days. In the last week, approximately 50 to 80 earthquakes were recorded per day, mostly occurring in the areas between Stóra-Skógfell and Hagafell and south of Þorbjörn. Most of the earthquakes have magnitudes below 1.0, but isolated earthquakes with magnitudes close to 2.0 have been recorded. Signs of a new dike intrusion are expected to be similar to those previously observed, such as localized seismic activity in and around the dike, fast ground deformation, and pressure changes in nearby boreholes.

The Icelandic Meteorological Office continues its 24-hour surveillance of the area. New eruptive fissures could open in the area between Stóra-Skógfell and Hagafell, and signs of magma migrating towards the surface would likely resemble the initial phases of other recent eruptions in the area. This could occur with little to no warning.

The graph shows the estimated volume of magma that has recharged beneath the Svartsengi area between the series of volcanic eruptions and dike intrusions that began in November 2023. Note that a geomagnetic storm over the weekend disturbed the measurements. (See discussion below.)

Disturbance in GNSS measurements due to the geomagnetic storm

Land uplift is calculated by measuring the change in the amount of time it takes for a signal to travel from satellites orbiting the earth to GNSS receivers on the ground. If the duration of time for the signal to travel between the satellite and the receiver decreases, it indicates that the land has risen.

Over the weekend, one of the most powerful geomagnetic storms in recent years occurred when solar winds from large sunspots on the Sun hit the Earth. The last geomagnetic storm of a similar magnitude occurred on October 30, 2003.

Strong solar winds send charged particles into the Earth’s magnetic field, affecting signal transmissions between GNSS receivers on the ground and satellites. This interference affects the travel time of the signal, causing deformation measurements that could be interpreted as a slowdown in magma accumulation rate. However, this is not the case, as a new data point calculated this morning is at a “normal” location compared to previous measurements. (See graph above).

Disturbances due to geomagnetic storms do not affect the Icelandic Meteorological Office’s ability to provide warnings of imminent dike intrusions or eruptions.

 

Updated 10. May at 18:00 UTC

• There is an increased likelihood of a new dike intrusion and another eruption in the coming days.

• The most likely location for a new eruption is the Sundhnúk crater row.

• Warning signs preceding an eruption could be very brief.

• An updated hazard assessment map has been issued.

 

The trend of land rise at Svartsengi has remained relatively stable since the most recent volcanic eruption ended, with magma accumulation continuing at a similar rate. As of today, it is estimated that approximately 14 million cubic meters of magma has been added to the magma chamber since the eruption began on March 16th.

In the dike intrusions and eruptions over the past few months, approximately 8 to 13 million cubic meters of magma was added to the chamber beneath Svartsengi before it exited the chamber and travelled towards the Sundhnúk crater row. Now, the amount of magma added has surpassed the previously observed upper limit. Observations from the Krafla eruptions can add context to this behavior, revealing that, as more dike intrusions occur, more pressure is required to initiate them. Therefore, it is likely that the magma chamber beneath Svartsengi will eventually feed another intrusion into the Sundhnúk crater row. However, there is uncertainty about when sufficient pressure will be reached to initiate a new dike intrusion and potentially an eruption if magma reaches the surface.

Graph showing the estimated amount of magma that has accumulated beneath Svartsengi between the eruptions and dike intrusions that have occurred on Reykjanes since November 2023.

The Icelandic Meteorological Office continues its 24-hour surveillance of the area to closely monitor the activity. New eruptive fissures could open in the area between Stóra-Skógfell and Hagafell and may resemble the initial phases of other recent eruptions in the area. This could happen with little to no warning. Signs of a new dike intrusion would be similar to those previously observed: localized earthquakes in and around the dike, accelerated deformation, and pressure changes in nearby boreholes.

Increased seismic activity has been recorded at the Sundhnúk crater row in recent days. This increase in seismic activity is likely a sign that stress is being released in and around the recent eruption site on the Sundhnúk crater row due to increased pressure in the magma chamber beneath Svartsengi.

Last night, the Icelandic Meteorological Office’s 24-hour surveillance team detected an increase in localized seismic activity south of Stóra-Skógfell, in a similar location to where previous eruptions have started. Deformation and pressure measurements, which would indicate a dike intrusion, did not exhibit significant changes. The activity persisted for a relatively short duration, but it cannot be ruled out that a small amount of magma may have been injected there.

Dangerous to be travelling near the Sundhnúk crater row

The Icelandic Meteorological Office has issued an updated hazard assessment. The termination of the last eruption has caused updates in several areas, but the current hazard assessment reflects increased chances of a new dike intrusion and possible eruption.

As the crust between Stóra-Skógfell and Hagafell is heavily fractured, magma is likely to find a clear path to the surface without significant resistance, and therefore, substantial seismic activity may not accompany magma migration through the crust. Therefore, warning times before a new eruption could be very brief or nonexistent, so it is important to exercise extreme caution when travelling to area 3, defined on the Icelandic Meteorological Office’s hazard map. The new risk assessment is valid until May 14th, unless the situation changes.

 

Updated 7. May at 17:45 UTC

• Land rise continues in Svartsengi

• The rate of magma accumulation remains similar to that observed in recent weeks

• Visible activity in the active crater has decreased in recent days

• There is a growing likelihood that the current eruption may increase in intensity or that a new eruptive fissure may open

• Warning of increased volcanic activity or a new eruption could be very brief

• The gas dispersion forecast can be followed here

• The hazard assessment remains unchanged

 

The eruption at the Sundhnúk crater row continues. Lava continues to flow a short distance from the active vent, but activity within this crater is decreasing. Over the past week, little to no change has been observed in the southern part of the lava field near the defensive barriers east of Grindavík.

Magma accumulation and land rise continue in Svartsengi. The rate has remained consistent in recent weeks (see figure below). These measurements indicate that pressure continues to rise in the magma chamber. Therefore, a new dike intrusion from the magma chamber beneath Svartsengi towards the Sundhnúk crater row remains possible.

Seismic activity has increased steadily in and around the eruption area over the past week. Most of the earthquakes, which are generally smaller than magnitude 1, are located north of the current eruption site, between Sundhnúk and Stóra Skógfell, south of Þorbjarnar in the large valley near Grindavík, and between Grindavík and the current eruption site. This gradual increase in seismic activity is likely a sign that stress is being released around the eruption site on the Sundhnúk crater row due to increased pressure in the magma chamber beneath Svartsengi.

This figure shows a map with the locations of earthquakes since April 15^th (left), along with automatic magnitudes (top right) and the number of earthquakes per day (bottom right).

These are the most likely two scenarios regarding the continuation of activity at the Sundhnúkur crater row:

 

• New eruptive fissures could open in the area between Stóra-Skógafell and Hagafell, and/or the current eruption site could expand due to a sudden increase in lava flow, which may be comparable to the initial phases of the last volcanic eruption in the area. This could occur with very little to no warning.
• It is also possible that the flow of magma from the magma chamber beneath Svartsengi into the active vent at the Sundhnúkur crater row may increase steadily until there is equilibrium between the inflow of magma into the chamber and the outflow onto the surface.

 

Signs of a new volcanic eruption would likely include a sudden increase in earthquakes in and around the eruption area, an acceleration in deformation, and pressure changes in nearby boreholes. It is important to understand that warning times could be nonexistent or very short, possibly less than half an hour.

The hazard assessment remains unchanged since the last update. In the past week, the risk of possible active lava flows in area 4 (Grindavík) has increased from considerable to high, based on the scenarios now considered most likely.

(Click on the map to see a larger version)

It is difficult to predict when there might be an end to the ongoing sequence of unrest that began in late October

As previously stated, there is still uncertainty about the progression of this episode now that the volcanic eruption has been ongoing for over a month, while magma continues to accumulate in the magma chamber beneath Svartsengi. Although the scenarios outlined above are considered to be most likely, close monitoring is ongoing to determine if magma is seeking paths other than towards the Sundhnúk crater row. Areas north of Stóra-Skógfell and south of Hagafell and Þorbjarnar are being closely monitored.

If magma moves towards the surface outside of the areas where recent eruptions have already occurred, the warning signals are expected to be more significant, manifesting with stronger and more intense seismicity than observed in the lead-up to the most recent eruptions.

 

 

Updated 2. May at 18:00 UTC

• Land rise continues at Svartsengi. Pressure continues to build up within the magma chamber.

• Lava flow from the crater, which has been decreasing in recent days, continues.

• Measurements and simulations indicate that there is significant uncertainty about the future. The likelihood of a new volcanic eruption and/or an increase in the intensity of the eruption at the Sundhnúkur crater row is growing.

• There is a risk that lava may breach the eastern defenses of Grindavík if the eruption’s strength increases again.

• The hazard assessment remains unchanged.

 

Land deformation continues to be measured at Svartsengi, and the rate of uplift has remained stable in recent weeks (see image below). Earlier in the week, there were indications that the rate of land rise might have slowed in the preceding days. However, measurements since then reveal that the rate has remained steady in the context of the past few weeks. Pressure continues to increase within the magma chamber, and there is a risk that the magma chamber beneath Svartsengi will feed a new volcanic eruption.

The graph shows ground movement in the vertical component at the GPS station SKSH in Svartsengi. The measurements indicate that the rate of land deformation has remained steady since the beginning of April. The blue line represents the timing of the magma intrusion, which did not culminate in an eruption, while the red lines represent diking events that resulted in an eruption. The second red line shows the onset of the ongoing volcanic eruption.

Seismic activity has increased along the Sundhnúkur crater row in recent days. These earthquakes are small, likely representing a release of stress within and around the increasingly pressurized magma chamber beneath Svartsengi.

Lava flow from the active crater is significantly lower than it was three weeks ago, and the ccurrent flow rate is measured to be relatively small. However, an eventual increase in flow rate must be considered despite the currently minimal lava flow.

The accompanying map shows changes in the thickness of the lava flow between April 15th, April 25th, and April 30th.

Lava from the crater has been accumulating near Grindavík’s eastern defense wall in recent weeks (L12 on the image above). If the intensity of the eruption increases or new fissures open south of the current eruption site, it is expected that the lava flow will advance towards the eastern defenses of Grindavík. On Saturday, April 27th, small lava flows crossed the defenses east of Grindavík. If the power of the eruption increases again, there is a risk that such occurrences will become more frequent.

These are the most likely two scenarios regarding the continuation of activity at the Sundhnúkur crater row:

• New volcanic fissures could open in the area between Stóra-Skógafell and Hagafell, and/or the current eruption site could expand due to a sudden increase in lava flow, which may be comparable to the initial phases of the last volcanic eruption in the area. This could occur with very little or no warning.

• It is also possible that the flow of magma from the magma chamber beneath Svartsengi into the active vent at the Sundhnúkur crater row may increase steadily until there is equilibrium between the inflow of magma into the chamber and the outflow onto the surface.

Precursory signals of a new volcanic eruption would resemble previous events, with sudden and intense seismic activity within and around the magma chamber and land deformation in Svartsengi.

The hazard assessment by the Icelandic Meteorological Office remains unchanged and is valid until May 7th, unless the situation changes.

Follow the meteorologist’s forecast for gas emissions here.

 

Updated 26. April at 17:30 UTC

• Part of the lava field near the barriers east of Grindavík continues to thicken slowly.

• Ground uplift in the Svartsengi area continues at constant rate.

• As long as the magma continues accumulating in the Svartsengi reservoir, the likelihood for a significant escalation in the eruptive activity in Sundhnúk crater row increases.

• Continued hazard due to gas emissions in the area.

 

The eruption at Sundhnúkur continues with one crater, just east of Sundhnúkur, remaining active as of 5 April. Lava flows travel a short distance to the south of the crater in an open lava channel but progress further in closed channels. Part of the lava field near the barrier east of Grindavík continues to thicken slowly.

Image from the Icelandic Meteorological Office‘s web-camera taken at 4:30 this morning, shortly before sunrise. The camera is located on top of Þorbjörn and looks northeast towards the crater.

Ground uplift in the Svartsengi area continues at constant rate. Analytical models suggest that the amount of magma recharged within the reservoir beneath Svartsengi, since the eruption began on 16 March, is now approaching 10 million m³, as is shown in the graph below.  In previous events, magma started propagating as dike intrusions from the reservoir at 4-5 km depth towards the surface when a threshold of about 8-13 million m³ of recharged magma was reached.

The graph shows the estimated amount of magma that has been recharged beneath the Svartsengi area between volcanic eruptions or magma propagations that have occurred since November 2023.

As long as the magma continues accumulating in the Svartsengi reservoir, the likelihood for a significant escalation in the eruptive activity in Sundhnúk crater row increases.

 

• New eruptive fissures may open up in the area between Stóra-Skógfell and Hagafell and/or the current eruptive fissure may enlarge due to a sudden increase in lava flow, which could be similar to the initial phase of the last eruptions in the area. This could happen with very short, if any, precursors.
• It is also possible that if more magma starts propagating from the Svartsengi reservoir to the Sundhnúks crater row, this could happen gradually until a balance between the inflow rate at depth and the extrusion rate at the surface is reached.

 

There is also a possibility of a new dike intrusion resulting in a new volcanic fissure opening up elsewhere than in the area between Stóra-Skógfell and Hagafell. This scenario is considered less likely than the others, and longer and more intense precursors are expected to occur.

On Wednesday, 24 April, experts from the Icelandic Meteorological Office carried out measurements of gas release from the eruption. It was estimated to be 6-9 kg/s of SO₂, whereas in the last measurement, carried out two weeks ago on 12 April, the gas emission was estimated at 10-18 kg/s. This is not a confirmation that the trend in gas emission from the eruption is reducing. In fact, while the eruption continues, emissions of SO₂ can vary greatly between days (as was observed during the eruptions at Fagradalsfjall). There continues to be a hazard due to gas emission in the area around the crater as well as in settlements in the Reykjanes peninsula, and we advise people in the area to monitor air quality and familiarize themselves with the response to air pollution from the eruption.

 

Volcanic gas pollution (SO₂) in the atmosphere was clearly visible in a satellite image (Sentinel 5p) taken yesterday, 25 April at 14:27 UTC.

The weather forecast predicts northerly winds of 5-10 m/s today, Friday, and gas pollution will be dispersed to the south of the eruption site and could be felt in Grindavík. The weather forecast for gas dispersion is here.

 

Updated 23. April at 18:00 UTC

 

The eruption continues from the single vent which formed just East of Sundhnúkur, in a similar manner since 5 April. Lava continues to extrude and propagate towards the South along open channels, which are clearly visible from the cameras. The lava is also travelling longer distances from the crater through a network of closed tubes, which prevents the lava from cooling by direct contact with the atmosphere. The sector of the lava field which has been propagating towards the South, and reached the protective barriers built East of Grindavík town, has been thickening in the past few days, as shown in the images below. The images show the differences in the lava field profile between 18 and 23 April. The image at the top is taken from the camera owned by the Icelandic Civil Protection which is located at the barrier East of Grindavík and looks toward the part of the lava field which propagated towards Suðurstandavegur at the beginning of the eruption. The image at the bottom is also from a camera owned by the Icelandic Civil Protection and it is located on top of Hagafell hill and is oriented to the South. 

Estimates of the lava extrusion rate show values between 3-4 m3/s since the beginning of April. The last measurements were made on 15 April, so we are now waiting for new acquisitions which will be available next week, to shed light on the level of the current activity and to understand if there have been any significant changes.

Image from the camera, owned by the Icelandic Civil Protection, which is located at the protective barrier East of Grindavík town. The camera is oriented to follow the lava tongue which propagated towards Suðurstrandavegur at the beginning of the eruption. The yellow box indicates where the lava field has been thickening the most over the past few days.

Image from the camera, owned by the Icelandic Civil Protection, which is located on top of Hagafell hill and is oriented towards the south. The yellow box indicates where the lava field close to the potective barrier has been thickening the most over the past few days.

The ground uplift measured around the Svartsengi region continues, indicating that magma accumulates at depth at a stable rate and the total inflow to the reservoir is greater than the outflow feeding the eruption. By using analytical models, constrained by both GNSS and InSAR data, it is assessed that between 7-8 million m3 of magma has been recharged to the Svartsengi reservoir since the eruption commenced on 16 March. In previous events, magma started propagating as dike intrusions from the reservoir at 4-5 km depth towards the surface when a threshold of about 8-13 million m3 of recharged magma was reached.

As long as the magma continues accumulating in the Svartsengi reservoir, the likelihood for a significant escalation in the eruptive activity in Sundhnúk crater row increases. 

 

• New eruptive fissures may open in the area between Stóra-Skógfells and Hagafells and/or the current eruptive vent may enlarge because of a sudden increase in magma flow rate, which might reach levels comparable to those observed at the beginning of the past four eruptions which occurred in the area. If this happens, very short precursors, if any, are expected. 
• It is also possible that if more magma starts propagating from the Svartsengi reservoir to the Sundhnúks crater row, this could happen gradually until a balance between the inflow rate at depth and the extrusion rate at the surface is reached.

 

There is also the possibility that a new dike intrusion will result in the opening of additional eruptive fissures in areas other than between Stóra-Skógfells and Hagafells. This scenario is, however, considered less likely than those previously stated, and if this happens, longer and more intense precursors are expected to occur. 

Updated hazard map

During the scientific meeting this morning, the hazard assessment for the ongoing activity was reviewed. The likelihood of opening of eruptive fissures within Zone 1 (Svartsengi), Zone 4 (Grindavík) and Zone 7 has been reduced from being considerable to low. 

On Friday last week, due to the continued inflation of the Svartsengi reservoir, and the high uncertainty regarding this new situation and possible outcomes, the decision was made to temporarily increase the likelihood for eruptive openings within these areas. However, following the meeting today, it has been agreed that there is currently no evidence for an increased probability of eruptive openings in these areas. 

While the eruption continues, it is assessed that if increased magma flow occurs, the magma will most likely follow the open pathways feeding the current eruption and/or new eruptive fissures may form nearby. For this reason, the likelihood of eruptive openings without warning is still assessed to be very high within Zone 3 (Sundhnúks crater row), which remains unchanged.

 

Updated 19. April at 15:30 UTC

• Ground uplift in Svartsengi continues at a steady rate.

• Since 5 April, only one crater has erupted and lava flow from it has remained relatively stable since then, just over 3 m³/s.

• Continued hazard due to gas emissions. People are advised to monitor air quality.

• The weather forecast for gas dispersion is here

• Continued magma accumulation beneath Svartsengi at current rate increases likelihood of another magma propagation in the coming days or weeks, despite the ongoing eruption.

 

When the eruption started on the 16 March, ground uplift at Svartsengi slowed down considerably and almost stopped. This indicated an equilibrium between magma inflow into the magma reservoir below Svartsengi, and to the surface at the Sundhnúkur crater row (Figure 1).

At the beginning of April, ground uplift began to increase anew, and a similar volume of magma is now being erupted at Sundhnúkur as is accumulated in the reservoir beneath Svartsengi, causing increased magma pressure (Figure 2).  

The current development is new, which is an ongoing volcanic eruption with a relatively stable lava flow at Sundhnúkur crater row at the same time as ground is uplifting in Svartsengi. Therefore, there is more uncertainty now than before about the possible development of the event.

(Image 1)

 

(Image 2)

 

Model calculations indicate that over 6 million m³of magma has now been added to the magma reservoir beneath Svartsengi since 16 March. In previous events, magma has propagated from Svartsengi when between 8 and 13 million m³ has been added to the reservoir since last event.

The graph shows the estimated amount of magma that has been added beneath Svartsengi between the volcanic eruptions and magma propagations that have occurred since November 2023.

More uncertainty concerning the development of the activity in the next days or weeks.

Hitherto, the general trend in Sundhnúkur area has been increased likelihood of magma propagation and even a subsequent eruption. Now however, a new situation seems to be at hand when a magma propagation could occur during an ongoing eruption. Let’s recall that magma propagation is a sudden and large flow of magma propagating out of a magma reservoir and can culminate with magma reaching the surface. After the magma propagation on 2 March, which did not end in an eruption, marked a change in the activity that had since December been somewhat cyclical.

If magma accumulation continues at a similar rate, the likelihood of another magma propagation increases in the coming days or weeks, even though an eruption is still ongoing. Magma propagation from the reservoir during an ongoing eruption has thus far not been seen before in the area. Therefore, more uncertainty is on the development of the activity in the next days or weeks.

Probable scenario if magma propagation coincides with the current eruption:

 

• Magma propagates from the magma reservoir beneath Svartsengi to the Sundhnúkur crater row, as has happened in the last six times.
• Following the magma propagation, new eruptive fissures could open in the area between Stóra-Skógfell and Hagafell and/or the current eruptive crater could be enlarged due to a sudden increase of lava flow. This could occur at very short or no notice.
• If magma propagation results in new volcanic fissures opening up elsewhere above the magma dike which formed on 10 November, much longer notice is expected, most likely intense seismic activity, deformation and pressure changes in boreholes.
• It is also possible that magma propagation will not occur, but that the flow of the current eruption will stop decreasing and begin to increase steadily until a new equilibrium between the inflow of magma from below and flow to the surface from the crater is reached.
• However, if magma propagation results in a new eruptive fissure opening elsewhere than in the area between Stóra-Skógfell and Hagafell, such a scenario would very likely be accompanied by intense seismicity and deformation with considerably more notice than previous eruptions.

Updated hazard assessment

In view of the uncertainty caused by increasing pressure in the magma reservoir beneath Svartsengi, the Icelandic Meteorological Office has increased the hazard due to possible opening of eruptive fissures in Zones 1, 4 and 7 from “low” to “considerable”

However, the overall hazard (color) in the affected Zones does not change.

(click on the image to see it larger)

 

Updated 18. April at 16:00 UTC

• The lava field now covers 6.15km² and the volume is 33.2 ± 0.8 million m³.

• Avegage lava flow from the crater over the period 8-15 April is estimated at 3.2 ± 0.2 m³/s.

• Ground uplift in Svartsengi continues at a steady rate.

• Continued hazard due to gas pollution. People in the area are advised to check the air quality.

• The weather forecast for gas distribution today (Thursday) is northwesterly wind, 3-8 m/s, carrying gas emissions to the southeast. Follow the gas dispersion forecast here.

 

The eruption at the Sundhnúkur crater row continues and one crater just east of Sundhnúkur remains erupting. The lava field continues to build up nead the craters. The lava also flows in closed channels about 1 km to the southeast and there are active areas in the lava field north of Hagafell.

On Monday 15 April, scientists from the Icelandic Institute of Natural History (IINH) and the National Land Survey of Iceland (NLSI) carried out a surrveillance flight over the eruptive area to aquire images for lava mapping by photo-grammetry. The results from the surrveilance flight show that the area of the lava field on the 15 April measured 6.15 km² and the volume 33.2 ± 0.8 million m³. The lava flow field and the thickness of it is shown on the map below.

Map showing the lava flow area and the thickness of the lava formed in the ongoing eruption. Purple colors show lava formed in the area since December 2023.

The average lava flow from the crater during the period 8-15 April is estimated at 3.2 ± 0.2 m³/s. This is a small change in relation to the average lava flow during the period 3-8 April, which was estimated at 3.6 ± 0.7 m³/s. The result of previous measurement by the IINH and NLSI photogrammetry team can be seen in the table below.

From	To	Average lava flow during period (m3/s)	Area   (km2)	Volume (million m3)	Average thickness of lava field (m)
16. mar.2024	17. mar.2024	234 ± 9	5,72	18,1 ± 0,8	3,2 ± 0,1
17. mar.2024	20. mar.2024	14,5 ± 0,6	5,58	20,9 ± 0,5	3,7 ± 0,1
20. mar.2024	27. mar.2024	7,8 ± 0,7	5,99	25,7 ± 1,9	4,3 ± 0,3
27. mar.2024	3. apr.2024	6,6 ± 0,3	6,13	29,7 ± 1,7	4,8 ± 0,3
3. apr.2024	8. apr.2024	3,6 ± 0,7	6,14	31,3 ± 2,4	5,1 ± 0,4
8. apr.2024	15. apr.2024	3,2 ± 0,2	6,15	33,2 ± 0,8	5,4 ± 0,1

 

 

Ground uplift in Svartsengi continues at a steady rate. This indicates that about half of the magma ascending from depth is accumulating in the magma reservoir, while the other half erupts to the surface at the Sundhnúkur crater row.

Displacements on the GPS station SENG in Svartsengi since 11 November 2024 to north, east  and vertical (top, middle, bottom). The bottom curve shows ground uplift in millimeters, and yesterday‘s (17 April) measurement is shown with a green dot. The red vertical lines are the timing of the last four eruptions (18 December 2023, 14 January, 8 February and 16 March 2024) and the blue lines show the magma dike intrusions that have occurred in the Sundhnúkur crater row area without resulting in an eruption (10 November 2023 and 2 March 2024).

There continues to be a hazard due to gas emissions from the eruption, which can cause pollution in settlements in the Reykjanes Peninsula, and we advise people in the area to monitor air quality and familiarise themselves with the response to air pollution from eruptions.

The weather forecast for gas distribution today (Thursday) is northwesterly wind, 3-8 m/s, carrying gas emissions to the southeast. Tomorrow (Friday) winds will be southeast 8-13 m/s with rain. More southerly winds in the evening. Gas pollution will go to the northwest during the day and later to the north. Follow the gas dispersion forecast here.

 

Updated April 16 at 18:00 UTC

• The hazard assessment has been updated. The overall hazard for Grindavík (Zone 4) is estimated to be considerable (orange).
• Land uplift at Svartsengi continues, and the rate of uplift has been consistent since the beginning of April.
• Continued hazard due to gas pollution. People in the area are advised to check the air quality.
• The gas dispersion forecast can be found here.
• One crater, located east of Sundhnúkur, remains active.

 

The eruption at Sundhnúkur crater row continues and has now lasted for one month, as was the subject of a news report published earlier today. One crater, which is located just east of Sundhnúkur, continues to erupt. Lava still flows to the south of the crater but does not extend far, so the lava field continues to build up near the crater. There is an active lava field near Hagafell, as can be seen in an image from the Icelandic Meteorological Office‘s webcam located at Þorbjörn.

Image from the Icelandic Meteorological Office’s webcam, taken at 5:10 AM, 16 April. The webcamera is located on top of Þorbjörn and looks east towards the eruption site. The crater is at the center of the image and lava flows from it. In front of the crater is Sundhnúkur, and on the right side of the image is Hagafell and lava flow fronts.

Seismic activity has been relatively calm near the eruption site since the beginning of the eruption until a small earthquake swarm began at Lágafell after noon on April 14. The seismic swarm lasted over 4 hours and has been associated with stress changes in the crust due to land uplift in Svartsengi. Seismic activity persists in the western slopes of Fagradalsfjall at 6-8 km depth and has been ongoing since the unrest in the Sundhnúkur area during the past 4 months.

Land uplift continues and has been at a steady rate since the beginning of April. Model calculations based on GPS data indicate that the inflow of magma into the magma reservoir is about half of what it was prior to the beginning of the eruption on March 16. This indicates that about half of the magma coming from depth is accumulating in the magma reservoir, while the other half is erupted to the surface.

At the beginning of April, the rate of land uplift started to increase. Currently, a similar volume of magma is erupting onto the surface and also accumulating in the magma chamber beneath Svartsengi, causing a pressure increase in the magma chamber.

There continues to be a risk of gas emissions from the eruption, which can cause air pollution in settlements on the Reykjanes Peninsula, and we advise people in the area to monitor air quality and familiarize themselves with symptoms and responses related to air pollution from the eruption.

The weather forecast today (Tuesday) is a slow wind, variable direction. Thus, gas may accumulate near the eruption site. Tonight, winds will be southeasterly 10-15 m/s, carrying gas emissions northwest towards Reykjanesbær. West and northwesterly winds are expected to be 3-10 m/s tomorrow morning, dispersing gas east and southeast towards Þorlákshöfn. Follow the gas dispersion forecast here.

Hazard assessment

The hazards assessment has been updated and is valid from 15:00 today until 23 April barring any developments. The hazards assessment has changed so that the hazard due to lava flows has been lowered in all areas except in Zone 3 (Sundhnúkur crater row) and Zone 6. This change is being made because there has not been an active lava flow in the other areas in the last two weeks. Based on current activity in the eruption, it is estimated that lava is unlikely to flow far from the crater and into other hazard Zones. This change means that the overall hazard in Zone 4 (Grindavík) is now assessed as considerable (orange) instead of high (red). The overall hazard in other areas remains unchanged. The hazard from gas emissions continues to be assessed as high in all areas except at the Sundhnúkur crater row area (Zone 3) where it is assessed to be very high. The hazard in Zone 4 (Grindavík) and Zone 6 continues to be assessed as high due to sinkholes and fault movements.

(Click on the image to see it larger)

 

Updated April 15 at 17:30 UTC

• The volcanic eruption that began on March 16 is still ongoing.

• Uplift continues at a similar rate since the start of April.

• The hazard assessment is valid until April 16, unless the situation changes.

• The risk of gas emissions remains significant. People in the area are reminded to monitor air quality.

• The gas dispersion forecast can be found here

 

Just after noon yesterday, a small earthquake swarm began near Lágafell, just northwest of Grindavík. It concluded around half past three in the afternoon. The swarm consisted of approximately 90 earthquakes, with the most intense period of activity being 35 earthquakes between 1 and 2 pm. All earthquakes were under magnitude 1, and most were at depths of approximately 2-4 km. This small earthquake swarm likely resulted from stress changes in the Earth’s crust due to ongoing land rise in Svartengi, as discussed in yesterday’s news update.

Attached is a figure showing the location of the earthquakes on a map, and below that is a graph showing their depth. The panel in the top right displays earthquake magnitudes in the region from noon until evening yesterday. The panel in the middle right shows the cumulative number of earthquakes, while the bottom panel displays the number of earthquakes per hour. As the graph shows, several small earthquakes were recorded in the area yesterday afternoon, but there hasn’t been any seismic activity in the region since midnight today.

Photograph taken on Wednesday, April 10, showing the active vent as seen from Sundhnúkur. (Photograph: Jón Bjarni Friðriksson/Icelandic Meteorological Office). Click on the image to see it larger.

 

Updated April 14 at 18:00 UTC

• The volcanic eruption that began on March 16 is still ongoing.

• Uplift continues at a similar rate since the start of April.

• The hazard assessment is valid until April 16, unless the situation changes.

• The risk of gas emissions remains significant. People in the area are reminded to monitor air quality.

• The gas dispersion forecast can be found here.

 

Several small earthquakes (below magnitude 1) have been detected northwest of Grindavík in the last few hours. (See figures below.) This seismic activity is focused near the dike that formed on November 10 and is likely related to the ground deformation in Svartsengi, which affects the region’s pressure regime.

Today’s seismic activity is comparable to the activity measured in this area in mid-March last year. Therefore, the seismic activity does not indicate any changes in the ongoing volcanic eruption, which has remained relatively stable over the weekend. The seismic activity northwest of Grindavík is also not indicative of magma moving beneath that area.

At the time of writing, the seismic activity northwest of Grindavík has slightly decreased. It is unlikely that large earthquakes will accompany this current activity.

Should magma deviate from its current route that surfaces at the Sundhnúkur crater row, opting instead for an alternate path, such as heading west towards Eldvörp or south of Þorbirnir, the precursor to a possible eruption in that area would involve very intense seismic activity and ground deformation that is clearly visible on instruments and satellite imagery. Currently, there are no such signs at this time.

The Icelandic Meteorological Office continues its 24-hour surveillance of the area to monitor the eruption site.

This figure displays seismic activity from March 9 until today, April 14. The black lines represent the outer boundaries of the grabens formed in connection with the significant dike intrusion on November 10, 2023, and the eruption on January 14 of this year. Most of the earthquakes today have been smaller than magnitude 1. Blue circles represent earthquakes that occurred from March 9 to 14, while red circles represent earthquakes that occurred today, April 14. The earthquakes are located on the western edge of the depression formed on November 10.

In the area northwest of Grindavík, there is a series of known faults with a north-south orientation that formed when the dike intrusion occurred on November 10. Therefore, today’s earthquakes are also indicative of stress release along these faults due to the land uplift in Svartsengi.

 

Updated April 12 at 14:15 UTC

• The volcanic eruption that began on March 16 is still ongoing.
• Land rise continues at a similar rate since the start of April.
• The hazard assessment is valid until April 16, unless the situation changes.
• The risk of gas emissions remains significant. People in the area are reminded to monitor air quality.
• The gas dispersion forecast can be found here .

The eruption that started at the Sundhnúkur crater row on the evening of March 16 is still ongoing. One vent remains active, as it has been since April 5. Lava continues to flow southward from the vent but does not travel far, so the lava field continues to build up near the crater. There are no apparent signs of lava advancing towards the protective barriers north of Grindavík, Suðurstrandarvegur, or Melhólsnáma.

Land rise in Svartsengi continues at a similar rate, which increased at the beginning of April. This is a faster rate than that observed from the start of the eruption on March 16 until the end of March. This indicates that the majority of the magma flowing into the reservoir beneath Svartsengi is accumulating there, causing an increase in pressure and ground uplift. While the eruption continues, there remains an open connection between the magma accumulation area in Svartsengi and the Sundhnúkur crater row, and a portion of the magma continues to flow to the surface there. Minor changes in the lava field can be observed between days, but the overall rate has been steady since the beginning of April.

The hazard assessment remains unchanged and valid until 15:00 on April 16. See more details here.

There is still a risk of gas emissions from the volcano, which could cause pollution on the Reykjanes Peninsula. People in the area are advised to monitor air quality and familiarize themselves with symptoms of exposure to volcanic gas pollution.

A photograph taken on Wednesday, April 10th, showing the active crater as seen from Sundhnúkur. (Photo: Jón Bjarni Friðriksson)

Updated 9. April at 17:30 UTC

• Despite a decrease in the intensity of the volcanic eruption, there are no signs that the overall magma flow from the depth is decreasing.

• The average flow rate of the lava flow from the vents between April 3rd and 8th is estimated to be 3.6 ± 0.7 m3/s.

• Tomorrow, easterly and southeasterly winds are expected, carrying gas emissions westward and northwestward from the eruption sites. Follow the gas dispersion forecast here.

• Periodically high levels of SO2 continue to be measured around the volcano and in settlements on the Reykjanes Peninsula. Residents are advised to monitor air quality in the area.

Experts from the Icelandic Meteorological Office and the National Land Survey conducted aerial measurements over the eruption site yesterday, April 8th. Using the data collected during the flight, it is possible to assess the size of the lava field and the flow rate of lava from the eruption. The results indicate a steady and substantial decrease in the intensity of the volcanic eruption.

The average lava flow from the vents between April 3rd and 8th is estimated to be 3.6 ± 0.7 m3/s. Based on data collected by the engineering firm Efla on April 3rd during a drone flight, the average lava flow was estimated to be 6.6 ± 0.3 m3/s from March 27th to April 3rd. The lava field has reached an area of 6.14 km2 with a volume of 31.3 million m3. Previously, the lava primarily flowed south from the vents, but briefly shifted northward on Sunday evening (April 7th) when a vent wall collapsed, as mentioned in the last update. As shown on the accompanying map, the lava has thickened significantly near the vents and just south of them, where the most activity is in the lava field. There are no apparent signs of lava advancement toward protective barriers north of Grindavík, Suðurstrandarvegur, or Melhólsnáma.

Map showing the extent and thickness of the lava formed in the current eruption. Purple areas show lava that has flowed in the area since December 2023.

Ground deformation has increased over the past week

Ground deformation in Svartsengi continues to increase, coinciding with a decrease in the intensity of the volcanic eruption. This indicates that the majority of the magma flowing into the reservoir beneath Svartsengi is accumulating there, causing an increase in pressure and ground uplift. While the eruption continues, there remains an open connection between the magma accumulation area in Svartsengi and the Sundhnúkur crater row, and a portion of the magma continues to flow to the surface there.

Seismic activity in the dike near Grindavík has remained very low and is focused between Sýlingarfell and Stóra-Skógafell, with slight seismicity in western Grindavík. Seismic activity near Fagradalsfjall, which has been persistent for the past month, is ongoing and remains localized at depths of about 6-7 km.

Gas measurements conducted yesterday, April 8th, estimate a sulfur dioxide (SO2) emission rate of 10-18 kg/s from the vents. Periodically high levels of SO2 continue to be measured around the volcano and in settlements on the Reykjanes Peninsula. Gas emissions from the eruption will likely cause pollution on the Reykjanes Peninsula, and residents are advised to monitor air quality and familiarize themselves with symptoms related to air pollution from the eruption.

According to the weather forecast, northerly winds are expected today, carrying gas emissions southward. Slow variable winds in the afternoon may result in gas pollution near the eruption sites. Easterly and southeasterly winds are expected tomorrow, carrying gas emissions westward and northwestward. Follow the gas dispersion forecast here.

Unchanged risk assessment

The hazard assessment has been updated and is valid from 15:00 today until April 16th, unless the situation changes. There are no changes in the hazard assessment, and the risk of gas pollution remains high in all areas except around the Sundhnúkur crater row (Zone 3), where it is assessed to be very high. The risk in Zone 4 (Grindavík) and Zone 6 remains high due to earthquakes, ground deformation, lava flows, and gas pollution.

(Click on the image to see it larger)

Despite the decrease in the intensity of the volcanic eruption, there are no signs that the overall magma flow from depth into the Svartsengi reservoir is decreasing. This refers to the total volume of magma accumulating under Svartsengi, in addition to the magma flowing towards the surface in the current eruption at the Sundhnúkur crater row. It is difficult to predict when this eruption will end; it could continue for a longer period with steady flow or cease in the near future. As magma continues to accumulate under Svartsengi and pressure rises, a possibility remains that the eruption’s intensity may increase again, similar to the events at Fagradalsfjall in 2021. If the eruption ceases soon, magma accumulation will likely continue under Svartsengi, and a sequence of events similar to that observed in the past month may repeat.

Updated 8. April at 16:30 UTC

• The volcanic eruption continues. One vent is active.
• The land has risen in Svartsengi approximately 2-3 cm between April 2nd and 7th.
• Minimal gas emissions were measured over the weekend, but periodically high levels of sulfur dioxide can still be detected around the volcano and in settlements on the Reykjanes Peninsula. Residents are advised to monitor air quality in the area.
• Today’s weather forecast indicates a northeasterly wind direction, causing gas emissions to drift southwestward over areas including Grindavík. Easterly winds are expected tomorrow, April 9th, and gas emissions are anticipated to travel west from the eruption sites. Follow the gas dispersion forecast here.

The eruption at the Sundhnúkur crater row continues, with one vent now active. Yesterday, lava from the vent flowed southward in a constrained stream, resulting in a magnificent river of lava. Meanwhile, the surface level of lava in the crater gradually increased until it was nearly filled. The northern wall of the vent collapsed around 21:30 yesterday evening, causing the lava to flow northward. Today, April 8th, the lava flow has mostly resumed its southward direction. The lava advancing towards the north, as observed yesterday evening and overnight, appears to have halted on the hillside. The crater continues to fill up.

Seismic measurements near the eruption site show volcanic tremor that exhibits strong frequencies between 1 and 2 Hz (green curve on the graph); an increase in the strength of this tremor corresponds with the peak flow of lava from the vent. After the collapse of the vent wall, seismic activity appears to decrease again. Similar seismic activity was observed during the recent Geldingadalur volcanic eruption, during which seismic activity increased as the output of lava intensified.

Uplift has slightly increased in Svartsengi, and based on GPS measurements and synthetic aperture radar images, the land has risen by 2-3 cm from April 2nd to 7th. However, this is less than the ground deformation measured after the previous eruption last month. Increased uplift could indicate that magma flowing into Svartsengi has increased or that there has been a slowdown in the flow of magma towards the current eruption site.

Minimal gas emissions have been detected on gas monitors operated by the Environment Agency of Iceland (UST) and the Icelandic Meteorological Office over the weekend, but periodically high levels of sulfur dioxide can still be detected around the volcano and in settlements on the Reykjanes Peninsula. Residents are reminded to monitor air quality on the UST air quality website loftgæði.is

Today’s weather forecast indicates a northeasterly wind direction, causing gas emissions to drift southwestward over areas including Grindavík. Easterly winds are expected tomorrow, April 9^th, so gas emissions can be anticipated to drift west from the eruption sites. The latest gas dispersion forecast can be followed here.

Updated 4. April at 17:00 UTC

The eruption at the Sundhnúkur crater row continues and two craters are still active as in recent days. The northern crater is larger and most of the lava flow seems to be erupted from it, as can be seen in the image below which was taken last night, 3 April. Lava continues to flow south from the craters on top of the lava field formed in the first few days of this eruption. Last night there no clear signs of lava flow progressing alongside the lava barriers north of Grindavík, Southcoast road or Melhólsnáma mine.

Aerial image from a drone flight operated by Civil Protection last night, 3 April. The image shows the two craters and the lava flowing from them towards the south.

An interferogram covering the period 18 March – 3 April shows that land has risen about 3 cm in Svartsengi during that time. This is considerably slower deformation that was measured prior to the eruptions and dike propagations which have occurred in last months. Data from GPS measurements during the same period suggests that the rate of the land uplift has varied, but it difficult to estimate day-to-day deformation based on this data. Considering the GPS data for the same time period as the interferogram (18March – 3 April), the two datasets are consistent. Land uplift is detected in Svartsengi during the eruption, which has not been seen in the events that have occurred previously on the Sundhnúkur crater row.  This indicates that the system is open, and magma continues to flow from considerable depth below Svartsengi to the surface in the Sundhnúkur crater row. 

Interferogram (InSAR) showing deformation from 18 March – 3 April. Yellow and orange colors show areas around Svartsengi where land uplift is detected.

Gas measurements carried out last Tuesday, 2 April, estimate that approx. 37-41 kg/s of SO₂ is emitted from the craters. Temporary high sulfur dioxide levels continue to be measured around the eruption site and in municipalities in the Reykjanes peninsula. Gas from the eruption is likely to cause pollution in the Reykjanes peninsula and we advise people in the area to monitor air quality at loftgaedi.is and familiarize themselves with the response to air pollution from volcanic eruptions.

The weather forecast today (Thursday) is southeast and southerly winds of 8-13 m/s at the eruption site, causing gas to be dispersed to the northwest and north, meaning gas could be detected in Vogar, Reykjanesbær and Suðurnesjabær. Easterly winds 5-10 m/s tomorrow (Friday), causing gas dispersion towards the west, for example to Svartsengi. Northesterly winds, 5-10 m/s late tomorrow causing gas pollution in the southwest and possibly in Grindavík.

Gas distribution forecast is here.

Hazard assessment published on 2 April remains unchanged and is valid until 9 April barring any developments.

Updated 2. April at 17:30 UTC

• The eruption continues and two craters are now active. Inflation hasn‘t been detected in the last few days.

• Lately, vegetation fires have started around the lava field, and is an ongoing risk while the weather is dry.

• Gas pollution is dispersed to the southwest and later to the west and is likely to be detected occasionally in Grindavík and possibly in Hafnir. Gas distribution forecast and air quality can be monitored.

• Lava margins have reached considerable heights and can be unstable.

• Hazard assessment unchanged.

 

The eruption at the Sundhnúkur crater row continues and two craters are now active. The third crater, which was much smaller than the other two, was extinguished at Easter. Volcanic tremor remains stable.

Inflation in Svartsengi has not been detected in recent days, indicating that less magma accumulates in the magma reservoir beneath Svartsengi, and flows instead towards the craters where it erupts. A balance may be reached between the influx of magma into the Svartsengi reservoir and the eruptive craters, but geochemical surveys might confirm this in the future.

Experts from the National Land Survey of Iceland have processed satellite data from 27 March showing that the lava field was then 5.99 km2 and the volume of lava since the beginning of the eruption was 25.7 ± 1.9 million m3. The average extrusive rate of lava from the craters was estimated at 7.8 ± 0.7 m3/s, which is very comparable to the extrusion rate during the first phase of the Geldingadalir eruption in 2021. The aim is to take aerial photographs of the area in the coming days to get updated extrusion rates since 27 March, which will give further insights into the development of the eruptive activity. The following map shows the lava flow field and its thickness as it was on 27 March.

Map showing the flow field and thickness of the lava formed during the ongoing eruption. Purple layers show lavas that have formed in the area since December 2023.

Vegetation fires around the lava field

Lately, vegetation fires have started around the lava field, and is an ongoing risk while the weather is dry.

Lava margins have reached considerable heights and can be unstable, sudden and rapid lava outbursts can occur if new lobes of lava break out from the edge of a lava margin.

In recent days, high levels of hydrogen sulfide have occasionally been detected in Grindavík. The weather forecast today (Tuesday) is northeasterly and later easterly winds 5-13 m/s at the eruption site. Gas pollution is therefore dispersed to the southwest and later to the west, and is likely to be detected occasionally in Grindavík and possibly in Hafnir. Easterly and southeasterly winds 3-10 m/s tomorrow (Wednesday) causing gas pollution to travel to the west and northwest, and thus could be detected in many parts of the western Reykjanes area, including Reykjanesbær. Gas distribution forecast is here.

Hazard assessment unchanged

The hazard assessment has been updated and is valid from 15:00 today until 9 April, barring any significant developments. There are no changes to the hazard assessment and the hazard from gas pollution continues to be assessed high in all areas except at the Sundhnúkur crater row area (zone 3) where it is assessed as very high. The hazard in zone 4 (Grindavík) and zone 6 continues to be assessed as high due to sinkholes, fault movements, lava flow and gas pollution.

 

Updated 27. March at 14:00 UTC

 

• High levels of SO₂ (Sulfur Dioxide) were measured over the weekend. Gas dispersion forecast can be followed here .
• This concentration of SO₂ is considered very unhealthy. It is important to pay close attention to developments in air quality.
• The volcanic eruption has been stable since Monday, 25. March.
  

 

 

The volcanic eruption has been stable since Monday, 25 March. Eruption tremor has remained consistent since then, as has the activity in the three craters. Lava continues to flow southward from the craters mostly atop the lava field formed during the first days of the eruption. The following image shows the extension of the lava field as extrapolated from satellite images (ICEYE). The latest acquisition was on 26 March and it shows the widening of lava field towards the west, south of Hagafell, as well as further lava advancement towards the east and the south of the active vents.

Striped areas indicate regions where changes occurred in the lava field between March 20 and 26. The red-striped part of the area signifies area where lava had not flowed previously in this eruption. Light purple areas denote areas where lava flowed from eruptions in February and January.

Uplift continues in Svartsengi but at a slower rate than prior to previous eruptions or dike intrusions in recent months. This suggests that magma is still accumulating beneath Svartsengi despite ongoing eruption. Little to no seismic activity has been detected in the area.

 

High levels of SO2 measured past few days

 

Since friday (22 mars) two additional stations to monitor the concentrations of SO2 at the ground have been installed. VÍ, in collaboration with Almannavarnir, located them at Blue Lagoon and in the harbour area in Grindavík. Both stations are streaming data to the UST website, loftgæði.is.

Early yesterday morning, at around 03:00, the station in BL revealed levels of SO2 up to 7000 microgram/m3, and this morning at around 04:00 the station in Grindavík (Nesvegur) measured concentrations up to 9000 micrograms/m3. Such concentrations are considered óholl and people are recommended to follow the instructions provided by UST and Embætti landlæknis (link). On the 26^th March, the station in Hafnir also showed high concentrations of SO2 up to about 2000 microgarm/m3 around midday. The amount of SO2 released by the eruption and the meteorology in the area are still creating the conditions for severe gas pollution in the peninsula.

Photo since this morning (27. March) from IMO’s webcam located at Hópsnes SE of Grindavík. In the center of the photo is Mt. Þorbjörn and the eruption site east of it where the gas plume rises and moves to the west because of easterly winds.

 

Updated 25. March at 16:30 UTC

• High levels of SO₂ (Sulfur Dioxide) were measured over the weekend. Gas dispersion forecast can be followed here .
• This concentration of SO₂ is considered very unhealthy. It is important to pay close attention to developments in air quality.
• Volcanic activity appears to have decreased at Sundhnúksgíga.
• The hazard assessment remains unchanged. Increased hazards persist due to gas emissions

 

Volcanic activity at Sundhnúksgíga appears to have decreased over the past few days. Activity in the vents has decreased and possibly ceased in the smallest craters. Additionally, volcanic tremor has gradually diminished over the past few days. The main lava flow runs southward from the vents and then bends westward. Over the weekend, lava continued to flow into Melhólsnáma and has now filled it. However, the lava also continues to thicken near the craters.

GPS measurements in recent days indicate ongoing land rise in Svartsengi, but it exhibits a slower rate than before. This suggests that magma continues to accumulate in the reservoir beneath Svartsengi despite the ongoing eruption.

High levels of SO2 measured past few days

High levels of SO₂ have been measured in Höfn and Grindavík the past few days. This concentration is considered very unhealthy, and people are likely to experience respiratory symptoms if exposed. It is important to stay indoors, close windows, and turn off air conditioning. This is especially important where outdoor work is being carried out, as stated by the work safety authorities; companies and institutions in the southwest region of the country must pay close attention to further developments in air quality due to the potential risk of gas pollution. People in the area are advised to monitor air quality and familiarize themselves with symptoms of air pollution from volcanic gases.

The weather forecast for today (Monday) predicts northeasterly winds of 3-8 m/s at the eruption sites, with the pollution drifting southwestward (over Grindavík and Svartsengi); gas may accumulate near the eruption sites due to slow wind speeds. In the evening, night, and early morning hours, winds are expected to come from the east at 8-13 m/s at the eruption sites, causing pollution to drift westward, towards areas including Hafnir. During this period, it’s also possible that the wind may become southeasterly at times, potentially causing pollution in Njarðvík, Keflavík, and Sandgerði. By late afternoon tomorrow (Tuesday), winds will shift to be northeasterly at 3-8 m/s, causing the gas pollution to drift southwestward (over Grindavík and Svartsengi) and possibly to accumulate near the eruption sites due to light winds. The gas dispersion forecast can be found here.

No changes in the hazard assessment

The hazard assessment has been updated and is valid from 15:00 today until April 2, barring any significant developments. There are no changes in the hazard assessment, and the risk of gas pollution remains high in all areas except for the Sundhnúksgíga crater row (Area 3), where it is assessed to be very high. The hazard in Area 4 (Grindavík) remains high due to fault movements, sinkholes above fissures, lava flows, and gas pollution.

(Click on the map to see it larger)

 

Updated 22. March at 17:20 UTC

• Updated hazard assessment.
  
• Increased risk due to gas emission. Gas dispersion forecast here
  
• Volcanis activity at the eruption site stable

 

Volcanic activity at the eruption sites near Sundhnúkur remains stable. There is little to no earthquake activity in the dike or its vicinity. Land uplift in the area around Svartsengi has been very slight since the dike intrusion and subsequent eruption began on March 16. This suggests that less magma is accumulating beneath Svartsengi and is instead flowing more directly out of the reservoir through the eruptive fissures. However, there may be indications that uplift has increased in Svartsengi since then, but it cannot be confirmed at this point. Measurements in the coming days will shed more light on this development.

Today’s (Friday’s) weather forecast includes north to northwesterly winds at around 8-15 m/s, shifting to a more northeasterly direction in the evening with somewhat lower speeds, and gentler northeasterly winds tomorrow morning. Gas emissions will mostly be directed south of the eruption sites towards Grindavík. Gas dispersion forecasts can be found here.

Increased hazards due to gas emissions

The hazard assessment has been updated and is valid from 15:00 today, Friday, March 22, until 15:00 on Monday, March 25. The risk due to gas emissions is assessed to be higher within all regions compared to the previous days. This is due to the unfavorable weather forecast for the next few days and higher measured values of sulfur dioxide (SO2) emissions from the eruption sites and the lava field than before. In areas 1 and 5 (northwest of the eruption sites), the risk of lava flows is lower than it was in the past three days. This risk has decreased because the lava flow north of the eruption sites has stabilized, and lava is now preferentially flowing to the south. However, the lava field remains hazardous because it formed very recently.

(Click on the map to view it larger)

 

Updated 21. March at 11:40 UTC

• Average discharge rate for 17 – 20 March is 14.5 m³/s   

• The new lava now covers an area of 5.58 km² and has a volume of 20.9 million cubic meters.

• Accumulation of magma below Svartsengi seems to have stopped and instead magma flows directly to the surface and feeds the eruption.  

• Minor deformation has been measured in the Svartsengi area and in the proximity of the dyke intrusion.

 

The eruptive activity appears to have been relatively stable the last 24 hours. The same vents seem to be active, and craters continue to build up around the vents. Lava flows towards the south from the craters in an active lava stream, both on the surface and below the solidified surface of the lava.

Overview of the eruption site taken on a flight yesterday morning 20 March at 9am. It shows all the active volcanic vents.

Yesterday morning experts from the National Land Survey of Iceland and the Institute of Natural History conducted aerial photography flights over the eruption site. From these images it is estimated that over the period from 17-20 March the average discharge rate of the eruption is 14.5 m3/s. This is similar discharge rate as observed during the eruptions in Fagradalsfjall 2021-2023. However, the discharge rate during the first 24 hours of the eruption was significantly higher. The area of the new lava field was measured 5.58 km2 and the volume 20.9 million cubic meters. The map below shows the extent and thickness of the new lava as measured yesterday morning, 20 March. The lava is 16 m thick where its thickest by the craters.

Map showing the extent of the newly erupted lava. Violet layers show the older lava that erupted in December 2023, January 2024 and February 2024.

Very little deformation has been measured in the Svartsengi area and in proximity of the dyke formation. Any measured deformation is so small that variability between days is inconsiderable. Several more datapoints are needed to infer if any uplift continues in the area. It can though be determined that magma flows now directly to the surface, feeding the eruption.

The weather forecast today for the area is north and north-westerly winds, 8-15 m/s, gas pollution is dispersed to the east and south-east and could be felt in South Iceland, for example in Þorlákshöfn and in Vestmannaeyjar. A more northerly wind tomorrow (Friday), causing gas pollution to be dispersed to the south and south-east and could be felt in and around Grindavík.

 

Updated 20. March at 13:45 UTC

 

The eruptive activity appears to be relatively stable and eruptive vents remain in the same locations as yesterday. Lava flows from the craters towards the south, on top of lava which flowed in the first days of the eruption. Little or no movement has been detected on the lava flow fronts near the South Coast Road and Svartsengi. Seismic activity since the eruption began on Saturday night has been minor.

The weather forecast is increasing south-easterly winds today, 13-20 m/s in the afternoon, but subsides in the evenings. Gas pollution is thus dispersed to the north-west and could be detected in Reykjanesbær and nearby areas. Gas distribution forecast can be found here. On 17 March, SO₂ gas emission from the eruption was measured up to 50 kg/s, but preliminary results from new measurements indicate that the emission of gas has decreased considerably since then.  

An InSAR image published yesterday showed clear signs of land inflation in Svartsengi from 17 to 18 March. GPS data from 18 March suggest that the inflation rate is possibly decreasing. This could be due to magma now flowing towards the surface in the Sundhnúkur crater row and therefore does not accumulate beneath Svartsengi. The development of the eruption and deformation signals over the next few days will reveal whether an equilibrium will be reached between the magma inflow beneath Svartsengi and the lava flow on the surface in the Sundhnúkur crater row.

This morning, experts from the National Land Survey of Iceland and the Institute of Natural History conducted aerial photography flights over the eruption site. From these images it is possible to estimate the size of the lava field and the average lava flow from the eruption. There estimates will be published as soon as the data have been processed.

Figure caption: Overview of the eruption site taken on a flight this morning. It shows all the active volcanic vents and flava flows from them to the south. In the background to the left is Grindavík and to the right is Svartsengi. (Image: Birgir V. Óskarsson – Institute of Natural History).

 

Updated Hazard Map

The Icelandic Meteorological Office has updated its hazard assessment in light of the latest data. The new hazard assessment takes effect today, Wednesday, March 20, and is valid until March 22, unless the situation changes. Zone 3 (the Sundhnúkur crater row), where the eruption is still ongoing, remains unchanged, and the danger is considered very high. The danger in zone 1 (Svartsengi) is now considered considerable, whereas it was previously considered high. The danger in zone 4 (Grindavík) remains high as the risk due to sinkholes, fault movements and lava flow is considered high. In zone 3 (the Sundhnúkur crater row), the risk due to gas pollution is considered very high, but in all other areas, the risk of gas pollution is now considered considerable, whereas it was previously high. This change is due to lower gas emissions from the eruption than at the beginning. The danger due to gas pollution and ash is also assessed based on the weather and dispersion forecast for the next few days, which affects their spread.

(Click on the map to see it larger)

Updated 19. March at 17:30 UTC

• The eruption continues and has been ongoing since 16 March at 20:23 UTC.
• Volcanic tremor is detected and has remained relatively stable for the past two days which indicates that the eruption‘s vigour has not decreased.
• Inflation continues in Svartsengi, suggesting that magma is still ascending from depth into the magma reservoir beneath Svartsengi as well as flowing towards the eruptive site.
• The hazard assessment map which was updated yesterday (18 March) is unchanged.

The eruption continues and has now lasted for over two and a half days, which is longer than the previous three eruptions that have occurred in the area since December 2023. The eruptive activity is in the same places as yesterday afternoon, on the southern part of the volcanic fissure. Crater rims continue to build up and lava fountaining is still considerable. The lava flow front, which was approximately 300 m from the South Coast Road yesterday, does not appear to have moved forward. Lava flow from the craters remains mostly to the south, with active lava flow fronts on top of the lava that flowed at the beginning of the eruption.

Seismic activity has been negligible at the dike area since the eruption started, but volcanic tremor is detected and has remained relatively stable over the past two days, an indication that the eruption’s vigour has not decreased.

When magma propagated from Svartsengi towards the Sundhnúkur crater row on the evening of 16 March, land subsidence was detected in Svartsengi, as when previous magma dike formed. GPS data and satellite images received after the magma propagation show that surface inflation continues in Svartsengi, suggesting that magma is still ascending from depth into the magma reservoir beneath Svartsengi as well as feeding the eruption.

It should be noted that relatively few data points have still been obtained in the short time since the eruption began and that the data is always subject to uncertainty. Deformation data, which will be available in the next few days, will allow experts to further estimate using model calculations the amount of magma flowing in under Svartsengi.

InSAR image showing measured inflation (red areas) between 17 and 18 March after the eruption began. The image is based on data from the ICEYE satellite

According to measurements carried out last night, the outflow of gas from the eruption has decreased compared to what it was at the beginning of the eruption. However, it is still likely that gas pollution will be detected, and the weather forecast indicates increasing south-westerly winds, around 13-20 m/s at the eruption site today, but winds will decrease this evening. Gas pollution is thus directed to the north-east. See gas distribution forecast here.

The hazard assessment map updated yesterday remains unchanged until 15:00 tomorrow 20 March, barring any changes to the situation.

Updataed 18. March at 18:30 UTC

 

The Icelandic Meteorological Office has updated the hazard assessment to account for the latest data. The new hazard assessment takes effect today, Monday, March 18, and is valid until March 20, unless the situation changes. Zone 3 (the Sundhnúkur crater row), where the volcanic eruption is still ongoing, remains unchanged, with the hazard level remaining very high. The hazard level is assessed to remain high in Zone 1 (Svartsengi) due to gas emissions and lava flows. The same applies to Zone 4 (Grindavík), where the danger due to sinkholes above fissures, fault movements, lava flows, and gas emissions is considered high. Zone 5 has been downgraded to considerable risk (orange) and Zone 7 is now downgraded to some risk.

The reason for assessing the danger as greater in Zone 1 than in Zone 5 is the closer distance to the active end of the eruptive fissure. The weather forecast and gas dispersion forecast for the next few days will affect the assessment of gas pollution and ash in the hazard assessment.

 

Updated 18. March at 16:50 UTC

• The volcanic eruption’s activity has been relatively stable since late yesterday.
• There is a very slow movement of the lava flow towards the road Suðurstrandarvegur.
• This morning, the lava flow was approximately 330 meters from the road. The margin has not advanced significantly since yesterday evening.

 

Eruptive activity has been relatively stable since yesterday afternoon. The eruption is focused at two locations along the eruptive fissure, but the northernmost craters that were active yesterday are not active now. The most active areas are near the southern end of eruptive fissure that opened on Saturday evening, with lava flowing from these locations southward towards the road Suðurstrandarvegur. This morning, the lava flow was approximately 330 meters from the road, with minor movement of the margin since yesterday evening. Observations of the area yesterday evening indicate that there is not significant activity or movement of the lava flow that crossed the road Grindavíkurvegur few hours after the eruption started.

 

The extent of the new lava is estimated to be 5.85 square kilometers, based on satellite imagery acquired at 14:56 yesterday, March 17. See the accompanying map. This area estimation, based on satellite data, contains greater uncertainty than calculations based on aerial photographs. If weather conditions allow, an aerial survey of the eruption site will be conducted later today, providing more accurate calculations of the area and volume of lava.

 

The outlines of the lava flow are drawn from satellite images from Iceye. The first image was taken on March 17 at 01:55 (orange color), which is about five and a half hours after the eruption began. The second image was taken at 14:56 on March 17, showing the outlines of the lava, as it was then, shown in red. Purple colors indicate lava flows from previous eruptions.

The weather forecast for later today brings wind from the southeast and east with a speed of 8-13 m/s at the eruption site, followed by decreasing winds from the south and southwest. Gas emissions will therefore drift northwest and west, with a shift to the north later today. Significant uncertainty exists in the strength of gas emissions. Wind from the southwest with a speed of 10-18 m/s is expected tomorrow morning, so the gas emissions will then travel to the northeast. It is unlikely that gas emissions will reach the Capital Region due to strong winds. The gas dispersion forecast can be monitored here.

There is minor seismic activity near the eruption site and throughout the Reykjanes Peninsula. Only a handful of small earthquakes have been observed. The risk assessment will be updated later today.

 

Updated 17. March at 18:40 UTC

 

Since 04:00 UTC today, the propagation of lava has slowed substantially. However, the eruption has not ended, and lava continues to be extruded from a 0.5-km-long fissure, as confirmed by web camera and drone imagery. A lava front extends to the west from Sundhnúkur crater row. This front inundated Grindavíkurvegur in the early hours of Sunday morning at around 00:30 UTC, making the road impassable.

Lava also travelled southwards, and it is now less than 250 m from Suðurstrandarvegur – the main road on the southern coast of the Reykjanes Peninsula. Between 10:15 and 16:30 UTC today, this lava front moved at an average speed of 12 m per hour. Assuming the same speed of movement, it will take the front an additional ~20 hours to reach the main road. In the event of the lava reaching the road, an additional 350 m of propagation would be needed before lava could enter the sea.

Below is a map showing the impact area if the lava were to reach the sea. This scenario and response plans related to it have been discussed at status meetings of the Meteorological Office and Civil Protection yesterday and today.

In the event of lava interacting with seawater, there would be a range of volcanic hazards due to the sudden cooling of lava. Initially, these hazards would comprise localised tephra deposition (solid volcanic particles) and the formation of volcanic gases, principally hydrogen chloride (HCl). Within a radius of 0.5 km from the entry point into the sea, there would be potentially lethal health hazards. With increasing distance, the severity of the volcanic hazards decreases over a radius of 3 km. Beyond that distance, health hazards due to gas pollution would be minor in nature.

Based on the development of the eruption today, our assessment is that lava flow into the sea is an unlikely scenario. However, until the eruption ends, and lava propagation stops entirely, it remains an outcome to consider for hazard assessment purposes. Assuming the same speed of movement (12 m per hour), it would take the southern lava front two days to reach the coastline.

 

Updated 17. March at 13:00 UTC

The volcanic eruption that began at 20:23 last night continues, but during the night the intensity of the eruption decreased, and now there are three active openings on the eruptive fissure. Seismic activity also significantly decreased overnight, with very few earthquakes measured after 3:00, coinciding with a decrease in volcanic tremor. This development is very similar to the three previous eruptions on the Sundhnúkur crater row.

Shortly after midnight, lava flowed over the Grindavík road towards the water distribution pipe from Svartsengi power plant. There has been limited advancement in that lava flow front since this morning and it is now about 200 meters from the pipe. Another lava flow front runs alongside the protective barriers east of Grindavík and towards Suðurstrandarvegur road. Response workers in the area are monitoring the lava’s advance rate, which has been slow and steady since this morning.

The eruption fissure as it was at 11:00 today. To the right of the image is Mt. Stóra-Skógafell, and to the left is Mt. Sýlingarfell. The most active part of the fissure is east of Sýlingarfell, with smaller openings to the north.

Today’s weather forecast is northeast winds of 8-13 m/s with intermittent rain, but the wind will gradually decrease. Gas emissions will mainly drift southwest from the eruption site. Tomorrow, southeast winds of 8-13 m/s are expected with showers, and the gas emissions will likely drift northwest. Temperatures generally range from 1 to 5 degrees Celsius near the eruption sites. There is considerable uncertainty regarding the intensity of gas emissions. See the gas dispersion forecast here.

 

Updated 17. March at 01:25 UTC

 

The Icelandic Met Office has updated the hazard map for the area. Lava flow continues to the south and southeast. The speed of the lava front is estimated to be 1 km/hr.

If the eruption continues at the same rate the scenario of lava reaching the ocean needs to be considered.

Now, about five hours into the eruption, the activity has been fairly constant for the whole length of the fissure.

 

Updated 16. March at 23:50 UTC

 

A volcanic eruption has begun between Mt. Hagafell and Mt. Stóra Skógfell. The eruption began at 20:23 UTC on 16 March, with a 2.9-km-long fissure forming quickly. The length and location of the fissure is similar to the eruption on 8 February 2024.

The pre-eruptive warning phase was very short. The first warning to the Department of Civil Protection and Emergency Management was at 19:43 UTC, and the onset of eruption was confirmed on web cameras just 40 minutes later. The eruption is effusive in nature, so the eruption plume consists mainly of steam and gas.

Picture showing the status of the eruption at 21:40. (Photo: DCPEM/Björn Oddsson)

The Icelandic Coast Guard performed a helicopter flight over the eruption area. The flight had experts from IMO, the University of Iceland, the Department of Civil Protection and Emergency Management. Lava is flowing westwards from the eruption fissure in the direction of Grindavíkurvegur (road) and the protection barriers for the Svartsengi region. Additionally, a large lobe of lava is flowing southeast, towards the protection barriers for Grindavík.

The map shows the fissure opening in red. Orange lines shows lava barriers.

From initial assessments of web camera imagery and aerial photographs from the helicopter flight, the eruption is thought to be the largest (in terms of magma discharge) of the three previous fissure eruptions from the Sundhnúkur crater row. This estimate applies to the first hour of eruptive activity.

At 22:10 UTC, the southern lava front was just 200 m from the barriers on the eastern side of Grindavík and moving at a rate of about 1 km per hour. At 22:20 UTC, lava was 700 to 800 m away from Grindavíkurvegur, nothwest of Grindavík, moving at a rate of approximately 1 km in 1.5 hours.

Updated 15. March at 14:30 UTC

 

Higher uncertainty than before about the timing of the next dike intrusion and possible eruption.

GNSS displacements and recent interferograms show continued inflation of the Svartsengi magma reservoir – at a similar rate to that observed prior to the diking event on 2 March 2024. Geodetic modelling using these datasets confirms the inflation source is also at a similar location and depth as that observed during previous inflation episodes.

The models inditate a recharge volume of approx. 4 million cubic meters to the Svartsengi reservoir since 3 March.

For the diking events that occurred between 14 January to 2 March, the failure limit calculated to trigger these dike intrusions and/or eruptions was consistently estimated at around 10 million cubic meters. This enabled longer-term forecasts to be made based on the volume loss from the magma reservoir during the diking events and then estimating the time window when this amount would be fully recharged, hence triggering the next event.

However, on 2 March it is estimated that a much smaller volume was lost from the magma reservoir during this event (approx. 1.3 million m3) which triggered a small dike intrusion that did not result in an eruption.

A larger volume, compared to the amount lost from the Svartsengi reservoir on the 2 March, has now been recharged, yet a new dike intrusion/eruption has not yet occurred. This indicates a possible change in the magma plumbing system and greater uncertainty in the new failure limit that now needs to be reached, and thus the timing, of the next dike intrusion and/or eruption.

When this new limit is reached, the most likely scenario is another dike intrusion within the existing diking area – between Stóra-Skogfell to Grindavík – which may or may not culminate in an eruption.

Seismicity NW of Grindavík not a sign of dike intrusion there

We cannot rule out the possibility of an eruption occurring within an adjacent area or volcanic system e.g. west of Mt Þorbjörn or in Eldvörp, however, prior to this occurring a new dike will first need to be intruded in the corresponding area.

There is currently no evidence of a dike intrusion within these areas. Such an intrusion in a new area, is expected to be characterised by a strong earthquake sequence, and large amounts of ground deformation detected on both the GNSS network and on interferograms – none of these monitoring datasets currently show any evidence of this.

There has been an increase in seismicity (all earthquakes < M1.5) to the north west of Grindavík. It is likely that the continued inflation of the Svartsengi magma reservoir is now triggering small movements on pre-existing faults in this area that were activated during the 10 November 2023 diking event.

The map shows seismicity detected from 3 March to 14 March. Black lines outline Grabens that formed in diking events on 10 November 2023 and 14 January 2024.

 

Updated 12. March at 17:00 UTC

• The volume of magma beneath Svartsengi continues to increase, which could result in a new dike intrusion and possibly an eruption.
• An eruption could occur with very short notice, possibly less than 30 minutes.
• The most likely eruption site is between Stóra-Skógafell and Hagafell.

 

Model calculations show that magma accumulation at Svartsengi continues at a steady rate. In previous events a magma intrusion has formed when the volume of accumulated magma has reached 8 to 13 million cubic meters. The total volume accumulated now has already reach this threshold. Pressure buildup therefore continues to increase in the magma chamber and likelihood of a new dike intrusion and even an eruption in the next days is increased.

140 earthquakes have been detected in the vicinity of the Sundhnúkur crater row and Grindavík since Friday. The majority of these earthquakes have been minor or below magnitude 1.0 whilst the largest measured event was a M2.8 on Friday evening, at around 5km depth just SE of Þorbjörn. Seismic activity in the area has increased slightly in the past few days compared to last week, which can possibly be linked to calmer winds and optimal weather conditions for earthquake detections.

The IMO has updated the hazard assessment map. The hazard level remains unchanged from the last map. The new hazard assessment map took effect at 15:00 today, Tuesday, March 12th and is valid until March 19th, barring any changes to the situation.

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(Click on the image to see it larger)

Unusually rythmic pattern of unrest, upto this point.

As reported last week, the behavior of the dike propagation on March 2nd differed in some ways to the previous dike formations. Scientists will continue to gather data and infer if the event on March 2nd indicates possible changes to the unusually rythmic pattern of unrest with magma accumulation at Svartsengi and repeated dyke intusions and eruptions.

These events of unrest have previously been compared to the unrest in Krafla that started in 1975. During a period of 10 years, 20 magma intrusions occurred with 9 of them culminating in a volcanic eruption (See image below). In the Krafla unrest magma always intruded into the same dike, but at different scales of magnitude. However, the eruptions did not follow a similarly regular pattern as observed so far in the Sundhnúkar crater row and has in fact been unusually rythmic.

The image shows the interaction between magma intrutions and ground uplift in the center of the Krafla caldera. The graph below shows the elevation of measurement point within the Krafla caldera and the graph above shows the distance from the caldera to the dike formations.

 

Updated 7. March at 17:00 UTC

 

Likely sequence of events over the next several days:

 

• The volume of magma beneath Svartsengi continues to increase, which could result in a new dike intrusion and possibly an eruption.
• An eruption could occur with very short notice, possibly less than 30 minutes.
• The most likely eruption site is between Stóra-Skógafell and Hagafell.

 

Seismic activity associated with the volcanic unrest has been decreasing since Saturday, with very few earthquakes detected in the past few days. However, unfavorable weather conditions have disrupted seismic monitoring by dampening small events, so there have likely been additional minor earthquakes that could not be detected.

Weather conditions over the next 24 hours will likely hinder the Meteorological Office’s earthquake monitoring system. The forecast indicates that Reykjanes will experience strong winds from the southeast accompanied by rain and limited visibility, especially in mountainous regions. Precipitation will decrease in the early morning, with occasional showers coinciding with reduced visibility expected tomorrow and the following days.  Winds are expected to decrease over the weekend, coming from the southeast or northwest on Sunday.

Inflation continues at Svartsengi, and model calculations based on GNSS data from March 3rd to 6th indicate that approximately 1.2 million cubic meters of magma has been injected into the magma chamber during these days. Therefore, approximately 10 million cubic meters of magma has accumulated in the magma chamber overall since the last eruption. The current situation is therefore similar to what it was before the eruption on March 2nd.

Updated hazard assessment

The Meteorological Office has updated the hazard assessment map. The hazard level remains unchanged from the last map. One change has been made to the zoning; Zones 2 and 3 have been merged into one single zone. Given the development of the activity, there is no longer a reason to assess the risk in these areas separately. The new hazard assessment map took effect at 3 p.m. today, Thursday, March 7th. This hazard assessment is valid until March 12th, barring any changes to the situation.

 

(Click on the map to see it larger)

Updated 5. March at 14:20 UTC

 

Likely scenarios over the next few days:

• The volume of magma within the Svartsengi reservoir continues to increase, which could result in a new dike propagation and/or volcanic eruption in the coming days.  
• A volcanic eruption could start with a very short warning time, even less than 30 minutes.
• It is most likely that an eruption will occur in the area between Mt. Stóra-Skógfell and Mt. Hagafell. 

 

 

 

Seismicity over the dike has been low since the magma propagation ended on Saturday (2 March) evening. There is slightly more activity at Mt. Fagradalsfjall, where around 20 earthquakes have been detected in the last 24-hours.

Model calculations indicate a volume loss of about -1.3 million cubic metres from the Svartsengi magma reservoir on Saturday – which fed a 3-km long dike intrusion between Mt. Stóra-Skógfell and Mt. Hagafell. The volume loss from the Svartsengi reservoir was much lower than that which occurred during previous events, where a volume loss of about -10 million cubic metres was calculated.

Continuous land uplift is detected on GNSS observations since Saturday‘s magma propagation. Magma inflow beneath Svartsengi thus continues and model calculations suggest an inflow/accumulation rate of about half a million cubic metres per day. In total, about 9,5 million cubic metres of magma has been recharged to the reservoir beneath Svartsengi since the eruption on 8-9 February. 

Therefore, pressure in the magma reservoir continues to build up, and there is an increased likelihood of another dike propagation within the Sundhnúkur crater row and/or a volcanic eruption in the coming days.

 

 

The graph shows a comparison of volume increase within the Svartsengi reservoir prior to dike propagations and/or eruptions. The status of the volume change as of 4 March is indicated by the red line. This line also shows what affect the magma propagation on the 2 March had on the accumulation process within the magma reservoir beneath Svartsengi. The quantities displayed on this graph are derived from model calculations based on GNSS data alone. Joint InSAR-GNSS modelling of the diking event on Saturday indicates a volume loss of about -1.3 million cubic metres from the Svartsengi reservoir which fed the dike propagation within the Sundhnúkur crater row, without resulting in an eruption. Values derived from both the GNSS only and the joint InSAR-GNSS inversions are subject to uncertainty.

 

Weather conditions might affect IMO‘s monitoring systems.

 

The Icelandic Meteorological Office has updated the hazard assessment map, which is unchanged from the previous hazard assessment. The new hazard assessment is valid until Thursday, 7 March, unless developments in activity call for a re-evaluation.

 

 

The weather over the next few days is likely to affect the monitoring systems. The forecast for the week is southeasterly and easterly winds, around 10-15 m/s. Rain showers most days with increasing windspeeds and more calmer winds in between showers.

 

 

Updated 4. March at 16:00 UTC

 

Likely scenarios over the next few days:

• The volume of magma beneath Svartsengi continues to increase, which could result in a magma propagation and even a volcanic eruption.
• A volcanic eruption could start with a very short warning time, even less than 30 minutes.
• It is most likely that an eruption will occur in the area between mt. Stóra- Skógfell and mt. Hagafell.

Model calculations suggest that the volume of magma which propagated from Svartsengi to the Sundhnúkur crater row was around 1.3 million cubic metres.

It had previously been calculated that about 0.5 million cubic metres of magma accumulates beneath Svartsengi each day. Considering this, the total amount of magma beneath Svartsengi will be around 9 million cubic metres by the end of tomorrow, Tuesday 5 March.

In previous events, magma has propagated once the total volume of magma accumulated beneath Svartsengi reaches between 8-13 million cubic metres. Therefore, there is an increased likelihood of new magma propagation and volcanic eruption once these conditions are met.

However, it should be noted also, that after repeated eruptions in mt. Fagradalsfjall, there were examples of magma reaching slowly to the surface without much seismic activity. This sort of development should also be expected on the Sundhnúkur crater row.

 

Updated 3. March at 12:15 UTC

 

Likely scenario over the next few days

 

• Magma volume beneath Svartsengi continues to increase, which could lead to another magma propagation and even a volcanic eruption.
• A volcanic eruption could start with a very short warning time, event less than 30 minutes.
• A volcanic eruption is most likely to occur in the area between mt. Stóra-Skógfell and mt. Hagafell.

 

The Icelandic Meteorological Office has updated the hazard assessment map due to the decrease in seismic activity in the Reykjanes peninsula.

Considering the developments in activity since yesterday, the hazard level has been lowered in two zones – Zones 2 and 3. The hazard level remains unchanged in other areas, thus the hazard assessment is now the same as it was prior to yesterday‘s event.

The hazard assessment map is valid from 13:00 UTC today, 3 March, until 15:00 Tuesday 5 March unless development in activity call for a re-evaluation.

 

(Click on the map to see it larger)

Updated 3. March at 11:50 UTC

 

Seismic activity at mt. Sýlingarfell was due to a magma intrusion. The seismic activity started around 16:00 UTC yesterday (2 March) and subsided steadily after 18:00 and after 20:00 it was mostly over.

Data indicate that yesterday‘s magma intrusion has stopped by mt. Hagafell. The likelihood of magma ascending in relation to this magma intrusion has decreased but the area continues to be closely monitored for this possibility.

Model calculations indicate that the volume of magma that propagated out of Svartsengi yesterday was negligible comparted to previous magma propagations which culminated with an eruption.

Therefore, it can be assumed that magma accumulation beneath Svartsengi is continuing as before and that the volume of magma which has already been accumulated suffices to trigger another magma propagation. It can be expected that another magma propagation can occur in the next few days and there continues to be an increased likelihood of an eruption, as before yesterday‘s event.

This depends on how quickly the pressure caused by magma accumulation under Svartsengi builds up to trigger another magma propagation. 

Considering these developments, The Icelandic Meteorological Office is working on a new hazard assessment map which will be updated in the coming hours.

Likely scenarios over the next few days:

 

• Magma volume beneath Svartsengi continues to increase, which could lead to another magma propagation and even a volcanic eruption.
• A volcanic eruption could start with a very short warning time, event less than 30 minutes.
• A volcanic eruption is most likely to occur in the area between mt. Stóra-Skógfell and mt. Hagafell.

The graph shows a comparison of volume of magma accumulated beneath Svartsengi before it propagates towards Sundhnúkur crater row. The status of the magma volume at 2. March after the magma propagation er indicated with red colour. The amount is derived through model calculations based on GPS data and subject to uncertainties. Changes can vary from day to day, from being small to more prominent changes. The purple line shows the magma volume accumulated prior to the large diking event beneath Grindavík formed on the 10^th of November 2023. 

Updated 2. March at 19:10 UTC

 

At this point, the seismicity that began just before 16:00 UTC today has ceased. It is thus considered likely that the magma intrusion has stopped temporarily or is significantly diminished. However, minor deformation continues to be measured in the area, so it is too early to assert that the magma intrusion has ended, and that there will not be an eruption at this time. When magma intrusions occur, deformation can be measured for several hours after the seismic activity stops.

The Icelandic Meteorological Office continues to monitor the area to observe whether the activity resumes in the next few hours, or if the magma intrusion has halted completely. It remains possible that magma could ascend to the surface, as has been observed in eruptions near Fagradalsfjall.

 

Updated 2. March at 17:30 UTC

• An intense swarm of microseismic activity is occurring east of Sýlingarfell on the Reykjanes Peninsula.
• The seismicity indicates that magma movements have begun, and that a fissure eruption is likely.
• The seismicity began at the southern end of the fissure that formed on 18 December 2023.

• As of 17:30 UTC, it is apparent that the seismic activity has moved southwards in the direction of Hagafell.

• Real-time, GPS-based measurements show much less signs of deformation than before previous eruptions since December 2023. This could signify that less magma is on the move than before the previous three eruptions on Sundhnúkur crater row.
• At present, the depth of the seismicity does not indicate that magma is propagating to the surface.
• As of 17:30 UTC, the likely scenario is that the magma intrusion will not necessarily lead to a volcanic eruption. However, while the situation remains uncertain, a imminent fissure eruption cannot be ruled out.

A new hazard assessment map from IMO was published today and is valid until tomorrow (3. March 2024) at 17:00 UTC

Updated 29. February at 12:30 UTC

• An eruption could start with very little warning time, even less than 30 minutes.  
• Eruption location is most likely in the area between Mt. Stóra-Skógfell and Mt. Hagafell.  
• The hazard assessment does not account for weather conditions or other factors that may affect the risk of being within the hazard zones.
• It is possible that a dike intrusion occurs without resulting in a volcanic eruption.

 

Model calculations suggest that as of today, about 8.5-9 million cubic metres of magma has accumulated beneath Svartsengi. The rate of the inflation has been fairly constant for the past days. In previous developments, the rate of inflation has decreased shortly before an eruption starts.

According to model calculations, approximately 0.5 million cubic metres of magma is accumulated in the Svartsengi reservoir every 24 hours.

Considering precursors of previous volcanic eruption in the Sundhnúkar crater row, likelihood of a volcanic eruption increases once the volume of magma reaches 8 – 13 million cubic metres. If magma accumulation continues at the same rate, the amount should reach the upper limit next week.

There remains an increased likelihood of a volcanic eruption in the coming days. The most likely scenario is that a volcanic fissure opens in the area between mt. Stóra-Skógfell and Mt. Hagafell which could occur with a very short warning time.

The graph shows a comparison of volume of magma accumulated beneath Svartsengi before it propagates towards Sundhnúkur crater row. The status of the magma volume at 28^th of February is indicated with red colour. The amount is derived through model calculations based on GPS data and subject to uncertainties. Changes can vary from day to day, from being small to more prominent changes. The purple line shows the magma volume accumulated prior to the large diking event beneath Grindavík formed on the 10^th of November 2023. 

A new hazard assessment map from IMO was published today and remains unchanged from the previous one. The hazard assessment map is valid until 5^th of March unless developments in activity call for a re-evaluation. Likely scenarios presented earlier this week also remain unchanged (see news from 26^th of February).

Please note that although IMO has at this point not increased hazard level on the unrest area, developments can occur very quickly and without warning. People entering the unrest area need to keep this in mind. The hazard assessment by IMO does not account for weather conditions or other factors which may affect the risk involved when being within a hazardous area.

 

Updated 27. February at 13:00 UTC

• Accumulated magma beneath Svartsengi reaching same amount as prior to previous eruptions.
• An eruption could start with very little warning time, even less than 30 minutes.
• Raised hazard levels in an updated hazard assessment due to impending eruption.
• Eruption location is most likely in the area between Mt. Stóra-Skógfell and Mt. Hagafell.
• The hazard assessment does not account for weather conditions or other factors that may affect the risk of being within the hazard zones.
• It is possible that a dike intrusion occurs without resulting in a volcanic eruption

 

Model calculations suggest that about 7.6 million m³ of magma has been recharged within the Svartsengi reservoir. Considering precursors of previous volcanic eruption in the Sundhnúkar crater row, likelihood of a volcanic eruption increases once the volume of magma reaches 8 – 13 million m³. If magma accumulation continues at the same rate, the amount should reach the lower limit tomorrow (27^th of February).

Seismic activity has increased slightly since past weekend and has been most prominent just east of Mt. Sýlingarfell. The location of the seismic activity is in an area which is considered to be the eastern tip of the magma reservoir which is centered beneath the Svartsengi-Þórbjörn area.  The current seismicity is similar to that observed days before previous volcanic eruptions in the area.

Therefore, IMO has updated the hazard assessment for the unrest area. Increased likelihood of a volcanic eruption and related hazards affects the assessment. Hazard levels have been raised in several zones. Even though the color of Zone 4 – Grindavík – remains unchanged, the hazards there have increased due to the possibility of lava flows. Same goes for Zone 1 – Svartsengi.

No significant deformation within Grindavík has been detected by GNSS or satellite data. It is however likely that new faults will be revealed when snow melts or precipitation causes soil, which might be covering faults, to be washed away.

 

 

Likely scenarios

If an eruption occurs, scientists estimate that magma will most likely propagate from the reservoir beneath the Svartsengi-Þórbjörn region towards Sundhnúkur crater row, resulting in lava fountaining and lava flows in the area between Stóra-Skógfell and Hagafell. The primary signal of ascending magma is a sudden increase in seismic activity with many localized, small magnitude earthquakes. Considering the previous volcanic eruptions in the area, an eruption could start with very little warning (less than 30 minutes), depending on where magma reaches the surface on the Sundhnúkur crater row. 

 

 

At a community meeting held today with residents of Grindavík, IMO presented results from lava flow models, showing scenarios considered to be likely and which were explained before last weekend.

The modelled results presented showed estimated lava flow from two separate eruptive fissures located on the Sundhnúkur crater row. The lava flow models do not forecast the behaviour of the next volcanic eruption. The models are only used to predict possible lava flow pathways from different locations of eruptive fissures.

Many factors affect a lava flow: location and length of the eruptive fissure, volume of erupted material, topography of the land surface and whether craters or lava lobes form.

These modelled scenarios predict lava flowing from an 800 m long eruptive fissure with a constant extrusion rate of 600 m3/s.  The fissures are shown on the maps as black lines.

These modelled results below are therefore only 2 examples for the Sundhnúkar crater row, but the behaviour of the lava flow in the next volcanic eruption can be very different depending on where exactly a fissure opens on the surface and how long it will be. A minor shift in location can significantly alter the lava flow pathway.

 

 

Eruption between Sýlingarfell and Stóra-Skógfell – As occurred on December 18, 2023 and February 8, 2024. 

• Precursor: Sudden, localized, and intense seismic activity with small magnitude earthquakes. Deformation over the magma dike (if a dike is intruded) and the Svartsengi magma reservoir 
• Very short warning time (less than 30 minutes) because a new dike propagation may not be required for magma to reach the surface. 
• Lava reaches Grindavík road within 2 to 4 hours, but possibly less, if the velocity of the advancing lava front is higher than that observed during previous eruptions

The modelled results presented showed estimated lava flow from a fissure just south of Stóra-Skógfell. The lava flow models do not forecast the behaviour of the next volcanic eruption. The models are only used to predict possible lava flow pathways from different locations of eruptive fissures. The velocity of the advancing lava front can also be higher than that shown in the model.

 

Eruption by Hagafell – As occurred on January 14, 2024.

 

• Precursor: Seismic activity with small magnitude earthquakes on the Sundhnúkur crater row, starting near Sýlingarfell and migrating south. Deformation over the magma dike and the Svartsengi magma reservoir
• Likely warning time is approximately 1-3 hours from the detection of the first earthquakes until the start of an eruption.
• Lava reaches the lava barriers around Grindavík within 1 hour.
• Magma intrusion, which reaches south of Hagafell, will likely cause significant fault movements in Grindavík

The modelled results presented showed estimated lava flow from a fissure west of Hagafell. The lava flow models do not forecast the behaviour of the next volcanic eruption. The models are only used to predict possible lava flow pathways from different locations of eruptive fissures. The velocity of the advancing lava front can also be higher than that shown in the model.

 

Eruption inside of the lava barriers around Grindavík

 

• Seismic activity with small magnitude earthquakes on the Sundhnúkur crater row, starting near Sýlingarfell and migrating south. Deformation over the magma dike and the Svartsengi magma reservoir
• Probable warning time is between approximately 1-5 hours from the detection of the first earthquakes until the start of an eruption.
• It is possible that an eruptive fissure/s will open within Grindavík or the region just north of here (inside the barriers). Similar activity occurred on the 14^th of January when a volcanic fissure opened just inside the outer perimeter of the town approximately 4 hours after an onset of the eruption near Hagafell.
• Magma intrusion, which reaches south of Grindavík, will cause significant fault movements in Grindavík.

The Icelandic Meteorological Office and the University of Iceland have compiled material that describes the Volcano-tectonic reactivation of the Reykjanes Peninsula since 2019. See here .

 

Updated 23. February at 15:00 UTC

 

Model calculations indicate that approximately 5 million cubic meters of magma had recharged to the Svartsengi reservoir as of the 22 February. Considering the trend observed prior to previous volcanic eruptions in the Sundhnúkur crater row, the likelihood of an eruption is very high once the volume reaches between 8-13 million cubic meters (derived from joint InSAR-GNSS models). Based on the results of the model calculations, this could occur early next week if magma accumulation continues at the current rate.

It should be noted that there is a degree of uncertainty in this interpretation, and it cannot be assumed that the behaviour will be identical to the past eruptions here. Also, as the magma plumbing system evolves, we cannot rule out the possibility that the volume of magma required to trigger a new diking event and/or eruption may become reduced.

Additionally, there is a possibility a new dike intrusion occurs within this region without resulting in a volcanic eruption.

 

 

 

 

 

Figure: The graph displays a comparison of the volume of magma accumulated beneath Svartsengi before the magma flowed towards the Sundhnúkur crater row during the recent dike intrusions and eruptions that occurred between December 2023-February 2024. The volume is calculated by a model based on GNSS data and is subject to uncertainty. Significant variations can also be observed between consecutive days. The current magma accumulation status as of February 22 is marked by the purple line. The red line shows the amount of magma accumulated before the major diking event beneath Grindavík on November 10th.

 

 

 

If an eruption occurs, scientists estimate that magma will most likely propagate from the reservoir beneath Svartsengi towards Sundhnúkur crater row, resulting in lava fountaining and lava flows in the area between Stóra-Skógfell and Hagafell. The primary signal of ascending magma is a sudden increase in seismic activity with many localized, small magnitude earthquakes. Considering the previous volcanic eruptions in the area, an eruption could start with very little warning (less than 30 minutes), depending on where magma reaches the surface on the Sundhnúkur crater row.

 

Likely scenarios

Eruption between Sýlingarfell and Stóra-Skógfell – As occurred on December 18, 2023 and February 8, 2024.

• Precursor: Sudden, localized, and intense seismic activity with small magnitude earthquakes. Deformation over the magma dike (if a dike is intruded) and the Svartsengi magma reservoir 
• Very short warning time (less than 30 minutes) because a new dike propagation may not be required for magma to reach the surface. 
• Lava reaches Grindavík road in less than 4 hours.

Eruption by Hagafell – As occurred on January 14, 2024.

• Precursor: Seismic activity with small magnitude earthquakes on the Sundhnúkur crater row, starting near Sýlingarfell and migrating south. Deformation over the magma dike and the Svartsengi magma reservoir
• Likely warning time is approximately 1-3 hours from the detection of the first earthquakes until the start of an eruption.
• Lava reaches the lava barriers around Grindavík within 1 hour.
• Magma intrusion, which reaches south of Hagafell, will likely cause significant fault movements in Grindavík

Eruption inside of the lava barriers around Grindavík

• Seismic activity with small magnitude earthquakes on the Sundhnúkur crater row, starting near Sýlingarfell and migrating south. Deformation over the magma dike and the Svartsengi magma reservoir
• Probable warning time is between approximately 1-5 hours from the detection of the first earthquakes until the start of an eruption.
• It is possible that an eruptive fissure/s will open within Grindavík or the region just north of here (inside the barriers). Similar activity occurred on the 14^th of January when a volcanic fissure opened just inside the outer perimeter of the town approximately 4 hours after an onset of the eruption near Hagafell.
• Magma intrusion, which reaches south of Grindavík, will cause significant fault movements in        Grindavík.

 

Although there is clear indication of uplift in the Svartsengi-Þórbjörn area (related to magma recharge of this reservoir) this does not mean that it is the most likely location for an eruption to start. This is because the magma reservoir is currently failing on its northeastern edge feeding dike propagations which are initiated between Stóra-Skógfell- and Sundhnúkur crater row.  In a scenario where magma ascends towards the surface directly from the Svartsengi reservoir, it is estimated that the first signs of magma migration would be detected 4-7 hours before magma reaches the surface.

Please note that these scenarios are based on interpretations of the latest data and the observed development of the previous events at the Sundhnúkur crater row area. Uncertainty must be accounted for in this interpretation, as it is only based on few events.

 

 

Updated 23. February at 9:30 UTC

 

Seismic activity in the unrest area north of Grindavík remains minimal. About 20 small earthquakes have been detected on a 24-hour basis for the past days.

Magma accumulation beneath Svartsengi continues and the pace of the accumulation has been quite steady. This is a similar trend as has been observed prior to the previous volcanic eruptions.

The event which started at the end of October 2023 with an inflation at Svartsengi thus continues. Whilst magma accumulation persists, another volcanic eruption is expected in similar areas as before.

Should magma accumulation continue at current pace, the amount will reach a threshold believed necessary to trigger a dyke propagation and even an eruption, by next week. The amount of magma accumulated beneath Svartsengi before previous eruptions is estimated to have been 8-13 million m³. New model calculations are underway to obtain a better understanding of how much magma has now been accumulated.

At the moment, it is not considered necessary to raise the hazard level in the area and thus the hazard assessment issued by IMO remains unchanged.

The hazard assessment will be updated Monday 26^th of February and should the development continue at similar rate as now, hazard levels in zones will be raised as more magma will be accumulated and thus there is a higher likelihood of an eruption.

(Click on the map to see it larger)

 

Updated 20. February at 11:00 UTC

 

The Icelandic Meteorological Office has issued an updated hazard assessment map following the decision of the National Police Commissioner to repeal the order of a temporary evacuation from Grindavík, taking effect on the 19th of February, and due to the decision of the Police Commissioner in Suðurnes regarding changes in access restrictions for both individuals as well as business operations.

An updated hazard assessment map is valid from 20^th of February at 7AM, which is the same time as the decision of the Police Commissioner in Suðurnes goes into effect.

In the latest version of IMO’s hazard assessment map, Zone 7 has been added in consultation with Civil Protection. Nesvegur road is within Zone 7, which is currently more used to access Svartsengi and Grindavík. Hazards present in Zone 7 are fault movements and sinkholes. Colour code of other areas remain unchanged from previous hazard map.

Read here about the decision of the Police Commissioner in Suðurnes. (Icelandic).

As before, the map shows assessment of hazards currently at hand, as well as hazards which might occur with short notice. An assessment has only been made for hazards within the defined Zones, but hazards can also be present outside of them.

 

Updated 15. February at 16:00 UTC

 

Land uplift at Svartsengi area continues at similar trends and rates as has been detected following dyke propagations from there.

 Model calculations based on GPS data suggest that magma accumulation from the end of the eruption 9^th of February until yesterday, 14^th of February, is about 2 million m³. It was estimated that when the eruption began on the 8^th of February, about 10 million m³ of magma propagated from Svartsengi towards Sundhnúkur crater row. If magma accumulation continues at same rate, a total of 10 million m³ will be accumulated by the end of February or beginning of March, by which time likelihood of dyke propagation and volcanic eruption will increase significantly. These model calculations are based on GPS data but will be updated when new satellite data comes in.

Seismic activity in the western parts of mt. Fagradalsfjall continues with about 80 small earthquakes of magnitudes 1.5 or smaller detected since 12^th of February. The depth of the earthquakes under the western part of mt. Fagradalsfjall is at 6-8 km. The area remains closely monitored but at the moment deformation data do not show signs of magma accumulation.

An updated hazard map has been published. It is valid until 22^nd of February unless developments call for a re-evaluation. The main changes are that likelihood of eruptive vents opening has decreased in all Zones. Likelihood of sinkholes and fault movements are still considered high in Zone 4 (Grindavík). Please note that the hazard zones are active, and changes can occur with short notice. Furthermore, hazards can be present outside of the specified hazard zones, such as the faults that formed on the 10^th of November 2023 west of Grindavík (see faults on map).

(Click on the map to make it larger)

 

Updated 12. February at 16:00 UTC

 

IMO has updated the hazard assessment according to the development of the eruptive activity. Changes have been made to the hazard assessment for some hazards within zones. 

The overall hazard assessment for the area remains unchanged from the last map. There is still considered to be a sinkholes and fault movementsn area 4 (Grindavík).

(Click on the map to make it larger)

The hazard assessment map is valid until Thursday, 15 February, unless changes in activity calls for a re-evaluation.   

 

Updated 12. February at 14:30 UTC

 

Inflation has started again at Svartsengi after having subsided following the eruption which started 8. February. Inflation rate is about 0.5-1.0 cm/day which is in similar to the rates detected prior to last eruptions. Magma thus continues to accumulate in the magma reservoir beneath Svartsengi. It is therefore highly likely that the cycle continues in a few weeks with another dyke propagation and a volcanic eruption.

Time series from the GPS station Svartsengi (SENG) since 11^th of November 2023 in the north, east and vertical directions (top, middle and bottom images, respectively). The bottom time series show land uplift in millimetres and yesterday’s datapoint (11^th of February) is shown with a green dot. The red vertical lines are timings of the last three eruptions (18^th of December 2023, 14^th of January 2024 and 8^th of February 2024).

Since noon of 8. February, seismic activity in the area north of Grindavík has been minor, about 50 small earthquakes have been detected, all of which were around or less than M1.0. A small seismic swarm has been ongoing in the western parts of Mt. Fagradalsfjall with about 100 earthquakes detected, mostly M1 events or smaller. Minor swarms in the Fagradalsfjall area have occurred frequent for the past weeks, the depth of the earthquakes is at around 6-8 km.

 

Updated 9. February at 15:30 UTC

 

No eruptive activity was observed in a drone-flight over the eruptive site carried out at noon today (9February) by the Special Unit of the National Police Commissioner. This suggests that the eruption is ending. Volcanic tremor is no longer being detected on seismic sensors.

IMO has updated the hazard assessment according to the development of the eruptive activity. Changes have been made to the hazard assessment for some hazards within zones. Hazards due to opening of volcanic fissures has decreased, but hazards due to gas pollution are still considered to be likely by the lava flow front. Hazards due to lava flow is still in place, as lava lobes can burst out from the lava flow front. Hazards due to sinkholes and fault movements are still considered high in Zone 4 (Grindavík).

(Click on the map to see it larger)

The hazard assessment map is valid until 15:00 on Monday, 12 February, unless changes in activity calls for a re-evaluation.   

 

Updated 9. February at 13:00 UTC

 

Volcanic tremor has significantly decreased since yesterday (8th of February). The decrease was detected shortly after noon yesterday alongside decreased eruptive activity on the volcanic fissure and activity became more confined in separate craters. Temporary increases of the volcanic tremor were noted last evening, which coincided with increased volcanic activity in the craters. During the night, the activity decreased further and between 7 and 8 this morning, two eruptive craters were active. For the past hours no lava fountaining has been observed on web-cameras but activity within the craters might still be ongoing.

Satellite radar image taken at 14:56 yesterday shows surface subsidence of 10 cm in Svartsengi area, north-west of mt. Þorbjörn, when magma flowed from there towards Sundhnúkur crater row. Model calculations based on these data suggest that about 10 million m³ of magma has flowed from the magma reservoir beneath Svartsengi towards the eruption site at Sundhnúkur crater row. 

(Click on the Insar Satellite Image to make it larger)

Seismic activity at the eruptive site has been minor during the past 24 hours. About 40 earthquakes have been detected there, all around or smaller than M1.

Volume estimates of the erupted lava from the start of the eruption at 6:02 until 13:00 yesterday (8^th of February) is about 15 million m³, which corresponds to an average extrusion rate of 600 m³/s during the first seven hours (data provided by Icelandic Institute of Natural History and Landmælingar Íslands).

Although the eruption has significantly decreased it is still too early to declare if it has come to an end. IMO maintains a 24-hour watch and keeps a close eye on the area. An updated hazard assessment will be published later today.

 

Updated 8. February at 17:15 UTC

 

The vigor of the eruption continues to decrease. The eruptive activity is currently on two or three locations on the eruptive fissure. The explosive activity which began between 13 and 14 o‘clock is now mostly over, but minor convective clouds rise from some parts the fissure.

Synchronously with the decreasing vigor of the eruption, the deformation signals detected at the dyke area diminished, indicating that magma is no longer ascending under as much pressure as before. Soon after the onset of the eruption, seismic activity decreased significantly and has remained minor thus far. About 20 small earthquakes have been detected over the dyke since 08:00 this morning.

The map shows outlines of the lava flow as it was seen on a satellite image taken at 12:31 today (Thursday 8^th– of February). The satellite image shows that lava flowed furthest about 4.5 km to the west from the eruptive site. For comparison, the lava flow field which formed in the eruption on the 18th of December 2023 is also shown on the map. Today ‘s lava flows partly over the lava flow formed in December 2023.

(Click on the map to make it larger)

IMO has updated the hazard assessment map considering the process of the eruptive activity. Changes have been made to the hazard assessment for some hazards within zones. However, these changes do not influence the overall hazard assessment for the zones. The new lava flow field has also been added to the map. The hazard assessment map is valid until 19:00 tomorrow, Friday 9th of February 2024, unless development in activity calls for a re-evaluation.

 

(Click on the map to make it larger)

Updated 8. February at 14:25 UTC

 

The vigor of the eruption is decreasing. The activity is now mainly on 3 locations on the eruptive fissure which opened this morning. This is not unlike the process observed in the eruption 18th of December 2023, when the activity was confined to a few craters few hours after the onset of the eruption.

A conspicuous, dark plume rises from one part of the eruptive fissure. This is likely due to magma interaction with groundwater which results in a slight explosive activity where white plume of steam mixes with dark volcanic plume.

It seems that tephra does not travel far from the eruptive fissure at the moment. The volcanic plume is dispersed towards south-west.

Photo taken towards north-west. (Photo: Special Unit of the National Police Commissioner).

 

Updated 8. February at 12:20 UTC

 

Geodetic data suggest that deformation has decreased significantly in the dyke area. Therefore, probability of new eruptive fissure openings has decreased. 

IMO has received notifications of tephra fall in Grindavík. 

Tephra is frothy and vesicular material which forms when splashes of lava cool quickly in the air in the lava fountaining activity. This process took place when an eruptive fissure opened this morning (8th of February 2024). Due to the tephras‘ vesicularity and lightness it can be transported far within the volcanic plume with wind. It falls in Grindavík now, 3-5 km from the source of formation due to the height of the lava fountains, north-easterly wind-direction, thermal upwelling from the lava and low air temperature.

Tephra is a synonym for all airborne, solid, eruptive materials, regardless of size an type. Tephra formation is well known in Iceland, such as in the explosive eruptions in Grímsvötn 2011 and 2004, and Eyjafjallajökull 2010. In explosive eruptions, the lava is more fragmented in the air an produces finer-grained tephra but tephra can also be produced in effusive eruptions such as is now ongoing on the Reykjanes peninsula. In effusive eruptions, the majority of tephra is deposited close to the vent and thus is not well detectable outside of the lava flow field. In May 2021, when lava fountaining was most active in the eruption in Fagradalsfjall, large pieces of tephra (up to 10 cm in diameter) fell at about 1 km distance from the eruptive source.

Tephra is sharp as glass and thus should be carefully handled. Windscreen wipers should not be used to remove tephra from vehicles as it will scratch the glass. Tephra should rather be blown or washed off with water of windows and similar surfaces.

Gas dispersion

 

Weather forecast for gasdispersion from the volcanic site is north-easterly winds, 4-8 m/s today (Thursday), thus gas is dispersed towards south-west. Decreasing wind speed tonight which can cause gas concentrations to build up at the volcanic site. Easterly and south-easterly winds, 5-10 m/s after noon tomorrow (Friday), causing gas to be dispersed to the west and north-west, towards Keflavík.

 

Updated 8. February at 11:40 UTC

The Icelandic Met Office has updated the hazard map for the area. The hazard level has increased in all areas due to the eruption.

Updated 8 February at 7:50 UTC

 

At 5:30 this morning an intense seismic activity started north-east of mt. Sýlingarfell. Around 30 minutes later, a volcanic eruption started at the site.

The eruptive fissure lengthened both towards north and south during the first minutes.

The first images from the Icelandic Coast Guard’s surveillance flight  suggest that the eruption takes place at a similar location as the eruption on the 18th of December 2023. The eruptive fissure is approximately 3 km long, from mt. Sundhnúkur in the south and stretches towards the eastern part of mt. Stóra-Skógfell. Lava flows mostly towards west at the moment and the flow seems to be slightly less than at the start of the 18th of December eruption.

 

The lava fountains reach about 50-80 m height and the volcanic plume rises about 3 km above the eruptive fissure. 

 

Image from the Icelandic Coast Guard’s surveillance flight. Mt. Stóra-Skógfell in the foreground and the lights at the Svartsengi power station to the right. (Photo: Björn Oddsson).

 

Updated 5 February 16:00 UTC

 

Ongoing magma accumulation beneath the Svartsengi-Þorbjörn area continues, even though the rate of inflation has decreased slightly in recent days. Similar processes were observed before the previous dyke intrusions and eruptions north of Grindavík in January 2024 and December 2023. According to updated geodetic models based on satellite and GNSS data covering the interval from 16 January to 5 February, the volume of magma recharge to the Svartsengi reservoir is now estimated at about 9 million m³. From geodetic modelling of the January 2024 intrusion and eruption, it is estimated that approximately 9 to 13 million cubic meters of magma flowed from the Svartsengi magma reservoir, feeding the eruption that began near Hagafell on 14 January. Therefore, the estimated volume of magma recharge has now reached the lower limit of the amount believed to have been tapped in January. Consequently, there is an increased likelihood of a new magmatic dyke intrusion and ensuing volcanic eruption in the coming days to weeks.

Since last Friday, nearly 200 earthquakes have been measured in the area north of Grindavík, most of them around or below magnitude 1 at depth of 3-4 km. The largest earthquake occurred on the morning of Sunday, 4 February, near Sundhnúkur, and was a M2.2 at a depth of approximately 6 km.

The IMO continues to closely monitor the area, and the current hazard assessment map remains valid until 3:00 PM on 8 February, if there are no changes in activity.

Latest satellite radar comparison, showing ground surface changes between 23 January and 4 February 2024. Red shading show the area of maximum inflation and grey shading shows area where measurements were not possible due to variations in snow cover between images.

 

Updated 1 February 17:00 UTC

 

Models based on GPS data, reviewed this morning (1 February) by scientists from the Icelandic Meteorological Office and the University of Iceland, indicate that approximately 6.5 million cubic meters of magma has accumulated beneath the Svartsengi region. According to this assessment, magma will soon reach the same volume as drained during the January 2024 eruption. Therefore, the timescale for the next eruption could be within two weeks or possibly days. This means that the likelihood of a magma intrusion, and a volcanic eruption, have increased.

There is no absolute certainty that the warning time ahead of the next intrusion or eruption will be the same as 14 January, which was about a five-hours’ notice from the beginning of the earthquake swarm until the eruption began just south of Hagafell. The warning period for the eruption between Stóra-Skógfell and Sundhnúkur on 18 December last year was about 90 minutes, and that eruption occurred approximately at the mid-point of the (now solidified) magma intrusion beneath the Sundhnúksgígar crater row. With repeated lateral magma intrusions, it is likely that the pathway for magma propagation to the surface will be easier, resulting in less seismicity. However, rapid movements of magma are always accompanied by increased micro-seismicity. We assess that the minimum warning time would be one-hour ahead of a volcanic eruption, and that the most likely pathway would be along the fissures from the magma intrusion on 10 November last year.

Seismic activity has been similar over the past week. Nearly 200 earthquakes have been measured in the area between Stóra-Skógfell and south of Hagafell in the past seven days. Most of these earthquakes were minor, under 1.0 in magnitude, at a depth of 2 to 5 km. The largest earthquake registered magnitude 1.8, and it was located about a kilometre south of Hagafell.

The Icelandic Meteorological Office has issued an updated hazard assessment map. The main changes are that zone 3 (Sýlingarfell – Hagafell) has been upgraded to red (high hazard), and zones 2 and 6 have been upgraded to amber (considerable hazard). Grindavík (zone 4) remains unchanged at a considerable level of hazard.

 

The overall assessment for each zone is based on a combined evaluation of seven types of hazards that could occur within individual zones. The list on the map shows hazards within the zones that are rated as “considerable”, “high,” or “very high”. Hazards rated as “high” or “very high” are highlighted in bold.

 

 

It should be noted that although the overall hazard assessment for Grindavík remains the same as last week, the lava-flow hazard is now assessed as high. The hazard of sinkholes opening over fissures within Grindavík is still rated as very high.

Updated 25 January 17:30 UTC

 

Inflation continues at Svartsengi. Over the past few days, the land has been rising at a rate of approximately 8 mm per day, slightly exceeding the recorded rate of uplift before the eruption on January 14th.

At this point, it is challenging to determine exactly how much magma has accumulated beneath Svartsengi since the eruption ended on January 16th. Most likely, the timeframe required to reach the same volume of magma as before the last eruption will be on the order of weeks, not days. Computational models are being refined to obtain a clearer assessment of the status of magma accumulation.

Low levels of seismic activity persist and are mostly concentrated around Hagafell. The current seismic activity aligns with that observed in the area following the previous eruption.

The Icelandic Meteorological Office has issued an updated hazard assessment map. The main changes include reducing the overall hazard level for Grindavík to orange (significant hazard).

It should be noted that, although the overall hazard level for Grindavík has been reduced by one level, the hazard associated with fissures remains very high. The current hazard is now referred to as “subsidence into a fissure,” describing the danger that may be present where fissures are hidden beneath unstable surfaces that could collapse and develop sinkholes.

The hazard assessment related to fissure development within Grindavík has decreased. Evaluations are underway to determine if there is a danger of existing fissures expanding or new fissures forming. GPS data have exhibited very little movement within Grindavík the past few days, reducing the assessed hazard compared to before. The hazard due to sinkholes overlying fissures is now considered significant.

(Click on the picture to see it larger). Increased hazard in the area due to the eruption near Hagafell on January 16th and land uplift near Svartsengi. Conditions within and outside the hazard areas can change with little warning. Hazard assessment is focused solely within these areas, but the danger may extend beyond them. The overall hazard assessment for each area is based on a combined evaluation of 7 types of hazards present or possible within the regions. The color of each area reflects the overall hazard within those boundaries.

 

Updated 19 January 16:30 UTC

 

Clear signals of a continued land uplift are still being detected beneath Svartsengi. It is yet too early to assert whether the rate of the land uplift has increased since prior to the eruption on January 14. First measurements suggest that is the case, but as has previously been written measurements can fluctuate from one day to the next and a longer timeline of measurement is needed to be able to interpret the long-term development of the land uplift.

Seismic activity continues to decrease in the area of the magma dyke and deformation signals seen on GPS devices suggest significant slow down of ground movement compared to previous days. This information suggest that magma is no longer flowing into the dyke and the eruption has ended.

GPS measurements also show small deformation within Grindavík. There is still high danger of ground collapse into fissures within the town and thus important to map new fissures and changes to known ones estimated.

The Icelandic Meteorological Office has updated the hazard assessment due to the volcanic and seismic activity. Hazard level has been decreased in all zones.

An overall hazard assessment for zone 1, Svartsengi, is now down to yellow (moderate hazard).

An overall hazard assessment for zone 4, Grindavík, is now down to red (high hazard). Note that the colour of zones represents the overall hazard within those zones. A hazard which is rated greater within a zone is written in bold letters in the list of hazards on the map.

The the hazard assessmept map takes effect at 15:00 today, Friday January 19 and is valid until Thursday, January 25, at 15:00, unless there are significant developments.

 

Updated 18 January 15:30 UTC

 

As reported in the news yesterday, clear signs of land rise persist beneath Svartsengi, but it is still too early to determine the rate of the uplift due to the recent volcanic activity in the area. GNSS measurements are being evaluated to provide a comprehensive assessment of the situation. However, it appears that the deformation remains similar to that observed after the volcanic eruption on December 18.

Around 200 earthquakes have been recorded near the magma conduit since yesterday, with the largest measuring 1.4 in magnitude. Since midnight, approximately 70 small earthquakes have occurred, which is fewer than measured the day before. The weather has impacted the number of earthquakes detected in recent days, but the number of earthquakes seems to have decreased overall.

A significant risk remains in Grindavík due to fissures and the potential for ground collapse into them.

Updated 17 January 18:00 UTC

 

 

Magma accumulation continues under Svartsengi. It is too early to assert the rate of the land uplift shortly after the volcanic eruption. Experts will continue to assess data from GNSS stations in the area to get an overall assessment of the situation. One of the meters, which was located north of Grindavík, went under lava, but over 20 GNSS stations are in the area and are being used.

Seismic activity has been mild over the magma conduit in the last 24 hours. According to computational models, magma lies shallow at the southern end of the conduit, where the land appears to be heavily fractured, making it easier for the magma to reach the surface. Therefore, there is a continued likelihood that new eruptive fissures may open without warning.

There is still danger within Grindavík related to fissures and the potential for ground collapse into them. Significant deformation has occurred in connection with the graben in the eastern part of the town. These movements were mostly along the fissures that formed on November 10 and had already been mapped.

Gas pollution was measured yesterday during work on wells connected to the utility system within Grindavík. The Icelandic Meteorological Office does not monitor localized gas pollution within Grindavík. It needs to be further examined whether or not the gas pollution is related to the magma lying very shallow in the area. It should be noted that dangerous gas pollution is among the issues mentioned in the current hazard assessment for Grindavík.

The IMO has issued an updated hazard assessment map. There are no changes in the overall hazard assessment for the areas compared to what was previously. The map takes effect at 15:00 today and is valid until Friday, January 19, at 15:00, unless there are significant developments.

 

Updated 16 January 18:00 UTC

 

Magma continues to accumulate beneath Svartsengi at a rate similar to that observed before the last two eruptions. This was the consensus reached during a consultation meeting of scientists this morning. During the eruption this past Sunday, similar to the December 18 eruption, magma flowed eastward from the accumulation site beneath Svartsengi, creating a magma conduit extending from Stóra-Skógfell southward beneath Grindavík. Computational models support this observation and indicate that the origin of the magma was slightly further west compared to the previous eruption, leading to variations in recent GPS measurements compared to those recorded on December 18.

As a magma conduit forms close to the surface, the Earth’s crust is strained, causing the land above the central part of the conduit to subside and form a graben. Additionally, the ground is elevated on either side of it. Computational models reviewed at the consultation meeting show that the GNSS station in Svartsengi is located at the edge of the conduit, where the land rises as the conduit forms. Now, two days after the conduit’s formation, the Svartsengi GNSS station is expected to show subsidence if magma accumulation has ceased. However, this is not observed, indicating that magma accumulation continues as before.

The magma conduit generated in the eruption that began on Sunday lies slightly further east than the conduit that extended under Grindavík on November 10. Data collected and processed by the Icelandic Institute of Natural History and the National Land Survey of Iceland reveal that a new graben has formed east of the one that appeared on November 10. The newly formed graben measures approximately 800-1000 meters in width, as shown on the map below. The greatest subsidence within it is approximately 30 cm, but it is worth noting that the region is still experiencing subsidence, and the valley is progressively widening. In comparison, the graben that developed in Grindavík on November 10 had a width of about 2 km, with the most significant subsidence measuring around 1.3 meters.

Inside this recently formed graben, previously mapped fissures that were visible on the surface have expanded, and additional fissures have emerged. Consequently, the risk associated with these fissures and the possibility of ground collapse into them have increased in the eastern section of Grindavík compared to before.

 

Map showing the location and width of the graben formed on November 10th (“Mörk sigdals 10-11. nóvember”) and the newest graben that recently formed to the east (“Mörk sigdals 14-15. janúar”).

Updated 16 January at 11:45 UTC

 

There is currently no visible activity within the eruptive fissures, with the most recent lava observed emanating from the northern fissure shortly after 1 am last night. Seismic activity continues to decrease, signifying that the area is stabilizing. Approximately 200 small earthquakes were recorded near the magma conduit since midnight, indicating that magma is still migrating. Most seismic activity is located near Hagafell, close to the first eruptive fissure that opened on Sunday morning. At this point, it is premature to declare that the eruption is over.

GPS sensors continue to detect ground deformation in and around Grindavík, illustrating that the magma conduit beneath Grindavík is still causing expansion in the area. Thermal images from a drone last night show that fissures previously mapped southwest of Grindavík have significantly enlarged. Considerable hazards persist in the area.

 

Updated 15 January at 16:40 UTC

 

Based on webcam footage, it is evident that the lava flow has decreased from the eruptive fissures that opened yesterday. Flow from the southern eruptive fissure, which emerged around noon yesterday near the town‘s border, seems to have ceased. The majority of the remaining lava flow is now directed southwest along the protective barriers, and its trajectory seems to have stabilized.

It is difficult to estimate how long this eruption will last. Seismic activity has decreased, and GPS measurements indicate that the rate of deformation in the area has reduced. However, deformation is still detected near the southernmost part of the magma conduit beneath Grindavík.

Measurements indicate that there has been a displacement of up to 1.4 meters in the past 24 hours, distributed across numerous fissures within the town‘s boundaries. Fresh fissures have developed, and existing ones have expanded. It is possible that additional fissures may emerge on the surface in the next few days.

As previously stated, the eruption sites are extremely hazardous, and the possibility of new fissures emerging without warning cannot be dismissed. This was demonstrated by the eruptive fissure that appeared near the border of Grindavík yesterday, which provided no recognizable warning signs on the monitoring equipment.

Today, there is a mild wind from the northeast at the eruption sites, but it will pick up speed later in the day. Therefore, gas pollution is drifting southwest towards the ocean. Tomorrow, the area will experience winds from the north reaching 10-18 m/s, causing the gas to drift south. Refer to the weather service’s forecast for gas dispersion details.

The Icelandic Meteorological Office continues to monitor the area and is in direct contact with civil protection and response teams in the region about the progression of the event.

Scientists met this morning for a consultation meeting organized by the Icelandic Meteorological Office. They reviewed the most recent data related to the eruption.Top of Form

In the upcoming days, there will be ongoing measurements and the collection of additional data, followed by analysis. These data are being utilized, among other things, to construct models that enhance comprehension of the pre-eruptive indicators that led up to this event and to evaluate the most likely progression of the eruption. Comparisons are also being made between the December 18 eruption and the eruption that began yesterday to enhance understanding of changes in the area and to evaluate the most likely scenarios going forward.

The Icelandic Meteorological Office has issued an updated hazard assessment map based on the latest data. It remains unchanged from the last update. The map is valid until 19:00 on Wednesday, January 17, unless new developments arise.

 

Kort, der viser lavaens udbredelse baseret på målinger udført af det islandske naturhistoriske institut og Islands Universitets institut for geovidenskab. Der blev gennemført undersøgelser to gange i går. Den mørkelilla form viser udstrækningen af ​​lavaen kl. 13.50 den 14. januar, mens den lyse lilla form viser udstrækningen kl. 16.15, næsten 2,5 timer senere. De eruptive sprækker er markeret med røde linjer, mens barriererne konstrueret for at forhindre lava i at nå Grindavík er repræsenteret med orange stiplede linjer

Kort, der viser tykkelsen af ​​lavastrømmen baseret på målinger kl. 13:50 i går.

Opdateret 14. januar kl. 15:30 UTC

 

 

Udbruddet nær Hagafell-Grindavík har bevaret samme styrke den seneste time eller deromkring.

Seismiske målinger viser, at ved begyndelsen af ​​urolighederne i morges (~2:30 om morgenen), flyttede den magmafyldte digeindtrængning sig først fra den SE-kant af Stóra-Skógfell og fortsatte derefter mod sydvest til den sydlige ende af Grindavík. Klokken 05.30 havde seismiciteten nået den nordlige ende af Grindavík, og både seismicitet og deformationsmålinger indikerer, at diget siden har forplantet sig under Grindavík by. En ny eruptiv sprække åbnede kl. 12:10 i eftermiddags, lige nord for byen. Lavastrømme ekstruderet fra denne sprække er nu kommet ind i byen.

På grund af digets udbredelse blev eksisterende forkastninger og sprækker reaktiveret, og der er sandsynligvis dannet nye sprækker i Grindavík.

 

Gas distribution

Det islandske meteorologiske kontors vejrudsigt for gasfordeling fra udbruddet ved Hagafell indikerer, at retningen er nord og nordøst, med en hastighed på 3-8 m/s, og vejret er tørt og lyst i dag. Det bliver til tider overskyet med mindre snefald sent i aften og i morgen tidlig. Det vil klare op om eftermiddagen i morgen. Forureningen fra udbruddet breder sig mod syd og sydvest.

 

Nyt farekort udgivet

Det islandske meteorologiske kontor har opdateret farevurderingskortet i lyset af fortolkningen af ​​de seneste data.

Risikoen er steget på alle områder. Farevurderingskortet er gyldigt indtil kl. 19.00, mandag den 15. januar, medmindre andet er angivet.

Opdateret 14. januar kl. 8:20

 

Et udbrud startede klokken 7:57 UTC

Sprækkeåbningen er sydøst for Hagafell-bjerget.

Den sydligste del af sprækken er omkring 900 m fra byen Grindavík.

Åbningen er syd for lavastrømsafbøjningsbarrierer, der bygges nord for Grindavík. Lava strømmer nu mod byen.

Et billede taget ombord på kystvagtens fly. Sprækkeåbning kan ses med lysene i Grindavík i det fjerne. Et kort, der viser sprækkeåbningen markeret med en rød linje.

 

Opdateret 14. januar kl. 06:15 UTC

Omkring 03:00 UTC i dag begyndte en intens serie af jordskælv ved Sundhnúksgígar-kraterrækken. 

På tidspunktet for offentliggørelsen er der målt over 200 jordskælv i området, og seismiciteten har bevæget sig mod byen Grindavík. 

So far, the largest recorded earthquake is 3.5 in magnitude, and it was measured at 04:07 UTC at Hagafell. 

Both real-time GPS measurements and borehole pressure readings (from HS Orka) show major changes since the onset of today’s earthquake activity. These observations, in addition to the ongoing seismicity, confirm that magma is moving within the region. 

Our assessment is that the possibility of an eruption is high, and that it could occur imminently.

A map showing the latest earthquake activity.

Updated 12 January at 17:45 UTC

 

The Icelandic Meteorological Office has updated the hazard assessment map for the Grindavík – Svartsengi region due to the ongoing unrest on the Reykjanes Peninsula. As before, the map shows an assessment of existing hazards that could occur with little warning within the specified regions. Note that the assessment applies only for hazards within the defined areas, although hazards are possible beyond the confines of the assessed regions.

In terms of colour-coding, the overall assessment for the six zones remains unchanged from the previous map. However, there is a change in the hazard assessment associated with fissures within Grindavík (zone 4). The hazards associated with sudden opening of mapped and unknown fissures within Grindavík is now deemed higher. It should be noted that the hazards associated with fissures is limited to known areas within the municipal boundaries.

Unless otherwise stated, the map is valid until Tuesday, 16 January 2024.

 

Updated 9 January at 13:00 UTC

 

Seismic activity continues to exhibit a pattern similar to that of recent days. The earthquake activity remains relatively low, primarily centered between Hagafell and Stóra Skógfell, where the center of the intrusion is situated. Additionally, there is ongoing seismic activity in Fagradalsfjall, persisting since December 18th.

Land uplift is still being measured in the Svartsengi area, exhibiting a relatively stable trend since the eruption on December 18th. The accompanying image, marked with red dots representing data from the GPS station SENG in Svartsengi, illustrates this trajectory The recent rate of uplift is approximately 5 mm per day, resulting in a current elevation that is about 5 cm higher than before the dike intrusion on November 10th and December 18th last year.

Calculations from models relying on deformation measurements (GPS and satellite images) indicate that the amount of magma accumulated in the reservoir beneath Svartsengi has reached a level comparable to the volume that led to the formation of the magma conduit and the subsequent eruption on December 18th last year. This suggests that there is an increased risk of an eruption in the coming days.

The Icelandic Meteorological Office issued an updated hazard map on January 5th, and it will be reassessed on January 12th.

 

Relative målinger fra GPS-stationen SENG i Svartsengi fra begyndelsen af ​​oktober 2023 til i dag, viser nord-, øst- og lodrette komponenter (top, midt, bund). Den nederste kurve viser landhævningen i millimeter, med dagens måling angivet med en grøn prik.

Opdateret 5. januar kl. 17:40 UTC

 

Et nyt farekort er udstedt af IMO. Kortet afspejler en farebaseret vurdering af Grindavík – Svartsengi-regionen, foretaget den 5. januar 2024. Farevurderingen er baseret på de seneste overvågningsdata, herunder seismisk aktivitet og jorddeformation, samt geodætiske modelleringsresultater. Vurderingen tager også højde for sandsynligheden for vulkanske farer i hver af de seks zoner, som vist på kortet.

I dagens vurdering påvirker hovedændringen Svartsengi-regionen (zone 1), som nu anses for at være på et moderat fareniveau, hvilket afspejler et fald i forhold til den tidligere version af farekortet. Begrundelsen for denne ændring er, at farevurderingen på grund af dannelsen af ​​større overfladebrud er faldet, da der ikke er dannet nye større brud på det seneste. Derudover gør de seneste geofysiske observationer sammen med vores videnskabelige konsensus Sundhnúksgígar til det bedste sted for et udbrud.

I mellemtiden fortsætter IMO med at overvåge området, og eventuelle ændringer vil blive kommunikeret direkte til civilbeskyttelsen via de sædvanlige kommunikationskanaler.

 

Opdateret 5. januar kl. 14:30 UTC

 

Landhævningshastigheden nær Svartsengi fortsætter med at falde. Eksperter samlet på Meteorologisk Kontor her til morgen bekræftede dette gennem en analyse af GPS-data. Som tidligere rapporteret, signalerer dette en stigning i magmatrykket, hvilket øger sandsynligheden for et nyt digeindtrængen og potentielt udbrud. Det kan dog ikke udelukkes, at dette alternativt kan tyde på et fald i magmatilstrømningen.

Cirka 490 jordskælv har fundet sted nær magmakanalen siden tirsdag den 2. januar. Blandt disse havde 14 en styrke på over 1,0, hvoraf det største målte 1,8 nord for Hagafell. Onsdag den 3. januar indtraf et jordskælv med en styrke på 4,3 nær Trölladyngja, kort efterfulgt af et jordskælv med en styrke på 3,5 og adskillige efterskælv; omkring 900 jordskælv er blevet målt i området.

Den seismiske aktivitet nær Trölladyngja den 3. januar fandt sted langs en anerkendt brudlinje, hvor større jordskælv tidligere er sket flere gange. Der er intet, der tyder på, at disse jordskælv er direkte forbundet med magmabevægelser. Ikke desto mindre er de bemærkelsesværdige ændringer i landskabet i forbindelse med vulkansk aktivitet i Fagradalsfjall, landhævningen nær Svartsengi, magmakanalen nær Sundhnúk den 10. november og udbruddet den 18. december blevet målt på tværs af det vestlige Reykjanes og påvirker seismisk aktivitet i hele regionen .

According to their evaluation, scientists conclude that in the event magma reaches the surface, the most probable site for a subsequent eruption would again be Sundhnúksgígaröðinni, situated between Stóra-Skógfell and Hagafell. However, it is important to remember that dike intrusions do not always culminate in an eruption, as evidenced by the activity at Fagradalsfjall and also during the Krafla fires. 

 

Updated 3 January at 12:30 UTC

At 10:50 AM, an earthquake of magnitude 4.5 occurred near Trölladyngja, followed shortly by another earthquake measuring 3.9 at 10:54 AM and a series of aftershocks. The earthquakes occurred at a depth of approximately 5 km and were likely triggered in response to stress released from earth movement elsewhere on the Reykjanes Peninsula. These earthquakes were widely felt in the southwest region of Iceland.

The location of the earthquakes is about 20 km NNE of Svartsengi, where land rise due to magma accumulation is ongoing. 

The accompanying image shows the location of the earthquake that occurred at 10:50 AM and its impact area.

Updated 2 January at 14:00 UTC

 

The rate of ground displacement at Svartsengi is decreasing. Experts gathered at the Meteorological Office this morning confirmed this through an analysis of GPS data.

The deceleration of inflation is an indication that magma pressure is rising, increasing the chances of new dike intrusion and also volcanic eruption. This is a similar change in ground displacement that was observed at the end of the day on December 15, which culminated in an eruption three days later. However, it is difficult to assert whether this pattern will repeat.

The first signs of an impending volcanic eruption are a sudden increase in seismic activity, and such signs were observed shortly before the eruption began on December 18.

In recent days, seismic activity in the area has been relatively consistant, with around 200 earthquakes recorded per day. Most of the earthquakes measure below magnitude 1.0, but around 30 earthquakes with magnitudes exceeding 1.0 have been recorded since December 29, with the largest being a magnitude 2.1 located in the northern part of Grindavík.

Continued scientific assessment indicates that, should an eruption occur, the Sundhnúkur crater row, between Stóra-Skógafell and Hagafell, is the most probable location for an eruption. However, it is important to note that magma migration does not always result in an eruption, as demonstrated by the activity at Fagradalsfjall and in the Krafla Fires.

The hazard assessment map issued by the Meteorological Office onDecember 29 remains unchanged and is valid until January 5.

Seismic activity continues to be measured west of Fagradalsfjall, where around 100 small earthquakes have been recorded since December 29. Further analysis of the monitoring data will soon be conducted to obtain a clearer picture of the situation at Fagradalsfjall.

 

Updated 29 December at 15:15 UTC

The ground continues to inflate at Svartsengi. At the GPS station Svartsengi (SENG), the land has now reached a similar height as measured just before the eruption on 18 December. The rate of uplift since 18 December has remained constant, which is different from the situation before the last eruption, where uplift slowed in the days before the eruption. However, it is difficult to assert that the uplift will slow down before the next eruption, though this has been the case in eruptions on the Reykjanes Peninsula in recent years, and it was also noted during the Krafla Fires. Uncertainty remains about how much magma pressure needs to build up before magma starts moving towards the surface.

The current uplift is not accompanied by as much seismic activity as before. The reason for this is that significant stress in the area was released during the events on 10 November and 18 December. Therefore, considerably more magma needs to accumulate before seismic activity increases from its current level. Before the last eruption, there were several earthquakes over magnitude 3 and one over magnitude 4. Similar seismic activity can be expected in connection with the next magma intrusion.

As magma accumulation continues under Svartsengi, the likelihood of another magma intrusion and an eruption increases with each passing day. It is most likely that the next eruption will occur in the Sundhnúkur, between Stóra-Skógfell and Hagafell. It is important to note that magma intrusions do not always lead to an eruption, as shown by the activity at Fagradalsfjall and in the Krafla Fires.

The Icelandic Meteorological Office has issued an updated hazard map, based on the joint interpretation of data at a status meeting held today, 29 December. The overall assessment of hazard levels within the areas remains unchanged from the last update. However, changes have been made to the list of potential hazards within area 4, Grindavík, where risks due to possible lava flow and gas pollution have been added. The changes are due to increased chances of an eruption north of Grindavík. This hazard map will be reviewed on 5 January 2024.

In the meantime, IMO continues to monitor the area and any changes will be communicated directly to civil protection via the usual communication channels.

Updated 27 December at 14:20 UTC

Since 22 December, around 730 earthquakes have been recorded in the vicinity of the magma intrusion, of which 40 had a magnitude above M1. The largest earthquake over this period had a magnitude of 2.1 on 26 December, north of Hagafell. Most of the earthquakes are occurring at a depth of 4 km. Additionally, between 22 December and today, around 140 earthquakes have been located on the western side of Fagradalsfjall. Five of these earthquakes were above M1 in size and the overall depth range was 4 to 7 km.

Ground deformation continues in the Svartsengi region, and the rate of deformation is now similar to before the eruption on 18 December 2023. This means that magma continues to accumulate under Svartsengi. Therefore, it is increasingly likely that another magma intrusion will occur, possibility leading to a second volcanic eruption. Geodetic modelling results indicate that over 10 million m³ of magma were sourced from beneath Svartsengi to feed the intrusion that formed on 18 December, which led to the eruption. Based on the ongoing uplift rate, it will take one to two weeks for the same amount of magma to accumulate again underneath Svartsengi. There is still significant uncertainty on when the built-up in magma pressure will be sufficient to trigger the next magma intrusion.

It should be noted that the original magma intrusion, which formed on 10 November, extended 15 km from Kálfafellsheiði in the north to the southwest of Grindavík, just offshore. This means that magma propagated at depth beneath the entire area, including the town of Grindavík. However, the most likely source area for the next eruption is between Stóra-Skógfell and Hagafell. Based on insights from the December 2023 eruption, the likelihood for the next event increases day by day. 

The hazard assessment map issued on 22 December 2023 remains valid. Assuming an unchanged situation, a new map will be issued on 29 December.

Time-series of continuous GPS solutions from station Svartsengi (SENG). The graph shows ground displacements in three components over the past 90 days. From bottom to top they are: up, east, and north, all measured in millimetres. The blue, vertical line shows the timing of the 10 November magma intrusion, and the red line the volcanic eruption on 18 December 2023. Each data point represents a 24-hour solution, and the vertical component shows clearly the ongoing ground uplift at Svartsengi.

Updated 22 December at 17:00 UTC

As announced yesterday, the fissure eruption at Sundhnúksgígar has ended. This indicates a temporary cessation of eruptive activity. In the last 24 hours, nearly 90 earthquakes were recorded in the Grindavík, Sundhnúksgígar, and Svartsengi regions. The largest earthquake was M1.6 west of Hagafell, just after 16:00 UTC yesterday (21 December). Overall, seismicity levels are low but variable on a daily basis.

According to GPS and satellite-based measurements, ground uplift in the Svartsengi region was apparent immediately after the eruption began on the evening of 18 December. Initial measurements show that the rate of uplift is greater than before the eruption occurred. This signifies that magma accumulation continues unabated beneath Svartsengi. This development will likely lead to another dike intrusion and, ultimately, a volcanic eruption. In the event of an eruption, the most likely source region is between Stóra-Skógfell and Hagafell.

Continuous GPS measurements show that the rate of daily ground uplift at Svartsengi between 10 November, when the magmatic intrusion formed, and 18 December progressively declined. This process is likely to repeat itself, meaning that the next dike intrusion could begin with little warning when the uplift rate decreases again. Therefore, the likelihood of an eruption increases day-by-day.

Following confirmation of the end of the 18 December eruption, the Icelandic Meteorological Office has issued a new hazard assessment. The hazard map comes into effect at 16:00 UTC today (22 December), and it remains valid until 18:00 UTC on 29 December. The main changes affect zones 2 and 3, where hazard levels have reduced from very high (purple) to high (red). The hazard assessment for all other zones is unchanged. Notably, the assessment for Grindavík is unchanged from the previous map, and the hazard level remains considerable. We emphasise that conditions can change rapidly, and that weather conditions can significantly affect the sensitivity of our monitoring networks. Under such conditions, the warning time could shorten considerably.

The weather forecast for Grindavík on 23 December calls for northeast wind 10-15 m/s, intermittent snowfall, and possibly drifting snow. Temperatures will be low, between 3 to 5°C. On 24 December, winds from the north 13-18 m/s with occasional snow showers, but 10-15 m/s in the afternoon with decreasing snow showers. Intermittent drifting snow can be expected. Temperatures will be from 0 to 2°C

The latest hazard assessment map, published on 22 December, 16:00 UTC. It is important to note that new hazards could arise with little warning within the specified areas. Additionally, the assessment applies only to the specified areas, whereas hazards could extend or occur beyond the identified zones.

Updated 21 December at 12:55 UTC

Scientists who flew over the eruption site this morning confirm that no eruptive activity is visible and that lava flow from the craters seems to have ceased. Glowing is still visible in the lava field, possibly within closed channels. This was also confirmed by an Elfu staff member in Sýlingarfell. The activity appears to have diminished late last night or very early this morning. However, it is still possible that lava is flowing in closed channels, so it is premature to declare the eruption over.

Earthquake activity has continued to decrease, and over the last 24 hours, approximately 70 minor earthquakes were measured over the magma conduits. The largest quake yesterday occurred at 14:27 and measured 1.4 in magnitude, while the largest since midnight last night was magnitude 1.9. Deformation measurements at Svartsengi show little movement, but measurements over the next few days will further clarify the situation there.

Gas dispersion, mainly due to the degassing of the lava field, will be southeastward and out to sea today. Tomorrow, with a slower northeast wind, the gas will travel southwest.

At this point, it is difficult to predict the continuation of the eruption, but scientists at the Meteorological Office are constantly assessing the latest data and continue to closely monitor the area.

Updated 20 December at 18:50 UTC

The eruption that began in the Sundhnúksgígar crater row on 18 December started with considerable force, and the warning period was short. About 90 minutes passed from the first signs of seismicity until the eruption began. The eruption occurred on the magma intrusion that formed on 10 November. The magma is sourced most likely from beneath Svartsengi, where the land has risen repeatedly since 2020.

In the last 24 hours, the highest activity in the eruption has remained around the middle of the fissure that opened on 18 December. Seismic activity has been relatively steady, and there have been little changes in deformation since the eruption began. Considering this, the Icelandic Meteorological Office (IMO) assesses that the likelihood of a new eruption forming without warning nearby Grindavík has decreased. Therefore, IMO has issued a new hazard assessment map that will take effect tomorrow, Thursday, 21 December at 7:00 UTC. The hazard assessment map is valid until 28 December. It should be noted that although the likelihood of vent formation within area 4 has decreased, the hazard level in that area is nevertheless considered substantial. Even though the activity has decreased since the eruption began, the intensity of the eruption is still significant and comparable to eruptions at Fagradalsfjall. It has also been shown that the magma can reach the surface quickly, leaving little time to issue warnings.

Because of the volcanic eruption that began at Sundhnúksgígar crater row on 18 December, there is an increased likelihood of further vent openings on the original fissure. Based on the sudden onset of the eruption at Sundhnúksgígar, the warning time for new fissure openings could be very short.

Updated 20 December at 17:00 UTC

The vigor of the eruption continues to diminish. New images of the area show that currently two craters are erupting. The most active today is the crater directly east of Sýlingarfell which is the southernmost of the craters that were active yesterday.

Lava continues to mostly flow east from the volcanic vents, but a lava tongue has also run west, north of Stóra-Skógfell. The southernmost edge of the lava does not appear to be advancing. Satellite images taken last night show that the lava field is about 3.7 square kilometers in size.

Wind will turn northwesterly tonight and tomorrow, and pollution will be transported southeastward and out to sea. The Icelandic Meteorological Office regularly issues gas pollution forecasts.

There has been a significant decrease in earthquake activity, and over the last 24 hours, about 80 small tremors have been measured over the magma conduits. The largest quake was 2.2 in magnitude at 10:55 am yesterday morning, and the largest since midnight is 1.2 in magnitude.

Updated 19 December at 18:30 UTC

The eruption continues to weaken. New aerial images of the area show that there are now three vents erupting southeast of Stóra-Skógfell, down from the previous five. The lava has mostly flowed east from the eruption site, but there is also a lava tongue flowing west from the region north of Stóra-Skógfell.

Since the eruption began, about 320 earthquakes have been measured over the magma channels. The largest earthquake, with a magnitude of 4.1, occurred at 23:25 on Monday. After midnight, seismic activity significantly decreased, and since 12:00 today, only 10 earthquakes have been recorded in the region. Following the eruption at Sundhnúksgíga, the land in Svartsengi subsided more than 5 cm. Previously, the land had risen there by about 35 cm since the formation of the magma channel on November 10. It is too early to determine if magma will continue to accumulate under Svartsengi and whether the land will start to rise again.

While the eruption continues at Sundhnúksgíga, there is an increased likelihood that more vents may open along the original fissure as well as further north or south. Looking back at the lead-up to the eruption reveals that there were approximately 90 minutes between the first indicators and the start of the eruption. Therefore, the warning time for new vent openings at Sundhnúk could be very short.

Updated 19 December at 14:30 UTC

The size of the volcanic eruption at Sundhnúksgígar continues to diminish. The lava flow is estimated to be about one-quarter of what it was at the beginning of the eruption on 18 December, and a third of the original fissure is active. The lava fountains are also lower than at the start of the eruption, reaching about 30 meters at their highest. These figures are based on visual estimates from a reconnaissance flight early on 19 December.

The development of the eruption is similar to recent eruptions at Fagradalsfjall, where the fissures are starting to contract and form individual eruption vents. Presently, there are about five eruption vents spread along the original fissure.

According to information from scientists who went on a second helicopter flight with the Icelandic Coast Guard at around 04:00 UTC today, the total length of the fissure eruption has not changed much from the beginning. There was little activity at the southern end of the fissure near Hagafell, and the majority of the lava flow is heading east towards Fagradalsfjall. Two streams reach west, both north of Stóra-Skógfell.

At the time of publication, the volcanic plume is drifting from the west and northwest. Gas pollution might be noticeable in Vestmannaeyjar today, but not elsewhere in populated areas. According to the weather forecast, gas pollution might be detected in the capital area late tonight or tomorrow morning.

A new hazard assessment map is being prepared, and it will be published later today.

Amplitude image from an ICEYE satellite acquired at 03:11 this morning (19 Dec. 2023). Preliminary analysis of this image show the new eruptive fissure (yellow line) and lava flow (colored area). Notice that he dams built around Svartsengi are clearly visible.

Updated 19 December at 3:00

The intensity of the volcanic eruption, which started about four hours ago, is decreasing. This is evident from seismic and GPS measurements. The fact that the activity is decreasing already is not an indication of how long the eruption will last, but rather that the eruption is reaching a state of equilibrium. This development has been observed at the beginning of all eruptions on the Reykjanes Peninsula in recent years.

The eruptive fissure is about 4 km long, with the northern end just east of Stóra-Skógfell and the southern end just east of Sundhnúk. The distance from the southern end to the edge of Grindavík is almost 3 km.

The Icelandic Meteorological Office continues to monitor the activity and is in direct contact with civil protection and response units in the area. A meeting of scientists will be held tomorrow morning to evaluate the overnight development of the eruption.

This news will be updated at 09:00 on 19 December.

Updated 19 December at 02:10

According to the latest aerial observations and seismicity, the eruption fissure is expanding to the south. At the time of publication, the southern end of the fissure was close to Sundhnúkur. 

The eruption is located on the dyke intrusion that formed in November. The rate of lava discharge during the first two hours of the eruption was thought to be on a scale of hundreds of cubic metres per second, with the largest lava fountains on the northern end of the fissures. 

Lava is spreading laterally from either side of the newly opened fissures. From real-time GPS measurements, significant ground deformation has accompanied the opening of the eruption fissures. 

Since midnight on 19 December, the level of seismicity at the eruption site has decreased. Additionally, estimates of fissure lengthening suggest that the eruption has decreased in intensity since its onset at 22:17 on 18 December.

Updated 18 December at 23:00

 

At 22:17 this evening, a volcanic eruption began north of Grindavík on the Reykjanes peninsula. The eruption is located close to Sundhnúkagígar, about four kilometres northeast of Grindavík, and it can be seen on nearby web cameras. The eruption was preceded by an earthquake swarm that started at 21:00.

 

A Coast Guard helicopter will take off shortly to confirm the exact location and size of the eruption.

More information will be available soon.

Updated 16 December at 14:00 UTC

At this stage it is too early to say if magma accumulation at Svartsengi has stopped and the inflation is over. The rate of deformation has decreased somewhat in recent days, but more data is needed to interpret the possible development of the activity in Svartsengi.

Scientists will continue to analyze the data in the coming days. 

A new hazard map will be released on Wednesday December 20th, which will reflect the interpretation of the latest data.

Updated 15. December at 13:00 UTC

Generally weak seismicity continues in the area affected by the dike and is mostly concentrated near Hagafell.  Since Tuesday December 12, 460 earthquakes, 30 of which were greater than M1.0, have been measured. The largest earthquake in this time was M2.8 near Hagafell on Tuesday morning. Data from GPS stations and satellite images show that uplift due to the accumulation of magma continues around Svartsengi. While magma continues to accumulate in this area, further dikes or an eruption remain possible.

The hazard map published on December 6 Icelandic map here below continues to be valid until December 20. Conditions inside and outside the demarcated hazard zones can change with little warning.

Updated 13. December at 11:15 UTC

The area around Svartsengi continues to inflate. The rate of inflation has decreased somewhat since Friday, but it is still greater than it was prior to the formation of the dike that traveled under Grindavík November 10 .

While magma continues to accumulate around Svartsengi, further dikes or an eruption remain possible.

If another dike forms it is considered to be likeliest that it would follow the same path as the November 10 dike. The most likely location for a potential eruption under these conditions is assessed to be north of Grindavík in the direction of Hagafell and the area around Sundhnúkagígar. 

Seismic activity continues at a similar level to the previous days. It is generally weak and mostly in the area around Hagafell.

Updated 6. December at 18:00 UTC

Latest geodetic modelling results suggests that the magma inflow to the dike that formed on November 10 has likely ceased. The chances of an eruption happening along the dike at this time have therefore significantly decreased. However, magma accumulation continues beneath Svartsengi.  

The ongoing activity at Svartsengi, which began in October, is not yet over and a new chapter may have begun with an increased chance of a new magma propagation and, subsequently, increased likelihood of an eruption. 

As previously mentioned, the dike beneath Grindavík was fed by magma accumulating beneath Svartsengi. It is likely that this sequence of events will repeat. When looking at the overall pattern with repeated magma accumulation, it can be estimated that the next magma propagation from Svartsengi might be on a smaller scale than the one previously formed on November 10. A magma propagation could persist for several hours or days with an increased risk due to seismic activity and deformation during that period. 

Signs of a magma propagation include a sudden increase in seismic activity and rapid changes in ground deformation. These signs can be observed on instruments several hours before the magma propagation is likely to pose a threat to Svartsengi or Grindavík. If a magma propagation occurs, the Icelandic Meteorological Office will immediately activate response plans for public safety. 

Following a magma propagation, the likelihood of an eruption increases. As mentioned above, it is most likely that magma will propagate from Svartsengi into the previously formed dike on November 10. Making it the most likely area for an eruption. 

It is not possible to estimate when the next magma propagation will occur. The uncertainty is considerable, and a magma propagation could happen in the next few days or possibly after several months. 

The Icelandic Meteorological Office continues to monitor the area closely and continues to monitor any signs of magma propagation and other changes that could pose further danger in the area near Svartsengi and Grindavík.

Comparison of Svartsengi and Krafla Fires

In the last week, approximately 300-500 earthquakes were detected in a 24-hour period around the dike intrusion. The largest earthquake was a M2.7 near Hagafell on Friday evening. Since midnight today, about 90 earthquakes have been detected along the dike, all measuring below a M2.0. The majority of seismic activity continues to be concentrated along the middle of the dike at about 3-4 km depth. Due to subsidence in Svartsengi the stress in the Earth’s crust has changed. Until the previous stress level is reached, it can be expected that minor seismicity continuous in the region.

Despite the recent decrease in seismic activity in the last weeks, further unrest can be expected on the Reykjanes Peninsula. Examples of similar unrest can be seen in the Krafla Fires that began in 1975. Over a 10-year period, there were 20 magma propagations, with 9 of them resulting in an eruption (see explanatory image below). In the Krafla Fires, all of the magma propagations fed the same dike but they varied in size. A similar recurrence can also be observed in the activity around Fagradalsfjall.

De seneste geodætiske modelleringsresultater indikerer, at mængden af ​​magma, der i øjeblikket er akkumuleret under Svartsengi, er betydeligt mindre end volumen akkumuleret før digets indtrængning den 10. november. Når man ser på magma-akkumuleringen og magma-udbredelsen i Krafla-brandene, er det tydeligt, at den største mængden af ​​magma havde ophobet sig i Krafla-calderaen før det første vulkanudbrud. En mindre mængde magma akkumulerede i calderaen, før den næste magma-udbredelse fandt sted. Det kan estimeres, at en lignende udvikling vil ske i forhold til magmaophobning under Svartsengi, og der skal ophobes en mindre mængde magma, før den udløser den næste magmaudbredelse ind i diget. Det er sandsynligt, at langsomt stigende seismicitet vil blive opdaget, før en ny magmaudbredelse finder sted, hvilket indikerer øget tryk under Svartsengi.

Billedet viser samspillet mellem dannelsen af ​​diger og løft midt i Krafla-krateret. Det nederste billede viser højden af ​​land inden for Krafla-krateret, mens det øverste viser afstanden mellem Krafla-krateret og urolighederne. (Páll Einarsson og Bryndís Brandsdóttir, 2021)

Opdateret 1. december kl. 16:50 UTC

 

Seismiciteten på halvøen fortsætter med at falde. I de sidste par dage har det automatiske jordskælvslokaliseringssystem registreret relativt få jordskælv, for det meste mikrojordskælv under størrelsesordenen 1. Den seneste seismicitet er koncentreret i området mellem Sýlingarfell og Hagafell, hvor diget højst sandsynligt fødes af magma, der ophobes under Svartsengi. Nogle deformationer detekteres stadig på cGPS-stationerne tæt på diget, men signalet tolkes nu hovedsageligt som skorpens reaktion på den igangværende inflation i Svartsengi-området.

Selvom aktiviteten langs diget og dets omegn nu foregår med meget lav intensitet, fortsætter inflationen, som startede i Svartsengi få dage efter digets dannelse, med et nogenlunde stabilt tempo. Nogle cGPS-stationer omkring Svartsengi og Mt. Þorbjörn viser en langsom faldende tendens, men andre stationer viser stadig en konstant tendens, hvilket tyder på, at indstrømningshastigheden af ​​magma i dybden ikke er reduceret væsentligt.

Processen, der begyndte den 25. oktober med en betydelig seismisk sværm og toppede den 10. november med dannelsen af ​​et 15 km langt magmatisk dige, er ikke slut. Med sikkerhed kan det konstateres, at en fase er startet, hvor et lignende hændelsesforløb kan gentage sig med tiden.

På dette stadium er det dog svært at sige, hvornår den næste energiske indtrængen af ​​magma på lavere dybde kan forekomme, og om den vil forekomme i et lignende område eller ej. IMO fortsætter med at opretholde overvågningen af ​​området på et højt niveau.

 

Opdateret 29. november kl. 17:00 UTC

The seismic activity has continued to slowly decrease over the last two days. Yesterday, about 340 earthquakes were measured near the magma intrusion in the area east of Sýlingarfell, and since midnight today, around 150 earthquakes have been recorded. Most of the earthquakes have been smaller than magnitude 1.0.

The rate of uplift near Svartsengi has been decreasing, but it is still ongoing at a rate of about 1 cm per day. The majority of the displacement in the region is currently attributed to inflow under Svartsengi with a smaller portion flowing into the magmatic intrusion. In other words, the deformation measured and modeled at Svartsengi is now much greater than that seen near the magma intrusion, but all deformation signals are slowly diminishing. Observed signs of inflow into the magmatic intrusion is now limited to the area east of Sýlingarfell. Despite the slowing down of seismic activity and deformation, an eruption is still considered to be possible. If an eruption does occur, the location thought to be most likely is east of Sýlingarfell.

Here is a timeline for the GPS station Svartsengi (SENG). It shows movements over the last 90 days in the north, east, and vertical directions. The blue line marks the magma intrusion from November 10th until today.

This image depicts the movements from the station since November 10th until today.

Updated 27. November at 16:30 UTC

Seismic activity has been relatively stable for the past few days with a daily rate of about 500 earthquakes in the area of the magmatic dike. Most of the seismicity continues to be nearby Sýlingarfell and Hagafell. Around midnight a short-lived seismic swarm commenced in the vicinity of Sýlingarfell and lasted for roughly one hour. A total of 170 earthquakes were detected in the area at a depth of 3-5 km. The earthquakes were almost all very small with one M3.0.

Data from GPS stations and satellite images show that uplift continues in the area of Svartsengi and deformation is still ongoing along and around the dike. The elevated seismic activity which occurred around midnight isn´t associated with any changes to the ongoing deformation. Both seismic and deformation data suggest that magma continues to accumulate beneath Svartsengi and to flow into the middle portion of the dike which formed on 10 November. The seismic swarm that occurred this night might indicate increasing pressure within the dike.

In light of the available data and the newest analysis, an eruption along the dike is still considered likely as long as the magma inflow continues. It is assessed that the area with the highest likelihood for an eruption is in the middle part of the dike between Hagafell and Sýlingarfell. The hazard map published by the IMO on 22 November remains valid.

Additional geodetical modelling has been performed to reconstruct the evolution of the dike which formed on 10 November. These newest results suggest that the dike at depth could be wider than  initially assessed. The time needed to solidify the magma that intruded into the dike would be therefore estimated to be on the order of a few months.

This picture shows reviewed earthquakes since 24. November.

Updated 24. November at 13:30 UTC

Yesterday, around 650 earthquakes were measured near the dike intrusion north of Grindavík, and since midnight today, nearly 300 earthquakes have been detected. Most of the earthquakes are below M1.0, but the largest earthquake in the last two days was M2.7 near Hagafell. The seismic activity continues to decrease.

Data from GPS measurements show that deformation continues near Svartsengi, and deformation is still measured around the dike intrusion. However, there are indications that the rate of deformation has decreased based on data from the past week. Though, the interpretation of deformation data is complex at this stage. This is because other processes, such as fault movements related to earthquakes and the viscoelastic response of the Earth’s crust to unrest in the area, have an impact on the deformation signals.

Considering the latest interpretation of all data, the likelihood of a volcanic eruption at some location along the length of the magma intrusion persists. It is possible that magma could emerge in the area between Hagafell and Sýlingarfell. However, as crustal relaxation continues to occur and seismicity decreases, along with a decrease in magma inflow to the intrusion, the likelihood of an imminent volcanic eruption diminishes with time.

Overview of seismic activity from Friday, November 17th. The upper graph shows the number of earthquakes per hour, and the lower graph shows the number of earthquakes per day. The effects of strong wind and heavy sea swell on the Reykjanes Peninsula on November 21st and 22nd are evident in fewer recorded earthquakes due to reduced sensitivity of the seismic network during that time.

Updated 23. November at 12:30 UTC

On 21 November, approximately 300 earthquakes were detected in the region of the magma intrusion. From midnight on 22 November to 18:00 UTC on the same day, around 100 earthquakes had been recorded in the same region, which is considerably less than in recent days. Additionally, the intensity of earthquakes above magnitude 2.0 has decreased. During the period of severe weather on 21 and 22 November, efforts were made to assess how weather conditions and ocean swell influences IMO’s monitoring systems.

Magma inflow rates and crustal adjustments related to the formation of the intrusion continue to diminish. Additionally, crustal uplift near to Svartsengi continues at a similar pace. Geodetical models based on data from 21 November suggest that the influx into the intrusion is greatest near to the Sundhnúkur crater row, about 4 km northeast of Grindavík. Minor surface displacements have been detected within the graben region in and around Grindavík.

The likelihood of a volcanic eruption at some location along the length of the magma intrusion persists. It is possible that magma could emerge in the area between Hagafell and Sýlingarfell. However, as crustal relaxation continues to occur and seismicity decreases, along with a decrease in magma inflow to the intrusion, the likelihood of an imminent volcanic eruption diminishes with time.

Based on the latest data, and considering the evolution of activity since 10 November, the likelihood of a sudden eruption within the Grindavík urban area is decreasing daily, and it is presently assessed as low. It can be assumed that newly emplaced magma beneath Grindavík has solidified partially, thereby reducing the likelihood that the magma will reach the surface within the city limits. However, we emphasise that the possibility of a volcanic eruption at some point along the length of the intrusion, particularly between Hagafell and Sýlingarfell, remains plausible.

It is apparent that there is a strong connection between crustal uplift in the Svartsengi region and the sudden, initial propagation of the magma intrusion on 10 November. Models indicate that the magma in the reservoir beneath Svartsengi may have flowed eastward towards the Sundhnúkur craters, subsequently forming the 15-km-long volcanic intrusion. While crustal uplift in Svartsengi continues, it is expected that the accumulating magma may flow again eastwards, potentially reactivating the intrusion. It is also feasible that a magma intrusion could form to the west of the magma body accumulating beneath Svartsengi. Precursors to such an event would include pronounced seismicity and rapid ground displacements, both of which are monitored closely by IMO continuously.

Updated 21. November at 15:30 UTC

 

Since midnight today, 165 earthquakes have been recorded due to the ongoing volcanic unrest, all below magnitude 2.0 in size. The level of seismicity today is considerably lower than in the recent days, when 1,500-1,800 earthquakes were recorded each day. It can be expected that the intense weather affecting the country has an impact on the sensitivity of the seismic monitoring system to detect the smallest earthquakes, making it difficult to assess whether the seismic activity is decreasing overall.

The deformation associated with the magma intrusion that formed on November 10 continues. Likewise, crustal uplift continues near Svartsengi. The speed of the uplift at Svartsengi has remained almost the same during the past 24 hours.

In collaboration with specialists from the University of Iceland, IMO continues to monitor the area as effectively as possible, constantly re-evaluating and interpreting the data received.

As mentioned before, IMO has increased surveillance in and around Grindavík and the area around Hagafell. The effectiveness of this surveillance depends on the high sensitivity of earthquake and real-time GPS measurements, which are highly dependent on weather conditions. Given the weather forecast for the next two days, which indicates precipitation and significant wind, it can be expected that both seismic monitoring and real-time GPS observations will be affected. Ocean waves also create microseisms that overwhelm the low-frequency detection capabilities of seismometers on the Reykjanes Peninsula. Fog and hail showers could also affect the visual confirmation of an eruption, adding to the monitoring and assessment uncertainty.

 

Updated 20. November at 13:20 UTC

Since midnight today, over 700 earthquakes have been detected in the region of the magma intrusion, the largest of which was magnitude 2.7 near to Hagafell. 

In recent days, between 1,500 and 1,800 daily earthquakes have been measured in the region, with the largest event registering magnitude 3.0 last Friday (17 November). Based on radar imagery from 18 and 19 November 2023, the latest interferogram of the magma intrusion and the surrounding area shows significant crustal uplift in the vicinity of Svartsengi. The newly processed interferogram was reviewed by experts during the weekend (18 – 19 November) from the Icelandic Meteorological Office, the University of Iceland, and the Department of Civil Protection and Emergency Management. The results were also discussed in today’s status meeting, held at IMO. The rapid, ongoing uplift close to Svartsengi is occurring in the same area where uplift was measured before the magma intrusion formed on November 10. Geodetic models derived from satellite images show that the uplift in Svartsengi area is considerably faster than before. Generally, when a magma intrusion forms, subsidence occurs above the centreline of the intrusion, as seen in Grindavík, with signs of land uplift discernible adjacent to the intrusion. Crustal uplift in the Svartsengi region due to magma accumulating at depth has been measurable since the intrusion began to form on 10 November. Initially, the uplift sign was influenced by the formation of the intrusion, but now the dominance of deep magma recharge is apparent.

The clear sign of crustal uplift in Svartsengi region does not change the likelihood of an eruption from the magma intrusion. This is assessed, amongst other things, on the fact that the Earth’s crust over the magma intrusion is much weaker than the crust over the uplift region close to Svartsengi. As long as there is not significant seismicity in the Svartsengi region, there is not a high likelihood of an eruption at that location. Moreover, an eruption is still deemed more likely from the intrusion, particularly if there is a sudden, large inflow of magma into the intrusion.

Our monitoring and hazard assessment preparations are still based on the assumption that the situation could change suddenly with little warning. The Icelandic Meteorological Office, in close cooperation with experts from the University of Iceland, will continue to monitor the area closely, with the goal of continually interpreting and evaluating all available monitoring observations.

COSMO-Skymed interferogram spanning 24-hours between 18−19 November at 06:41. The broad uplift signal visible in orange/red around Svartsengi is indicative of a deep inflation (>5 km) taking place.

Updated 18 November at 15:00 UTC

Seismicity related to the magma intrusion that formed suddenly a week ago remains high and constant. Approximately 1,700 earthquakes have been recorded in the last 24 hours, 1.000 of those recorded since midnight. The largest earthquake during the last 24 hours had a magnitude of 2.8 and occurred near Hagafell, 3.5 km NNE of Grindavík.

Updated 17 November at 12:00 UTC

Seismicity related to the magma intrusion that formed suddenly a week ago remains high and constant, although the level of activity is substantially lower than 10 – 12 November 2023. Approximately 2,000 earthquakes have been recorded in the last 24 hours, with most activity in an area north of Hagafell, towards the Sundhnúkar craters. Most of the seismicity is micro-earthquake activity comprising earthquakes under M 1. The largest earthquake during the last 24 hours occurred at 06:35 near Hagefell; it had a magnitude of 3.0.

According to GPS measurements, ground deformation continues but at a decreasing rate. The latest geophysical models based on GPS data and satellite imagery indicate that the largest movements in the magma intrusion are occurring north of Grindavík, near Hagafell. If magma manages to reach the surface, Hagafell is thought to be a prime location for an eruption.

Subsidence over the magma intrusion remains active, although measurements show a slight slowdown from day to day. Presently, GPS stations located in and around Grindavík, near the center of the subsidence zone, show about 3–4 cm of subsidence per day.

Based on the interpretation of the latest data and model results, a volcanic eruption remains likely, with the highest likelihood of it starting north of Grindavík near Hagafell.

A map showing the extent of the subsidence over the magma instrusion in and around Grindavík. A GPS station (GRIC) located near the center of the subsidence has recorded a total subsidence of 25 cm since the beginning of the event.

 

Updated 16 November at 17:50 UTC

Over the past few days, seismicity near the magma intrusion has remained relatively stable. As of 17:00 today, about 1,400 earthquakes have been recorded since midnight, the largest being 2.9 in magnitude, sourced near Hagafell just after 13:00. Most of the earthquakes were under magnitude 2, with the highest concentration of activity near Hagafell.

Deformation related to the magma intrusion continues to be measured, although it has slowed slightly since yesterday. The latest models, derived from GPS measurements and satellite data, still suggest that the largest movements of the magma intrusion are north of Grindavík near Hagafell. If magma manages to break through to the surface, it is most likely to happen in the region of Hagafell.

Eartly today, sulphur dioxide (SO₂), a type of volcanic gas, was measured from a borehole at Svartsengi, located just north of Þorbjörn. The borehole extends eastward to considerable depth towards the Sundhnúkur crater row. The base of the borehole therefore reaches close to the location in the crust was the magma intrusion is located. Further gas measurements will be conducted tomorrow, 17 November. The detection of volcanic gas from such a borehole is another independent confirmation of the presence of magma north of Hagafell, as indicated by seismic activity and geophysical modelling results.

The likelihood of an eruption remains high. Monitoring continues for signs of shallowing seismicity and sudden crustal movements, which could be precursors to magma breaking its way to the surface. At the time of writing, no such signs had been observed.

Updated 15. November at 11:30 UTC

Since midnight, about 800 earthquakes have been measured, most of them in the middle of the magma dyke at Sundhnúk at a depth of about 3-5 km. Seismic activity has remained constant since 11^th of November. The main monitoring focus on seismic activity remains in the area of ​​the dike and Grindavík.

Deformation measurements show continued deformation in the area. They are consistent with magma still flowing into the dyke. Part of the magma dyke seems to be solidifying, especially at the edges, but not at the magma inflow area, which is believed to be near Sundhnúk.

Measurements of sulfur dioxide (SO₂) seem to show fluctuating degassing due to the magma dyke, but further measurements are needed for confirmation. Analysis of this data is currently underway in collaboration with the Chalmers University in Sweden.

The fiber optic cable of HS Orka, that runs from Svartsengi west of Þorbjörn to Arfadalsvík is beeing used as a continuous seismic measuring line with high sensitivity. This is a new technology that has developed in recent years and is now used as additional measurements in collaboration with HS Orku and ETH in Switzerland.

Overall, the situation seems to be unchanged since yesterday. The probability of an eruption is still considered high. In the event of an eruption, the most likely location is at the magma dyke.

Updated 14. November at 19:20 UTC

Earlier this week, IMO specialists installed two DOAS remote sensing instruments on Húsafell. These instruments can measure the presence and the amount of SO2 in the atmosphere. One of the DOAS instruments detected SO2 yesterday and today at the newly formed graben, located between Sundhnúkagígar and Grindavík. Because of the low amount of daylight, the measurements can be imprecise, and it took time to review the data and interpret it. In the last two days, eastern winds have been prevalent in the area, so it cannot be ruled out that recent strong seismicity has caused the release of SO2 from beneath Fagardalsfjall, as magma at that location has not solidified yet since the eruption in July 2023.

It is hard to estimate the depth from which the SO2 is being released as the process is influenced by magma pressure. However, it is thought that the magma needs to be in the upper hundred meters of the crust in order for SO2 to be released. This is one of the reasons why the DOAS instruments have been sited close to Grindavík.

DOAS (Differential Optical Absorption Spectrometer) is a tool that can detect sulfur dioxide in the atmosphere. The method relies on visible light, which travels through the atmosphere, hits a sensor in the measuring device, which is then analyzed for certain colors (wavelengths) that are missing from the spectrum. Sulfur dioxide absorbs certain wavelengths of light, which means that light hits the measuring instrument in a different way if SO2 is detected. The probe scans certain sectors of the sky, and it provides information on the concentration of sulfur dioxide within the area scanned. DOAS measurements need daylight to work, so operating such instruments in the wintertime in Iceland can be challenging.

Updated 14. November at 12:40 UTC

Since midnight, 14 November, over 700 earthquakes have been located along the orientation of the magma intrusion, the largest of which was M 3.1 near to Hagafell. Last night, 13 November, stress-triggered seismicity occurred close to Kleifarvatn, with the largest earthquake registering M 3.8 at 21:09 UTC. Today, most earthquakes are occurring along the magma intrusion, with the majority being micro-earthquakes, commonly at focal depths of 3 to 5 km.

Deformation measurements, including high-resolution aerial observations, satellite radar imagery, and ground-based GPS observations reveal continued, ongoing ground movements due to the ongoing formation of the magma intrusion. These results are consistent with continued, albeit much lower magma inflow to the region of the intrusion.

Between 12 and 13 November, the inflow is estimated at 75 m³ / s, and the average depth to the top of the magma intrusion is thought to be around 800 m. The inflow and depth estimates are derived from model-based calculations, and they are subject to uncertainty.

Throughout this period of volcanic unrest, the focus has been continuous monitoring of seismicity and ground deformation in the Grindavík – Svartsengi region. To further our monitoring capabilities, we have installed additional GPS stations in and around Grindavík. The latest measurements from these stations show that the graben-like formation is still forming and mechanically active. Furthermore, to increase our ability to warn of an eruption, we have installed ground-based SO2 detectors that overlook Grindavík and south of Sundhnúkur.

In summary, the likelihood of an eruption remains high. If an eruption occurs, the most likely location with be along the orientation of the magma intrusion, beginning as a fissure eruption.

Updated 13. November at 16:20 UTC

 

Seismicity along the magma intrusion continues, although the size and intensity of the activity is decreasing. Since midnight today, 13 November, around 900 earthquakes have been detected. The seismic activity is concentrated on the region of the intrusion, between Sundhnúkur and Grindavík at a depth of about 2–5 km.

Decreasing rates of ground deformation are seen in GPS data from Grindavík. Satellite radar results show a graben-like formation that cuts through part of Grindavík. This feature was first identified by IMO in satellite radar imagery early on 11 November.

 

This ascending COSMO-SkyMed (CSK) interferogram covers the time period 3-11 November and shows an extensive deformation field related to the dike intrusion that began on the afternoon of the 10 November within the Reykjanes-Svartsengi volcanic system. This CSK interferogram and the previous (spanning 2-10 November) supported the difficult decision made by Civil Protection to evacuate the town of Grindavík late Friday evening. It also enabled modelling of the dimensions of the dike intrusion (on the 11 November), which provided a median dike length of 15 km and top depth of less than 1 km below the surface. The imagery shows over 1-m of ground displacement in the western part of Grindavík, caused by the propagation of the magma intrusion. From geodetical modelling results, we infer that (as of 12 November) the greatest area of magma upwelling is sourced close to Sundhnúkur, 3.5 km north-northeast of Grindavík.

New geodetic modelling is currently being undertaken, using an ICEYE interferogram and GNSS observations spanning the last 24-hours, to better assess the ongoing activity and provide an estimate of the current magma inflow rates.

According to our latest estimates, the volcanic hazard assessment in and around Grindavík is unchanged from 12 November. All monitoring systems are being monitored closely in real-time, especially near Grindavík, for any indications of sudden change. The natural hazards monitoring team at IMO is operating at maximum surveillance while the Department of Civil Protection and Emergency Management coordinates short-term, temporary access to Grindavík today, 13 November.

Estimate of the vertical displacements caused by the dike during its initial propagation from Friday afternoon to Saturday morning. The displacements were estimated by combining ICEYE and COSMO-SkyMed pixel offset tracking results.

Updated 12. November at 12:30 UTC

 

Since the morning of November 11th, seismic activity related to the magma intrusion remains fairly constant. Since midnight November 12th, around 1000 earthquakes have been recorded within the dyke, and all of them have been below M3.0 in magnitude. The most seismic activity has been located in the region north of Grindavík. Most of the earthquakes are at a depth of 3-5 km corresponding to the lower part of the dyke intrusion.

GPS measurements covering the past 24 hours show that deformation associated with the dyke intrusion that formed on Friday, November 10th has slowed. This can be an indication that magma is moving closer to the surface, new models will be run as soon as new data comes in to update the model.

It was a joint assessment from the meeting, based on the latest data, that there is scope for temporary measures under the control of the Department of Civil Protection and Emergency Management to collect necessities for the residents and attend to urgent errands in Grindavík and the surrounding area. During such operations, it is necessary to increase the vigilance of the area through additional monitoring with the aim of improving the detection of magma reaching the surface. It was the opinion of the scientists that it would be advisable to start these operations immediately, as uncertainty about the progress of the event grows as the day progresses. The final decision on whether these actions will be taken, and their implementation is in the hands of public safety and the Police Chief in Suðurnes.

In light of this joint assessment has the Police Chief in Suðurnes decided to allow inhabitant to part of restricted area in Þorkötlustaðahverfi and it is only to retrieve vital items, pets and livestock. This will be organised and controlled operation by the Police. This permission only applies to Þorkötlustaðahverfi. Note, special operation is ongoing to pick up all horses in the area north of Austurver.  

 

 

This news has been updated since the latest information from the Police Chief in Suðurnes.

Updated 11. November at 18:30 UTC

At 18:00 today, 11 November, a status meeting concluded between scientists at the Icelandic Meteorological Office, the University of Iceland, and the Department of Civil Protection and Emergency Management. The purpose of the meeting was to discuss the latest measurements of seismicity and ground deformation in the region of Grindavík, in addition to reviewing the latest geophysical models and hazard assessments. From combined assessments of satellite radar imagery, ground-based GPS measurements, and seismicity, it was concluded that the ongoing dike intrusion represents a serious volcanic hazard. 

From geophysical models of the dike intrusion, it is estimated that the intrusion is propagating upwards slowly, with magma thought to be 800 m beneath the surface. The exact location of a possible eruption site is unknown, but the 15-km length and orientation of the dike gives a good indication of possible sources. The overall assessment from the status meeting was that the likelihood of a volcanic eruption is high, and that an eruption could be possible on a timescale of just days. Based on the extent of the dike, magma could emerge from its southern, just outside of Grindavik. Therefore, the likelihood of a submarine eruption has also increased, so preparations must be made for the possibility of explosive activity. A hazard area has been defined based on the location of the dike, as shown in the map.

Status map showing the location of the dike intrusion based on combined satellite radar imagery, GPS measurements, and geophysical modelling.

Updated 11. November at 12:00pm

 

Since midnight, around 800 earthquakes have been measured in the region where the magma intrusion is occurring. The earthquake activity has diminished slightly in the past hours, but it remains high. Most of the recent earthquakes have occurred close to Grindavík, where the southwest end of the magmatic dyke is estimated to be located.

Analysis of the earthquakes from today and yesterday is ongoing. The goal of this work is to better understand the evolution of the magma intrusion. Presently, the data indicates that the magma intrusion extends from Stóra-Skógsfell in the north to Grindavík in the south, where it extends beneath the sea. In accordance with the latest preliminary models, using the most recent satellite data acquired last night, the shallowest depth of the top of the magma intrusion north of Grindavík is 1.5 km. Joint interpretation of the ground and satellite measurements indicate that the size of the magma intrusion and the rate at which it is moving are several times larger than have been measured previously on the Reykjanes Peninsula. Our assessment is that an eruption, if it were to occur, will originate from the northern side of the magma intrusion. This means that there is a greater likelihood of an eruption beginning close to Sundhnjúkagígur.

Scientists are meeting regularly to interpret the data and update the latest models and hazard assessments. A meeting for journalists will be held at 12:00 at the Department of Civil Protection and Emergency Management. The current conditions and future scenarios will be discussed.

The likelihood of a volcanic eruption occurring in the near future is deemed considerable.

 

Reviewed earthquakes since 9pm last night.

Updated 10. November at 11:30pm

 

Significant changes have occurred in the seismic activity measured near Sundhnjúkagígar north of Grindavík and deformation observed in the Reykjanes Peninsula this afternoon. The seismic activity has moved south towards Grindavík. Based on how the seismic activity has evolved since 6 PM today, along with results from GPS measurements, there is a likelihood that a magma intrusion has extended beneath Grindavík. In light of this outcome, the police chief in Suðurnes, in cooperation with the Civil Protection Authorities, has decided to evacuate Grindavík. An emergency level of civil protection is now in effect. This is not an emergency evacuation. Residents of Grindavík are advised to proceed with caution.

At this stage, it is not possible to determine exactly whether and where magma might reach the surface. There are indications that a considerable amount of magma is moving in an area extending from Sundhnjúkagígum in the north towards Grindavík. The amount of magma involved is significantly more than what was observed in the largest magma intrusions associated with the eruptions at Fagradalsfjall. Further data is being collected to calculate models that provide a more accurate picture of the magma intrusion. It is currently not possible to say when this work will be completed.

 

Updated 10. November at 8pm

 

The seismic activity currently measured at Sundhnjúkagígar occurs within an area about 3 km northeast of Grindavík. The shallowest earthquakes measured now are at a depth of about 3-3.5 km.

The signs that can be seen now at Sundhnjúkagígar are similar to those seen on the eve of the first eruption at Fagradalsfjall in 2021 and are very similar to the seismic activity that was measured about a month before that eruption. The most likely scenario now, taking into account the activity that culminated in the onset of the March 19^th 2021, is that it will take several days (rather than hours) for magma to reach the surface. 

 

Earthquakes on the 10th of November (until 6:48pm). The Icelandic Meteorological Office’s seismic network is shown with triangles. Four seismic stations surrounding the current seismic activity have been showing a large increase in tremor since 3pm.

Updated 10. November at 6:30pm

 

The National Commissioner of the Icelandic Police, in consultation with the Police Commissioner of Suðurnes, has declared a Civil Protection Alert Phase due to the intense earthquake swarm that commenced 3pm today at Sundhnjúkagígar, north of Grindavík. There is the possibility for larger earthquakes than have been experienced thus far, and this sequence of events could lead to an eruption. The Civil Protection Alert Phase means that the risk is increasing, and measures are being taken to ensure the utmost safety of those who live/stay in the area. This is done by increasing precautions in the relevant area.

The Aviation Color Code has been elevated to orange (heightened unrest with increased likelihood of eruption). IMO is closely monitoring the situation. Residents are encouraged to follow the information provided on Almannavarnir.

 

Updated 10. November at 2pm

 

Earlier today, at 12:44, an earthquake of magnitude 4.1 occurred near Sýlingarfell, west of Sundhnjúkagígar. The craters are about 2-3 km northeast of Grindavík. A dense swarm of earthquakes began around 07:00 this morning in the same area, and nearly 800 quakes have been recorded since midnight, including 9 greater than magnitude 3. The depth of the earthquakes is about 5 km. Such earthquake swarms have previously been recorded in this area. It cannot be ruled out that the seismic activity near Sundhnjúkagígar is due to magma movements at depth.

Magma accumulation continues near Þorbjörn at the same depth and at a similar rate as before. It is accompanied by swarm-like seismic activity, as was noticed yesterday and this morning. While magma accumulation continues, ongoing seismic activity can be expected due to stress release in the area. Earthquakes up to magnitude M5.5 can be expected in such swarms, and the seismic activity may shift between areas. At this stage, there are no indications that magma is forcing its way to the surface.

 

Reviewed earthquakes since midnight

Updated 9. November at 12:20pm

 

Around 1400 earthquakes have been recorded in the last 24 hours. Seismic activity increased from midnight, and the SIL seismic network has detected seven earthquakes above M4.0 since then. The largest earthquake measured M4.8 at 12:46am. It was located west of Þorbjörn. It is the largest earthquake since the activity began on October 25th. Seven earthquakes M4.0 or larger in size were measured in the area from Eldvörp to the area east of Sýlingarfell. While the accumulation of magma continues, seismic activity can be expected on the Reykjavík Peninsula because the magma intrusion causes increased tension in the area.

According to GPS data at midnight, uplift continues in the area. The GPS data is being reviewed in relation to the seismic activity tonight. Since the beginning of the inflation until today, the uplift has been fairly even, although an acceleration of the process has been observed between days. The seismic activity last night and this morning is an example of this episodic seismic activity that can be expected while magma accumulation is in progress. The fact that there are now larger earthquakes than before in the area does not necessarily mean an increased rate of magma accumulation.

 

Reviewed earthquakes since midnight last night

Updated 8. November at 2:40pm

 

Approximately 1200 earthquakes have been measured in the last 24 hours, most of them in the area between Þorbjörn and Sýlingafell, similar to the day before. The largest earthquake was M3.4 at 12:31am last night, just south of Þorbjörn. The seismic activity continues at the same depth as before. It is likely that seismic activity will continue, and be episodic in intensity, while magma accumulation is ongoing. 

Uplift continues at a similar rate as before according to Satellite and GNSS data. Interferogram (InSAR) for the period 28th of October – 6th of November showing near-vertical motion confirms this, but it also shows offsets due to fault movements associated with the seismic activity. Updated models based on the same data estimate that magma continues to accumulate in a horizontal sill at a depth of about 5 km and since the beginning of the inflation event (October 27th) the average inflow is estimated about 5 m³/s (uncertainty is ±2 m³/s)

 

Interferogram (InSAR) for the period 28th of October – 6th of November shows that deformation in that period is around 7 cm. SW of Mt. Þorbjörn is an offset in the deformation signal caused by fault movements by earthquakes.

Updated 7. November at 1:30pm

 

There have been around 900 earthquakes in the last 24 hours, most of them in the area between Þorbjörn and Sýlingafell. The largest earthquake was M2.9 and occurred around 7 am this morning. The seismic activity remains at the same depth as before.

According to satellite data processed around 5 pm yesterday and covers the period between November 4-6, confirms that uplift continues around Þorbjörn. The same data shows no signs of magma accumulation in Eldvörp or near Sýlingarfell, east of Svartsengi where seismic activity has been measued in recent days.

Magma accumulation continues at a depth of around 5 km in the are NW of Þorbjörn. If October 27th is considered the starting day of the inflation event until today, the rate of uplift has been fairly constant, although an acceleration of the process has been observed between days. It is likely that seismic activity will continue, and be episodic in intensity, while magma accumulation is ongoing.  

 

Reviewed earthquake locations since 6th of November and today until noon.

Updated 6. November at 1:15pm

 

In the last 24 hours around 1300 earthquakes have been detected on the Reykjanes peninsula, of which three earthquakes were above M3. The largest earthquake was M3.6 this morning and located 3 km NE of Mt. Þorbjörn.

Deformation data shows that uplift continues in the area and there are indications on GNSS observations of an increase in inflation rates since 3rd of November. Since the start of the inflation, the uplift at the GNSS station at Mt. Þorbjörn has reached 7 cm. The deformation is caused by a sill-type intrusion at around 5 km depth. Modelling, based on data since 27th of October, indicates that the volume change associated with this inflation event has reached almost two times the volume change associated with the four previous inflation events in the same area between 2020-2022. Inflow of magma/magmatic fluids into the sill-type body is estimated at approximately 7 m3/s which is about four times greater than the highest inflow estimated during previous inflation events here.

While the inflation  continues, increased seismicity in the area can be expected from additional stress changes  induced within the crust. 

Data from GNSS station at Mt. Þorbjörn. The graph at the bottom shows the uplift.

 

Updated 4. November at 11:30pm

 

After 17:30 yesterday, seismic activity decreased considerably. In the last 12 hours, about 900 earthquakes have been detected, all under M3.0. The activity after midnight as mainly been located at Sundhnjúkagígar – NE of Þorbjörn, as well as west of Eldvörp.

Seismicity has decreased considerably since yesterday, but the development of earthquake magnitudes, number of earthquakes and their location is comparable to the development previously seen related to magma accumulation in the vicinity of Þorbjörn.

The latest deformation data shows that uplift continues in the area. This uplift is thought to be due to magma accumulation NW of Þorbjörn at 4-5 km depth. While that magma accumulation continues, increased seismicity in the area can be expected from increased stresses in the crust. Rockfall can occur following large earthquakes, so caution should be taken by steep slopes.

The Icelandic Meteorological Office continues to monitor the area closely and to meet with the Civil protection agency to discuss the situation. Signs of magma coming towards the surface would appear as increased, shallower seismicity and rapid crustal deformation at the surface as well as volcanic tremor, which is a high rate of many small earthquakes. At the moment no clear signs can be seen of any of this, but the situation can change on short notice.

Earthquakes (circles) with magnitude over 1.5, from midnight on 3 November until 10:45 on the 4 November. The colour bar to the left shows the time of the earthquakes and the size of the circles represents the relative size of the events. Locations of seismic stations (triangles) and GPS deformation stations (squares) are also shown.

 

Updated 3. November at 3pm

An earthquake of magnitude 4.3 was detected at 1:14 pm, today between Þorbjörn and Sýlingarfell. Another earthquake of magnitude 3.5 was detected at 2:01 pm in Þorbjörn. These earthquakes are thought to be due to continuing stress in the crust from magma accumulation undir Þorbjörn mountain. No volcanic tremor has been detected and the area is still being closely monitored.

Updated 3. November at 1:50pm

 

According to measurements from 11:00 am today, the uplift centered northwest of Þorbjörn continues. The uplift is caused by a magma intrusion at a depth of about 4 km. Seismic activity continues on the Reykjanes peninsula due to crustal stress changes caused by the intrusion. An increase in earthquake activity was detected after midnight and into the morning. Since midnight, around 1.000 earthquakes have been recorded in the area, with two being above M3.0 and two above M4.0. The biggest earthquake of the current swarm was measured at 8:06 am and was 4.3 in size. The biggest earthquakes last night seem to line up in a north-south direction west of Þorbjörn. This is happening on previously known fissures, where tension has been accumulating associated with plate tectonics and may curl due to tension from intrusions.

There are currently no clear signs of magma moving closer to the surface. Signs that magma is making its way to the surface would appear in shallower seismic activity and increasing tremor, which is a high frequency of small earthquakes. At the same time, sudden deformation of the surface should be measured with GPS measurements. The development of this event is closely monitored, as the course of events can change with very little notice.   

Model calculations show that the intrusion is located northwest of Þorbjörn, as shown in the accompanying image.  The most recent seismic activity has been over the intrusion itself. The earthquakes measured at Eldvörp and east of Grindavík road are due to tension from the magma intrusion by Þorbjörn, rather than signs of magma movements in those areas.

 

 

Approximate center of magma intrusion according to model calculations based on GPS and satellite images together with seismic activity from November 2nd at 8pm to November 3rd at 12pm larger that M1.0 in size. The model assumes a box-shaped intrusion, but its length and width are subject to quite a bit of uncertainty. The model will be frequently updated with the newest data once aquired, and the size and shape of the intrusion might change considerably, so there is quite some uncertainty to the model.

 

Updated 2. November at 3pm

 

GPS data from the last 24 hours indicate that uplift continues at a similar rate in the area northwest of Mt. Þorbjörn. Earthquake activity has been quite stable, but yesterday around 800 earthquakes were recorded in the area around Þorbjörn, and the largest was M3.7 at 12:56 am. Since midnight today, around 400 earthquakes have been recorded in the area, the largest measuring M2.8 at 9:51 am. More detailed analysis of recent GPS data confirms that a magma intrusion is forming at a depth of 4-5 km under the area northwest of Þorbjörn.  

It is important to note that seismic activity is will likely continue northwest of Þorbjörn, and earthquakes over M4.0 could be found in populated areas. Triggered seismic activity can also be expected in the coming days because the magma intrusion causes increased tension in the area. Rockfall can occur following strong earthquakes, so it is important to be cautious on steep slopes.  

 

Reviewed earthquakes from midnight November 1st until noon November 2nd.

Updated 1. November at 12:20pm

 

On 25 October, an intense earthquake swarm began near Svartsengi, north of Grindavík on the Reykjanes Peninsula. So far, over 10,500 earthquakes have been detected in the swarm, with over 26 earthquakes exceeding magnitude three, the largest of which was magnitude 4.5 on 25 October at 08:18 UTC.

The latest satellite radar image, acquired late on 31 October, reveals 5 to 6 cm of ground movements over 12 days, centered just northwest of Mt. Þorbjörn. The same displacement signal is seen in continuous GPS measurements from stations in the region, beginning on 27 October. The latest GPS results from 1 November indicate that ground displacements continue in the region. Combining seismic, geodetic, and satellite-based observations, we infer that a volcanic intrusion is located at about 4 km depth just northwest of Mt. Þorbjörn. Presently, there are no indications that the volcanic intrusion is becoming shallower. We expect that seismicity will continue northwest of Mt. Þorbjörn, and this could include felt earthquakes exceeding magnitude four. Triggered earthquake activity is also possible in the coming days due to stress increases caused by the intrusion. This is a likely explanation for the ongoing seismic activity detected west of Þorbjörn in Eldvörp on 1 November. Triggered seismicity is also possible due to the long-term effects of magma accumulation beneath Fagradalsfjall.

Satellitbaseret InSAR-billede af Reykjanes-halvøen, der strækker sig fra 19. til 31. oktober. Dette billede giver et indblik i jordens deformation i løbet af de sidste 12 dage. Det største deformationssignal er centreret nordvest for bjerget Þorbjörn. Fra GPS-målinger er det tydeligt, at størstedelen af ​​centimeterskalaen jordforskydning er sket siden 27. oktober.

 

Opdateret 31. oktober kl. 17.00

 

I morges kl. 8.40 begyndte en jordskælvsværm ved Þorbjörn, som varede i næsten 2 timer og var usædvanlig intens. Det største jordskælv i sværmen målte M3,7. Aktivitetens centrum var lige øst for midten af ​​den stigning, der er observeret de seneste dage. Jordskælvenes dybde blev anslået til mellem 5 og 1,5 km dybde. Jordskælvsværmen er et tydeligt tegn på magmabevægelser i dybden. GPS-målinger understøtter fortolkningen, selvom stigningen, der startede for omkring fire dage siden, er aftaget. Tidligere i dag var der et møde med civilforsvaret og interessenter på Reykjanes-halvøen, hvor de seneste målinger og mulige scenarier og svar på det aktuelle scenarie blev diskuteret.

Situationen overvåges nøje

IMO følger udviklingen nøje og ser på, om mikroseismisk aktivitet stiger tættere på overfladen, hvilket kan være et tegn på, at magma bryder sig vej gennem jordskorpen. I øjeblikket er der ingen tegn på, at jordskælvsaktiviteten bliver mere lavvandet. Situationen kan dog hurtigt ændre sig, og det er ikke muligt at udelukke et scenarie, der involverer et lavaproducerende udbrud i området nordvest for Þorbjörn. Det er vigtigt at påpege, at magmabevægelser, svarende til dem, der observeres tæt på Þorbjörn, ofte forsvinder og ikke fører til et vulkanudbrud. Ikke desto mindre kunne langvarig riftning og øget (udløst) jordskælvsaktivitet i Svartsengi-området have skabt svagheder i skorpen, hvilket gør det lettere for magma at bevæge sig til lavere dybder.

 

Gennemgået jordskælv fra midnat i dag.

Opdateret 30. oktober kl. 11.30

 

 

Sentinel-satellitdataene, der forventes at blive modtaget i går, er ikke ankommet endnu, men cGPS-dataene i området omkring Svartensgi og Þorbjörn viser, at deformationen stadig er i gang. Deformationshastigheden siden begyndelsen af ​​denne påtrængende begivenhed har været svagt faldende over tid. Foreløbige resultater fra deformationsmodeller tyder på, at den gennemsnitlige dybde, hvor den magmatiske instruktion finder sted, er omkring 4 km.

I løbet af de sidste 24 timer er omkring 1300 jordskælv automatisk blevet registreret på Reykjanes-halvøen. Det meste af denne seismicitet er placeret i en dybde mellem 2-4 km. Det største jordskælv havde en størrelsesorden M2,7 den 29. oktober kl. 11:40 UTC.

Forskere fra det islandske meteorologiske kontor foretager yderligere overflademålinger i området, herunder geokemiske observationer. Der opretholdes regelmæssig kommunikation mellem IMO, HS-Orka og Civilbeskyttelsen, mens denne uro fortsætter.

8-timers løsning til cGNSS THOB-stationen i Þorbjörn, der viser det seneste datapunkt opdateret kl. 08:00 UTC i dag

 

Opdateret 29. oktober kl. 14.00

 

De seneste cGPS-deformationsdata omkring Þorbjörn og Svartengi-området bekræfter, at deformationen, som startede 27. oktober, fortsætter. Som indledningsvis anført, er de igangværende deformationshastigheder højere end i tidligere hændelser, som fandt sted i et lignende område i 2020 og 2022. Samlet set har seismiciteten nord for Grindavík været faldende i løbet af det seneste døgn, og der er ingen væsentlige ændringer i jordskælvsdybderne. Det er dog vigtigt at understrege, at den nuværende deformation kan udløse fornyet seismicitet i området, som kunne mærkes af mennesker.

Nye satellitdata forventes at blive leveret senere i dag, og et nyt interferogram vil blive behandlet, så snart dataene er tilgængelige. Resultaterne vil give os mulighed for at identificere og fortolke de deformationsprocesser, der har fundet sted på halvøen i løbet af de seneste 12 dage. Vi forventede at offentliggøre resultaterne i morgen.

En episode med kompleks vulkan-tektonisk uro påvirker i øjeblikket Reykjanes-halvøen. Det fortolkes som et resultat af flere deformationskilder i dybden, som interagerer og påvirker et bredt område på tværs af halvøen.

8-timers løsning til cGNSS THOB-stationen i Þorbjörn, der viser det seneste datapunkt opdateret kl. 08:00 UTC i dag, den 29. oktober.

 

Opdateret 28. oktober kl. 13.30

 

De seneste cGPS-målinger, sammen med et nyligt erhvervet InSAR-billede over Reykjanes-halvøen, afslører et tydeligt tegn på jordløft, centreret omkring Svartsengi. Dette løftesignal begyndte på et tidspunkt den 27. oktober, og det afspejler en trykstigning, der sandsynligvis er forårsaget af en magmatisk indtrængen i dybden. Midten af ​​løftesignalet er omkring 1,5 km nordvest for Þorbjörn, tæt på Den Blå Lagune. I 2020 og 2022 blev lignende opløftningssignaler detekteret i samme område og med lignende geometri. Dette er nu den femte inflationsbegivenhed i området. Fra en indledende vurdering forekommer det igangværende opløftningssignal hurtigere end tidligere. I øjeblikket er der ingen indikationer på, at magma bevæger sig på lavere dybde. Situationen kan dog udvikle sig hurtigt. For eksempel er der sket betydelige fraktureringer i Svartsengi-området på grund af udløst seismicitet i de seneste dage. En sådan frakturering kunne gøre det muligt for magma at finde veje til mindre dybde.

Samlet set viser de seneste deformationsresultater fra Reykjanes-halvøen en kompleks, igangværende proces med magmabevægelser i jordskorpen. Disse processer påvirker et bredt område, herunder Fagradalsfjall (hvor langsigtet inflation fortsætter), øst for Festarfjall (hvor deformationen ser ud til at være stoppet), og – i de sidste 24 timer – viser et område tæt på Svartsengi inflation.

Den seismiske sværm, der begyndte den 25. oktober nord for Grindavík, har resulteret i over 7.000 jordskælv. Niveauet af jordskælv er reduceret betydeligt, selvom sværmen stadig er i gang, hvilket betyder, at der stadig er sandsynlighed for jordskælv.

Geophysical modelling is underway today to determine the depth and size of the uplift source close to Svartsengi. An additional satellite radar image will be available from Reykjanes Peninsula on 29 October. This image should provide an even closer insight into the recent magma movements and deformation pattens on the peninsula.

 

 

“Line-of-sight” (LOS) deformation measured by the ICEYE SAR satellite between the 26 October at 05:21 UTC and the 28 October at 05:21 UTC. Satellite data provided in collaboration with ICEYE (https://www.iceye.com/).

 

Updated 27th of October at 2pm

 

The ground-deformation signal detected since yesterday in the area East of Festarfjall is confirmed by the latest cGPS data. The horizontal displacement over the past few days is ~ 2 cm as seen at FEFC station and movement has now also been measured at another cGPS station located in Selatangar. A 1-day interferogram spanning 26 to  27 of October, does not reveal any significant changes in the area, but the signal at FEFC measured during this 24-hr period was smaller than 1 cm, likely too small to be detected by this interferogram.  cGPS stations in Grindavík and north of here show no significant changes.

The seismic swarm north of Grindavík continues with around 1000 earthquakes since midnight. A total of 5800 eqs have been recorded since the beginning of the activity. An earthquakes M4.0 was measured at 04:02 UTC on 27 October around 2 km north of Grindavík. The seismic activity is interpreted as the response of the crust to the stress changes induced by continued magmatic inflow at depth beneath the Fagradalsfjall volcanic system.

 

Displacement at cGNSS station FEFC east of Festarfjall. Blue vertical line marks the onset of a dike intrusion in July 2023 and the red line the start an eruption near Litli-Hrútur 10th of July 2023. Most recent data points show up movement and horizontal movement towards SE.

cGNSS stations at Reykjanes Peninsula. Data from stations FEFC and STAN east of Festarfjall show movement in the last day.

Updated: 26th of October at 5pm

 

The seismic swarm that commenced on 24 October continues. Over 4,000 earthquakes have been recorded on the Reykjanes Peninsula, of which 14 had a magnitude exceeding M3. Most of the activity has occurred between Stóra-Skogafell and North-East of Eldvörp. Seismicity is located between 2 and 6 km depth, with the largest earthquake (M4.5) measured on 25 October at 08:18 UTC. Scientists at the Icelandic Meteorological Office (IMO) interpret the ongoing seismic activity as triggered by stress induced by the ongoing deformation at Fagradalsfjall, which began soon after the summer 2023 eruption. The ongoing seismic swarm is expected to continue for the coming days. In the longer-term, the continued accumulation of magma beneath Fagradalsfjall could cause further seismic swarms on the peninsula.

Jorddeformationsmålinger nær Svartsengi og Grindavík viser ingen ændringer relateret til den igangværende seismiske sværm nord for Grindavík. En enkelt GPS-station (FEFC), øst for Festarfjall, begynder at vise lokaliseret bevægelse i sydøstlig retning. Disse målinger kunne indikere tilstedeværelsen af ​​magma i dybden langs fortsættelsen af ​​digeindtrængninger, der er i nordøstlige retning mod sydvest, som er dannet under Fagradalsfjall siden 2021.

Personale fra IMO fortsætter med at overvåge de seismiske uroligheder nøje. I de kommende dage vil satellitdata blive brugt til bedre at vurdere den rumlige udstrækning af enhver jorddeformation. Målingerne vil også blive brugt til bedre at forstå igangværende geofysiske processer på Reykjanes-halvøen.

 

Gennemgået udløste jordskælv fra 20.-26. oktober.

Skrevet 25. oktober: 

I nat startede en intens jordskælvsværm nær Svartsengi, nord for Grindavík. Over 1000 jordskælv er blevet opdaget der siden midnat, og sværmen er stadig i gang. De største jordskælv, der er registreret, er M3.9 kl. 5.35 UTC og M4.5 kl. 8.18 UTC. Begge disse jordskælv opstod på omkring 5 km dybde. Seneste deformationsdata indsamlet fra flere stationer omkring Þorbjörn/Grindavík området viser ikke signifikante ændringer korreleret med den igangværende seismiske aktivitet. I lyset af de data, der i øjeblikket er tilgængelige, fortolkes denne seismicitet til at være sandsynligt udløst af stressændringer relateret til tidligere påtrængende aktivitet på halvøen. Der er i øjeblikket ingen indikationer på magmavandring under Þorbjörn/Grindavík-området, men situationen kan ændre sig når som helst, og den kan udvikle sig over kort tid fra timer til dage. Som rapporteret i september er en magmatisk indtrængen i gang under Fagradalsfjall.

 

Personale fra IMO fortsætter med at overvåge området tæt og fortolke de nyeste data, efterhånden som de bliver tilgængelige.

Usikkerhedsniveauet for Department of Civil Protection er blevet erklæret på grund af denne seismiske sværm.

 

 

8-timers løsning til cGNSS THOB-stationen i Þorbjörn, der viser det seneste datapunkt opdateret kl. 08:00 UTC i dag.

Gennemgået jordskælvssteder fra midnat til middag den 25. ^oktober .

Automatiske lokaliseringer af jordskælv fra midnat til middag den 25. ^oktober .