Deformation measurements point out that uplift could have resumed | Information

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4.4.2025

Up to date April 4, at 14:55 UTC

• Indications that uplift has resumed in
  Svartsengi
• Seismic exercise close to the dike has
  decreased
• Deformation measurements nonetheless present
  motion at GPS stations across the northern a part of the dike
• Uncertainty stays in regards to the coming
  days, and magma actions throughout the dike can’t but be dominated out
• Triggered seismic exercise at
  Trölladyngja final evening, the most important measuring 3.9 in magnitude
• The hazard evaluation has been up to date
  and is legitimate till April 8 except circumstances change

GPS measurements point out that uplift could have
resumed in Svartsengi, as proven within the accompanying determine. The almost definitely
trigger is sustained magma accumulation beneath Svartsengi, although a part of the
uplift could also be attributed to the results of the dike formation on April 1. This
is as a result of when dikes kind, they push the crust away on both aspect. At this
stage, it’s troublesome to find out the speed of magma accumulation, and it could
take as much as per week to evaluate the way it evolves beneath Svartsengi.

Deformation knowledge additionally exhibits that motion
continues at GPS stations across the northern a part of the dike, together with in
Vogar and close to Keilir. Satellite tv for pc photographs exhibiting adjustments between April 2 and three
at 16:00 affirm this motion. The identical knowledge additionally reveals measurable fault
displacements of some millimetres within the jap a part of Grindavík.

The graphs present 8-hour options for GPS stations SENG (positioned in Svartsengi)
and VOGC (in Vogar). The info presents displacements within the north, east, and
vertical instructions (prime, center, backside). The vertical movement at SENG exhibits
indicators that uplift has resumed after appreciable subsidence when magma entered
the dike on April 1. Knowledge from VOGC nonetheless displays actions associated to the
northern a part of the dike, though the station is positioned almost 7 km from it.

Lowering seismicity however
deformation and microseismic exercise persist

Seismic exercise over the northern a part of the
dike continues to lower, although small earthquakes are nonetheless being recorded
within the space. In the course of the previous evening and this morning, about 20 to 30 earthquakes
have been measured per hour, most beneath magnitude 1.0. At peak exercise, over 100 earthquakes
have been detected per hour. Most earthquakes are unfold from Stóra-Skógfell within the
south to simply north of Keilir. Their depths are principally between 4 and 6 km,
which has remained steady in latest days.

The overwhelming majority of magma that left
Svartsengi is now throughout the dike shaped on April 1, in some locations at depths
of round 1.5 km, in accordance with modeling knowledge. Deformation because of the dike and
microseismic exercise in its northern half stay unusually excessive, though
it’s lowering. As a result of this, there may be nonetheless appreciable uncertainty about
developments within the coming days, and magma actions throughout the dike can’t be
dominated out.

The map exhibits the placement of all reviewed earthquakes on the Reykjanes
Peninsula over the previous 24 hours. It additionally exhibits preliminary estimates of the
dike’s location, extending from Grindavík within the south to an space about 3 km
northwest of Keilir. The blue bars present the variety of earthquakes—each reviewed
and unreviewed—per hour for the reason that morning of April 1. The whole variety of earthquakes
has declined over the previous day. The underside graph exhibits the magnitudes of the
earthquakes, which have continued to lower. Darker circles point out reviewed
occasions; lighter ones are unreviewed.

Swarm close to Trölladyngja
probably triggered by stress adjustments

At 17:30 on April 3, a notable earthquake
swarm started close to Trölladyngja, northwest of Kleifarvatn. The most important eartquake
within the sequence occurred round 23:00 and measured M3.9. Because the swarm started,
six earthquakes above magnitude 3 have been recorded. Many studies have been
obtained that the occasions have been felt in populated areas. After midnight, exercise
within the space started to say no. The earthquakes close to Trölladyngja are probably
triggered earthquakes on account of stress adjustments following the dike intrusion on April
1. There stays a chance of similar-sized triggered occasions in close by
areas like Trölladyngja and Reykjanestá within the coming days and weeks. Setja hyperlink hér

Hazard evaluation
unchanged

The Icelandic Meteorological Workplace has
up to date the hazard evaluation, and the general hazard stage for all zones
stays unchanged from the earlier model. The evaluation is legitimate, except
in any other case famous, till 15:00 on April 8.

Knowledge collected by consultants from the Icelandic
Institute of Pure Historical past throughout an aerial survey of the eruption website in
the afternoon of April 1 has been processed. The ensuing map exhibits that the
lava subject shaped in the course of the 6-hour eruption lined about 0.23 km² and had an
common thickness of roughly 1.7 m.

Up to date April 3, at 15:25 UTC

• The occasion will not be over, as plenty of
  small earthquakes are nonetheless being measured alongside the northern a part of the
  magma intrusion.
• The probability of a brand new vent opening in
  the northeastern a part of the intrusion decreases with time.
• Important uncertainty stays concerning
  the continuation of this occasion, as a excessive variety of small earthquakes are
  nonetheless detected on the northern finish of the dike.
• Magma stream from beneath Svartsengi into
  the Sundhnúkur crater row has stopped.
• Deformation measurements over the approaching
  days and weeks will shed a light-weight on how magma accumulation beneath
  Svartsengi is evolving.
• Deformation knowledge point out that the
  northernmost a part of the dike has reached a area just below 4 km north
  of Keilir.

Evaluation of webcam footage, drone movies, and
gasoline measurements present that the eruption, which started at 9:44 AM on April 1st,
ended round 4:45 PM the identical day. The eruption lasted simply over 6 hours,
making it the shortest eruption within the present eruption cycle on the Sundhnúkur
crater row.

Nevertheless, the occasion will not be but over, as small
earthquakes proceed to be measured alongside the dike, notably north of
Stóra-Skógfell, though seismic exercise has decreased over the previous 12 hours.
Little earthquake exercise is recorded within the southern a part of the dike.

Seismic exercise has additionally decreased in areas
reminiscent of Reykjanestá, Eldey, and Trölladyngja, the place triggered seismicity has
occurred in latest days.

The map exhibits the placement
of all reviewed earthquakes on the Reykjanes Peninsula in the course of the previous 24 Hours.
The blue bars point out the variety of earthquakes per hour for the reason that morning of
April 1. The chart exhibits that the variety of earthquakes stays appreciable.
Nevertheless, the graph beneath, which shows the magnitudes of the earthquakes,
signifies that their measurement has typically decreased over the previous 24 hours.

Unlikely {that a} new vent will kind

Subsidence will not be measured in Svartsengi
anymore, which signifies that magma stream from Svartsengi into the dike has
decreased to such a level that floor deformation is not detected by
GPS stations.

It turns into more and more unlikely {that a} new
vent will kind within the northeastern a part of the dike, though uncertainty
stays so long as earthquake exercise persists within the space. This evaluation is
primarily based on the dearth of continued subsidence in Svartsengi, implying that magma
inflow into the dike has grow to be minimal. Moreover, a lot of the magma has
already moved from Svartsengi into the dike, making it unlikely that ample
strain stays to power magma to the floor.

Deformation measurements within the coming days
and weeks will make clear how magma accumulation beneath Svartsengi develops.

The hazard evaluation issued on April 2nd
stays in impact till 3:00 PM on April 4th, except circumstances change.

New graben shaped on the northern
finish of the brand new dike

Deformation measurements present that the
northernmost a part of the dike lies in an space just below 4 km north of Keilir.
Satellite tv for pc imagery and modeling point out that the magma intrusion got here closest
to the floor about 5 km northeast of Stóra-Skógfell, the place its uppermost
part lies at a depth of round 1.5 km.

Satellite tv for pc photographs additionally present fault actions
above the northern part of the dike, within the space northeast of
Litla-Skógfell, the place a brand new graben (subsidence valley) has shaped.

Fault actions have additionally been noticed inside
the city of Grindavík, though to a lesser extent than these seen in the course of the
January 2024 eruption. Moreover, faulting was recorded at Reykjanestá
following a magnitude 5.3 earthquake that occurred within the afternoon of April
1st.

The interferogram illustrates floor
deformation that occurred between March 31 and April 2. The white fault line
marks the estimated location of the magma intrusion that shaped on April 1.
Extra white traces point out the place floor fault actions have been detected. The best deformation has been measured in
areas the place the coloured fringes are most tightly spaced. This contains the
Svartsengi space, the place the land subsided by roughly 25 cm, and on each
sides of the northern a part of the dike. The grey overlay exhibits the extent of lava
flows shaped for the reason that starting of the eruption episode in December 2023,
whereas the orange overlay exhibits the lava subject produced by the April 1 eruption.

Up to date April 2, at 15:15 UTC

• No eruptive exercise has been noticed at
  the fissure since yesterday afternoon, though glowing continues to be seen
  within the new lava subject.
• The dike that shaped yesterday is sort of
  20 km lengthy and is the longest one noticed for the reason that seismic unrest started
  in November 2023.
• Since yesterday morning, the bottom has
  subsided greater than 25 cm on the GPS station in Svartsengi (SENG) and
  continues to subside, though at a a lot slower price.
• Roughly 90% of the magma that had
  collected within the magma chamber beneath Svartsengi for the reason that finish of the
  earlier eruption in December 2024 has already transferred into the dike
  that shaped on April 1.
• Over time, the probability of a brand new
  eruptive opening forming alongside the dike is lowering, although it can’t be
  dominated out on account of ongoing microseismicity within the space.
• Displacements have been recorded on a number of
  GPS stations inside Grindavík in reference to fault actions.

No exercise has been noticed on the eruptive
fissure since yesterday afternoon, although glowing continues to be seen within the newly
shaped lava. The world stays unstable and dangerous. Measurements present that
the lava quantity erupted yesterday was about 0.4 million cubic meters. This
estimate relies on knowledge collected by consultants from the Icelandic Institute of
Pure Historical past throughout an aerial survey of the eruption website yesterday
afternoon. The lava subject shaped is the smallest one noticed for the reason that
eruption sequence at Sundhnúkur crater row started in December 2023. Its quantity
is roughly 1/6 of the lava subject from the January 2024 eruption, which
was the second smallest occasion within the sequence.

 The map exhibits the extent of the lava subject shaped throughout
yesterday’s eruption, primarily based on measurements by the Icelandic Institute of
Pure Historical past.

Regardless of the small lava subject, the dike that
shaped yesterday is sort of 20 km lengthy—the longest for the reason that onset of seismic
unrest in November 2023. This implies that the overwhelming majority of magma that
left the magma chamber beneath Svartsengi, about 90% of the quantity collected
for the reason that earlier eruption in December 2024, was utilized in forming the dike, and
solely a small portion reached the floor north of Grindavík.

Since yesterday morning, floor subsidence of
greater than 25 cm has been recorded on the GPS station in Svartsengi (SENG). The
newest GPS measurements, from 8 a.m. this morning, affirm that subsidence is
ongoing, although it has slowed considerably. Many of the magma that had
collected for the reason that final eruption has now moved from Svartsengi into the
newly shaped dike.

The graph exhibits 4-hour options for the GPS station SENG, positioned
in Svartsengi. The info shows displacements within the north, east, and vertical
instructions (prime, center, backside).

In reference to faulting inside Grindavík,
displacements have been measured at a number of GPS stations within the city. The most important
displacements occurred within the jap a part of the city. For example, vertical
motion of simply over 10 cm and horizontal displacement of 5–8 cm was recorded
at a station on Austurvegur. Within the western half, horizontal motion of about
6 cm was measured on the station on the western fringe of city. The whole
displacement noticed inside Grindavík for the reason that onset of the occasion yesterday
morning is as much as about 50 cm, distributed over a number of faults within the space.

Seismicity and deformation have
decreased since final evening

Because the magma intrusion started round 06:30
yesterday morning, roughly 2,400 earthquakes have been detected in
reference to the dike formation. The dike propagated steadily northeast
till about 21:00 final evening. Since then, exercise has remained centered north
of Fagradalsfjall and lengthening previous Keilir. Seismic exercise continues at a
reasonable stage, however earthquake magnitudes have typically decreased in comparison with
yesterday, as illustrated within the accompanying determine. Deformation measurements
additionally point out that the dike extends past Keilir, aligning with the
distribution of seismicity.

Seismic exercise above the dike from 06:30 on April 1 to 12:00 on
April 2. High proper: earthquake magnitude. Center graph: variety of earthquakes
per hour. Decrease left: earthquake latitudes. Decrease proper: earthquake longitudes.

Probability of recent eruptive opening
lowering over time

Given the present growth within the southern
a part of the dike—marked by the absence of eruptive exercise and low
seismicity—it’s more and more unlikely that the eruption which started yesterday
will reinitiate. Concerning the northeastern a part of the dike, the probability of
a brand new eruptive opening can also be thought of decrease with time, though it can’t
be dominated out on account of persistent microseismicity within the space.

Deformation measurements over the approaching days
will present a clearer image of whether or not magma continues to stream from
Svartsengi into the dike and the way magma accumulation beneath Svartsengi evolves.

The hazard evaluation has been up to date and is
legitimate till 15:00 on Friday, April 4, if no adjustments happen. Key updates embody:

• Zone 3 (Sundhnúkur crater row): Total hazard
  stage now assessed as excessive (pink), down from very excessive (purple).

• Zone 4 (Grindavík): Hazard stage decreased
  to appreciable (orange), from excessive (pink), because the probability of a brand new
  eruptive opening has decreased.
• Zone 6: Hazard stage now thought of
  appreciable (orange), beforehand excessive (pink).

Geological inspection and monitoring of faults
inside Grindavík doesn’t fall beneath the jurisdiction of the Icelandic
Meteorological Workplace. Nevertheless, GPS knowledge from the IMO point out fault actions
inside Grindavík associated to the dike intrusion that shaped on April 1.

The hazard map issued by the Icelandic Meteorological Workplace doesn’t take into
account the private threat related to coming into the marked zones. The IMO
refers as an alternative to the chance evaluation ready by the Authorities Job Drive on
Grindavík and the suggestions of the Police Commissioner of Suðurnes.

 

Up to date April 1st at 21:40 UTC

Primarily based on webcam observations, no eruptive
exercise is seen on the fissure that opened this morning simply north of
Grindavík. Solely minor glow is detectable right here and there alongside the eruption
fissure and throughout the lava subject.

Seismic exercise and deformation on account of magma
motion proceed on the northeastern finish of the dike that shaped at present. In
whole, seismic exercise has been recorded throughout a roughly 20 km lengthy space,
extending from the southern finish of the eruptive fissure to the placement the place
seismicity is now most intense.

The earthquakes are nonetheless occurring at
appreciable depth, and there aren’t any indicators that the migrating magma is
approaching the floor. Based on mannequin calculations from this afternoon,
roughly 15 million cubic meters of magma had flowed from Svartsengi into
the dike beneath the Sundhnúkur crater row, with solely a small fraction of that
quantity having reached the floor. Previous to the eruption, round 22 million
cubic meters of magma had collected within the magma reservoir beneath Svartsengi
for the reason that final eruption, suggesting that there should be potential for
additional magma motion.

So long as seismic exercise and deformation
proceed throughout the dike, the potential of a brand new eruptive fissure opening
should be thought of. The almost definitely location for such a gap is within the space
the place seismic exercise is at present most intense. Ought to an eruption happen, it
could also be accompanied by vital seismic exercise, probably noticeable to
residents in Vogar.

Map exhibiting reviewed earthquakes on the
Reykjanes Peninsula since 6 AM, April 1st.

Up to date April 1st at 18:30 PM

Volcanic exercise north of Grindavík continues
to lower, with little seen exercise on webcams or in latest drone
footage. Nevertheless, seismic exercise continues. Earthquake exercise close to the
southern a part of the magma dike, near Grindavík, has decreased, whereas
exercise on the northern finish of the dike continues with comparable depth and
has shifted even additional north in latest hours. The seismic exercise now
extends nearly 9 km farther north than the northernmost eruption fissure shaped
in the course of the August 2024 eruption. The most important earthquakes have been round
magnitude 3 and have been felt in Vogar, which is about 7 km northwest of the
energetic space.

The map exhibits the placement of earthquakes recorded at present, April
1, 2025, together with recognized fault traces within the space. It signifies that the
dominant fracture orientation within the area is NE-SW. No recognized fractures are
mapped within the Vogar space.

Deformation measurements present that magma is
nonetheless flowing from Svartsengi into the dike beneath the Sundhnúkur crater row.
The seismic exercise means that the magma is transferring northeast. Earthquakes
are occurring at depths of roughly 4–6 km, and deformation knowledge from this
space is at present being analyzed. So long as vital seismic exercise and
deformation proceed, there stays a chance that magma might attain the
floor once more within the Sundhnúkur crater row or close by the place exercise is most concentrated.

The next map exhibits
the lava extent as of 12:34 PM, shaped by the eruption that started this
morning. The map relies on ICEYE satellite tv for pc imagery.

The hazard evaluation has
been up to date and is legitimate till 3:00 PM tomorrow, April 2,
except circumstances change. The hazard stage for Zone 3 (Sundhnúkur crater row)
stays very excessive (purple). In Zone 4 (Grindavík), the hazard stage has been
downgraded to excessive (pink), on account of decreased threat from ashfall and gasoline air pollution.
Adjustments have additionally been made to the hazard ranges in Zones 7 and 5, which have
been raised from reasonable (yellow) to appreciable (orange) on account of ongoing
seismic exercise close to the northeastern finish of the dike.

Up to date April 1st at 14:40 PM

Based on webcam observations, the volcanic
exercise seems to have decreased considerably previously hour. 

Seismic exercise continues to be ongoing however is
principally positioned on the northern and southern a part of the dike intrusion.

Deformation measurements
nonetheless present continued motion to the northeast, indicating that magma continues to be
flowing into the dyke

Up to date April 1st at 12:35 PM

The whole size of the eruptive fissure is
now about 1,200 meters and continues to increase southward.

The Icelandic Meteorological Workplace obtained a report {that a} scorching water pipeline
has damaged within the northern a part of Grindavík. This confirms that vital
fault actions have occurred throughout the city.

Ongoing seismic exercise is being recorded
alongside the complete dike intrusion, with probably the most intense exercise on the
northeastern finish. The intrusion now extends over 3 km additional to the northeast
than noticed in earlier eruptions. Deformation knowledge additionally present continued
displacement towards the northeast. This means that magma continues to be transferring
by the dike intrusion.

Seismic exercise over the dike intrusion since 4 AM this morning, April 1st.

Up to date April 1st at 11:00 AM

The fissure has prolonged southward. A brand new
eruptive fissure has opened a couple of hundred meters contained in the protecting boundaries
north of Grindavík – between the boundaries and the city itself.

(The brand new fissure opening is on the left on the photograph).

The climate forecast signifies southwesterly
winds at present (Tuesday), carrying volcanic gasoline northeastward, together with over the
capital space. Winds are anticipated to calm within the night, concentrating the gasoline
air pollution primarily across the eruptive fissure. Tomorrow morning (Wednesday),
winds will shift to northwesterly and later westerly, dispersing the gasoline
southeastward and later eastward – together with over Þorlákshöfn and the Ölfus
area. The gasoline dispersion forecast might be discovered right here.

Seismic exercise continues on the southern finish
of the magma intrusion and likewise north of Stóra-Skógfell. Earthquakes have additionally
been measured close to Reykjanestá, that are probably triggered (fault-slip)
earthquakes on account of stress launch associated to the exercise within the Sundhnúkur
crater row. Extra details about the exercise might be discovered right here .

Up to date April 1st at 10:30 AM

Preliminary studies from the Coast Guard
surveillance flight point out that the fissure is now about 700 meters lengthy and
has remained comparatively steady, though it can’t be dominated out that it could
prolong additional north or south. Seismic exercise and deformation measurements
proceed to point out ongoing exercise.

The hazard evaluation has been up to date. The
alert stage for the Sundhnúkur crater row (Zone 3) has been raised to very
excessive hazard (purple), and in Grindavík (Zone 4) has been elevated from excessive
hazard (pink) to very excessive hazard (purple). This hazard evaluation is legitimate till April 2 at 10:30 AM, except circumstances
change.

Up to date April 1st at 10:00 AM

The fissure is now about 500 meters lengthy and
has reached by the protecting barrier north of Grindavík. The fissure
continues to develop, and it can’t be dominated out that it could proceed to open
additional south.

Updates from the Coast Guard helicopter are nonetheless awaited.

The map exhibits the fissure that’s now about 500 m. lengthy.

Up to date April 1st at 9:45 AM

An eruption has began simply north of the
protecting barrier close to Grindavík.

A Coast Guard helicopter will take off shortly
to verify the precise location and measurement of the eruption.

The size of the magma intrusion beneath the
Sundhnúkur crater row that has already shaped is about 11 km, which is the
longest measured since November 11, 2023.

Extra data can be accessible quickly.

Given the present wind course, gasoline
air pollution from the eruption can be carried northeast towards the capital space.
It isn’t doable to foretell the depth of the air pollution.

Here’s a hyperlink to the Icelandic Met Workplace’s
gasoline dispersion forecast.

Up to date April 1st at 9:20 AM

The hazard evaluation has been up to date on account of a magma intrusion within the Sundhnúkur crater row. On account of the intrusion, the probability of a volcanic eruption has elevated.

The hazard stage in space 3 has been raised from “excessive hazard” to “very excessive hazard” (purple), and in space 4 (Grindavík), the hazard stage has been raised from “appreciable hazard” (orange) to “excessive hazard” (pink).

The up to date hazard evaluation is legitimate till 9:00 AM on April 2, supplied that circumstances don’t change.

Up to date April 1st at 8:20 AM

Indicators from GPS meters are stronger than
these noticed throughout latest occasions within the Sundhnúkur crater row. This
signifies {that a} appreciable quantity of magma is at present on the transfer.

The indicators present that magma is transferring each to the
northeast and southward towards Grindavík. At this stage, it isn’t doable to
decide the place the magma will emerge, nevertheless it’s noteworthy that the southern displacement
of deformation indicators was not noticed in the course of the eruption that started in
November 2024.

Emergency responders in Grindavík have reported
that earthquakes might be felt within the city, and indicators of deformation are additionally
seen there, suggesting that fault actions might happen throughout the city
itself.

Up to date on April 1st at 7.25 AM

An earthquake swarm started at round 6:30 AM this
morning on the Sundhnúks Crater Row. The swarm is positioned between Sýlingarfell
and Stóra-Skógfell, in an identical are as seen previous to earlier eruptions.

The earthquake swarm was adopted by a transparent change in
deformation and strain adjustments in boreholes operated by HS Orka. Each
impartial measurements have been a transparent signal of the onset of a magma
intrusion. 

No magma has reached the floor as of now, however an
eruption is more likely to happen.

The brand new can be up to date.