Volcano and earthquake activity in Iceland
This morning around 06:30 a dyke intrusion started in Svartsengi volcano with a strong earthquake swarm. An eruption started at around 09:50 UTC. This eruption is happening only in the area south of the area that erupted on 21. November 2024. A dyke formed in this even and is around 11 km long. This dyke might get longer and is possibly getting longer at the writing of this article.
This situation is still developing and can change quickly. I’ll post update as needed if anything major happens.
During the last few weeks there has been slow increase in deep earthquakes in Eyjafjallajökull volcano. This is unusual because it erupted in the year 2010 and in general only erupts every 290 to 700 years, based on current data into the eruption history of Eyjafjallajökull volcano.
Depth of the earthquakes that have so far happened is around 24 to 26 km of those have been reviewed by Icelandic Met Office. Before the eruption in Eyjafjallajökull volcano in the year 2010 it took around 10 years from start of deep earthquakes until an eruption took place. This might just be deep earthquake activity that might not result in a eruption in next few decades. At the moment this earthquake activity is too small and too few earthquakes to know for sure what is going on.
Today (26-Mars 2025) at 15:06 UTC an earthquake with magnitude of Mw3,2 took place in Krýsuvík-Trölladyngja volcano, just east of Keilir mountain. There has not been a lot of aftershock activity following this earthquake.
This earthquake activity is possibly because of inflation in Svartsengi volcano. Since that results in stress changes along the Reykjanes peninsula, but mostly in the area closest to it. More earthquake activity can happen without warning in this part of Reykjanes peninsula.
Today (12-March 2025) at 14:29 UTC an earthquake swarm started in Reykjanes volcano. The largest earthquake had a magnitude of Mw3,8. At the writing of this article. This earthquake swarm seems to be ongoing.
This doesn’t look like an magma related earthquake swarm. This seems to be a fracture earthquake and might be connected to stress changes in the crust because of the high inflation in Svartsengi volcano, that is not far away from this location. The earthquake swarm is at a low now, but might increase again with stronger earthquakes without warning. If needed, I’ll post an update on what is happening.
This evening on 22-February 2025 at 21:04 UTC an earthquake with magnitude of Mw5,2 took place in Bárðarbunga volcano. This has been followed by several smaller earthquakes and this earthquake swarm seems to be ongoing.
This earthquake activity is possibly magma trying to find a path to the surface. If it is going to be successful now is another story. It is possible for the magma to fail this. It is difficult to know how this is going to evolve and progress in Bárðarbunga volcano. However, it is clear that for now, no eruption is imminent.
Today (24-January 2025) at 06:06 UTC an earthquake with the magnitude of Mw3,0 took place in Brennisteinsfjöll volcano. This doesn’t seem to have connected to magma movement in this area or volcano. This looks like more like a tension related earthquake. It was probably not related to inflation in Svartsengi volcano.
There is a risk of stronger earthquakes in this area. Currently there are no signs that this connected to magma movement in this area.
Today (18-January 2025) at 13:45 UTC an earthquake with magnitude of Mw3,2 took place in Krýsuvík volcano, this was just east of Keilir mountain. This earthquake was felt according to news reports. This resulted in a small earthquake swarm at this location.
This earthquake is not connected to magma movement in this area. This seems to be a tension release in the crust from the inflation of Svartsengi volcano. More earthquakes might happen in this area in next few days and until next eruption starts in Svartsengi volcano in Sundhnúkagígaröðin crater row.
Yesterday (16. January 2025) an earthquake swarm started in Ljósufjöll volcano. This is an area that has had an earthquake swarm since 2020 or 2021. Largest earthquake in this swarm had a magnitude of Mw3,2.
This earthquake swarm aligned it self with fault lines in the area. That is a change from earlier earthquake activity. Depth of the earthquake has also been decreasing. Its now around 14 km, from 17 to 23 km as it was before. Based on the earthquake activity, the amount of magma remains low and when the amount of magma is low. Its less likely to erupt. It rather is just stuck in the crust. However, if the amount of magma increases, that is going to increase the chance of an eruption in this area. This might take years, if not decades to happen as it stands now. Quick change seems unlikely at the writing of this article.
Today (14-January 2025) at 06:08 UTC an dyke intrusion started in Bárðarbunga volcano. This dyke intrusion lasted until around 09:00 UTC and might still not be over, even if the activity has stopped at the writing of this article. Largest earthquakes had the magnitude of Mw5,2 (USGS, EMSC). More than a dozen earthquakes with magnitude from Mw3,0 to Mw5,0 took place in this earthquake swarm.
The main activity was in the western part of the caldera. According to the experts, this earthquake swarm looks close to what happened in Bárðarbunga volcano before it erupted in Gjálp (Wikipedia, Icelandic) in the year 1996. Then a earthquake swarm started like this, slowed down for few days before it increased again and the eruption happened. It is unclear what direction the dyke might move to, but most likely is south-west in the direction of Torfajökull volcano and Katla volcano. If that happens, such dyke activity might get those volcanoes upset or start and eruption in them.
I am going to post update as needed for Bárðarbunga volcano as this activity continues.
On Sunday (29-December 2024) and yesterday (30-December 2024) an earthquake swarm took place in Reykjanes volcano, close to Eldey island. Largest earthquakes in this earthquake swarm had magnitude of Mw3,2 and Mw3,6. Over 200 earthquakes have been recorded at the writing of this article. This earthquake activity is possibly still ongoing. But this earthquake activity happens in waves with quiet time period between them.
It is unclear if this earthquake activity is because of tectonic movement or magma activity. I do suspect that this activity is because of magma movement in this area, based on earthquakes location, since it was focused on rather small locations. There are however no signs that this earthquake swarm is a start of an eruption at this location currently. There are limited GPS data on Reykjanes volcano, since part of it is under the ocean.