Earthquake activity in Askja volcano

Yesterday (14. March 2023) at 20:43 UTC an magnitude Mw3,0 earthquake took place in Askja volcano. This is just one of smaller earthquakes in Askja volcano. There have been almost no earthquake activity following the inflation in Askja volcano in recent months. Suggesting to me (this is my personal opinion) that this inflation is not going to result in a eruption. Deflation might start in few months or years time, if it starts at all. Why this happens the way it does is unknown to me.

Earthquake activity in the inner caldera of Askja volcano. Shown with blue, yellow and orange dots. There is some earthquake activity east of Askja volcano in Herðubreið mountain and nearby area.
Earthquake activity in Askja volcano. Copyright of this image belongs to Icelandic Met Office.

It is my personal view that earthquake activity in Askja volcano is going remain low and even vanish for a time. I don’t think anything is going to happen this time around. I am however known to get this wrong, because nobody can be sure what happens next in a volcano.

Earthquake activity in western part of Katla volcano

This morning (11. March 2023) at 07:02 UTC an earthquake with magnitude of Mw3,1 took place in western part of Katla volcano. This earthquake happened in Katla volcano caldera rim. The depth was 1,1 km. This was a single earthquake, at the writing of this article.

Green star in the western part of Katla volcano caldera. This is just a one star and one orange dot showing smaller earthquake slightly north of this earthquake.
Earthquake activity in Katla volcano. Copyright of this image belongs to Icelandic Met Office.

Since this earthquake there has not been any new earthquake activity in Katla volcano. I am not sure why that is, but it there’s a chance this earthquake activity might just be over. There has been a lot of frost quakes in last few hours, because of a cold weather happening in Iceland. With freezing going down to -20C in some areas.

Earthquake swarm in Katla volcano

Today (9. March 2023) an earthquake swarm started in Katla volcano. This earthquake swarm is ongoing and information in this article can go outdated quickly. Largest earthquakes at the writing of this article have a magnitude of Mw3,3 and Mw3,4. A swarm of smaller earthquakes is ongoing.

Two green stars in Katla volcano askja in Mýrdalsjökull glacier. Along with many red dots that show smaller earthquakes in Katla volcano.
Earthquake activity in Katla volcano. Copyright of this image belongs to Icelandic Met Office.

It is difficult to know for sure what is going on in Katla volcano. But this activity reminds me of what happened few years ago before an small eruption took place in Katla volcano. If that is going to happen now I don’t know. I’ll post information when I know more and if anything more happens in Katla volcano.

The earthquake activity in Skaftafellsfjöll mountain (part under Vatnajökull glacier)

Since May 2011 there has been an earthquake activity in mountain called Saftafellsfjöll. This is slightly north of Öræfajökull volcano and south of Grímsfjall volcano. This earthquake activity is now permanent in this area it seems. Some of it might be glacier quakes, but most of the earthquake activity there is not, because of the depth this earthquake activity is happening at.

Earthquake activity in Skaftafell in Skaftafellsfjöll mountain. Shown as blue, orange and yellow dots on the map of Vatnajökull glacier. Also on this map is earthquake activity in Askja volcano and Herðubreið shown with red dots.
Earthquake activity in Skaftafellsfjöll mountain. Copyright of this image belongs to Icelandic Met Office.
One year worth of earthquake data from Skjalftalísa program on Icelandic Met Office. It shows a clear concentration of earthquakes in Skaftafellsfjöll mountain over this time.
Earthquake activity in Skaftafellsfjöll mountain for 365 days. Picture is from Skjálftalísa on Icelandic Met Office website. Copyright of this image belongs to Icelandic Met Office.

I don’t know for sure what is going on. This earthquake activity clearly shows that something is going on in this part of Vatnajökull glacier. It is my unverified opinion that there is a volcano there. Its not documented and map only show a extinct volcano in this area. This is unlikely to be earthquake activity in extinct volcano, its not impossible, what makes this unlikely is that this earthquake activity happens regularly and has been going on since May 2011. There is ice quake activity in this same area, but some of this earthquake activity is both deep and being located in areas with no glacier. If those are not measuring errors or something like that (I find that unlikely in many cases). I don’t think there’s going to be an eruption in this area, at least not for a long time if it ever happens. This earthquake activity might have been going on for a lot longer then from May 2011.

– This is not an registered or confirmed volcano in this area. Unless there’s an eruption, it might be a long time until a confirmation happens.

Earthquake activity in Katla volcano

Yesterday (26. February 2023) and today (27. February 2023) there was an earthquake activity in Katla volcano. This is mostly normal activity in Katla volcano and no signs of an eruption or that an eruption is about to start. Largest earthquake in this swarm had a magnitude of Mw3,2. I don’t know if it was felt in nearby area.

Yellow dots and green star in Katla volcano caldera that is under Mýrdalsjökull glacier that is shown in white on this image, along with other nearby volcanoes. The askja of Katla volcano is shown as elongated circle.
Earthquake activity in Katla volcano. Copyright of this image belongs to Icelandic Met Office.

There is no change in harmonic tremors or other activity in Katla volcano. That means this is just an earthquake activity and there is no sign that an eruption is about to happen.

Earthquake swarm close to Geirfugladrangur on Reykjanes ridge

Today (21. February 2023) an earthquake swarm started close to Geirfugladrangur on Reykjanes ridge. This is possibly in another volcano than Reykjanes volcano that is just east of this location, this is because of distance and its unlikely that Reykjanes volcano extends this far south. It has no other name than Geirfugladrangur. Largest earthquake in this swarm had a magnitude of Mw3,1 and this earthquake swarm is ongoing and stronger earthquakes are a possibility.

Earthquake swarm on the Reykjanes ridge, marked by orange and green star were the largest earthquake took place. A lot of yellow dots close to Reykjanestá area.
Earthquake swarm on Reykjanes ridge. Copyright of this image belongs to Icelandic Met Office.

This earthquake pattern seems to indicate that a magma dyke intrusion is taking place. This area of the Reykjanes ridge last erupted in 16th to 18th century and has been quiet since.

Light sized earthquake in Bárðarbunga volcano

Today (21. February 2023) at 08:41 UTC an earthquake with magnitude of Mw4,9 took place in Bárðarbunga volcano. This is because of inflation that is now happening in Bárðarbunga volcano and has been going on since end of Holuhraun eruption in 2015. Earthquakes with this type of magnitude are going to happen once or twice a year until Bárðarbunga volcano is ready for next eruption and that can take decades. There are going to be smaller earthquakes between larger earthquakes. According to the news, this earthquake was felt in Akureyri.

Green star and red dots in Bárðarbunga volcano inside Vatnajökull glacier. Few dots in other volcanoes in this part of Iceland.
Earthquake activity in Bárðarbunga volcano. Copyright of this image belongs to Icelandic Met Office.

Last time this happened it took 112 years between eruptions in Bárðarbunga volcano. With the quiet period between 1902 and until 2014. Shortest time between eruptions seems to be around 40 years, but most eruptions happen between 90 to 112 years from last eruption. Based on the data from Global Volcanism Program on Bárðarbunga volcano. There is a lot of uncertainty in this data, so this might be shorter from what it looks like in the data.

I’ve switched to using standard definition for earthquake magnitudes, as shown here (Wikipedia). This is for clarification and simplification when I am writing about earthquakes.

Strong earthquake swarm in Reykjanes volcano on Reykjanes ridge / Reykjanes peninsula

This earthquake swarm is ongoing at the writing of this article and information can change without warning. The largest earthquake recorded by automatic magnitude of Mw3,7 at the writing of this article. Around 30 to 40 earthquakes have happened so far, but that number might change quickly. This earthquake activity has some signs that it might be happening because of magma intrusion in the area, out in the ocean but signals are not clear.

Three green stars and red dots on the left down side on the map of Reykjanes peninsula, the earthquake activity is happening out in the ocean on the Reykjanes ridge.
The current earthquake activity on Reykjanes ridge. Copyright of this image belongs to Icelandic Met Office.

This earthquake activity is in the volcano Reykjanes, that volcano goes into the ocean and is on dry land. Making possible future eruptions both explosive and flowing magma at the same time. To date, Reykjanes volcano only has had earthquake swarms and no eruption. When that is going to change is impossible to know.

Small earthquake swarm in Bárðarbunga volcano

Today (7. February 2023) an small earthquake swarm took place. This earthquake swarm started at 11:21 UTC with a magnitude Mw3,2 earthquake and lasted until 12:05 UTC. Other earthquakes were smaller in magnitude.

Green star in the west side of Vatnajökull glacier, were the largest earthquake took place in Bárðarbunga volcano. Few other red dots at the same location show the smaller earthquakes.
Earthquake activity in Bárðarbunga volcano. Copyright of this image belongs to Icelandic Met Office.

This shows that Bárðarbunga volcano continues to inflate at high rate. Based on what happened before the eruption in 2014 to 2015 in Bárðarbunga volcano. When the earthquake stop for long time period it means Bárðarbunga volcano is ready for an eruption. While the earthquake activity happens is it is doing today, it means inflation continues in Bárðarbunga volcano.