Author: Jón Frímann

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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.

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Earthquake swarm north of Herðubreið mountain

Today (17. February 2023) at 09:26 UTC an earthquake with magnitude of Mw3,5 took place around 4 km north of Herðubreið mountain. This earthquake seems to have started an earthquake swarm in that area. It is unclear if this earthquake activity is connected to inflation that is taking place in Askja volcano.

Green star north of Herðubreið mountain. This is east of Askja volcano. Few dots of smaller earthquakes also in Askja volcano.
Earthquake activity in Herðubreið mountain. Copyright of this image belongs to Icelandic Met Office.

There has been increase in earthquake activity at this location in Herðubreið mountain, but why is unclear.

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Strong earthquake swarm north of Kolbeinsey island [Updated]

Today (14. February 2023) at 01:24 UTC an earthquake swarm started around 70 to 90 km north of Kolbeinsey island. It might be in Kolbeinsey island. Largest earthquakes recorded at the writing of this article had a magnitude of Mw3,5 according to Icelandic Met Office. EMSC is reporting two earthquakes with magnitude of mb4,5 at the writing of this article.

Two green stars far north of Iceland in the ocean. Showing the location of the earthquakes north of Kolbeinsey island. This is all view map of Iceland and shows all the other earthquakes that have taken place in Iceland for the last 48 hours.
Earthquake activity north of Kolbeinsey island. Copyright of this image belongs to Icelandic Met Office.

Distance from land makes it difficult for the SIL network that Icelandic Met Office runs to detect the smallest earthquakes. This means there can be a lot more going on that appears on earthquake maps. There’s always a chance of stronger earthquakes in this area north of Iceland.

Update
Update at 16:50 UTC on 14. February 2023

Icelandic Met Office has finished reviewing the earthquake activity north of Kolbeinsey and around eight earthquakes with magnitude above Mw3,0 took place. Largest earthquake had a magnitude of mb4,6 according to EMSC. Information about that earthquake can be found here.

Ten green stars far north of Iceland showing the earthquake activity north of Kolbeinsey island. Other earthquakes that also happen in Iceland are visible on this map.
Earthquake activity far north of Iceland. Copyright of this image belongs to Icelandic Met Office.

This earthquake activity appears to be over, but distance from seismic detection networks in Iceland prevents detection of smaller earthquakes that might be happening at this location.

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Eruption expected in Fagradalsfjall volcano this year (2023) or next year (2024)

It was reported in Rúv News that eruption is expected to happen in Fagradalsfjall volcano this year (2023) or next year (2024). When those eruptions happen is impossible to know. But before any eruption there’s going to be a large earthquake swarm as happened before the eruption in March 2021 and in August 2022. Fagradalsfjall volcano before the eruption in March 2021 had not erupted for 6000 to 8000 years. That means it unclear how the volcano is going to behave and its going to take a while until that is figured out, but for now it is probable that Fagradalsfjall volcano is going to work in similar way how Krafla volcano erupted between the year 1975 and 1984. With the difference that eruptions in Fagradalsfjall volcano are possibly going to last longer, based on data from other volcanoes on Reykjanes peninsula. This might go on for the next 10 to 20 years, with eruptions and quiet time period between them. Currently Fagradalsfjall volcano is in a quiet time.

This does not rule out eruptions in Reykjanes volcano (west of Fagradalsfjall volcano) and Krýsuvík-Trölladyngja volcano (east of Fagradalsfjall volcano) in next few years. Neither of those volcanoes have erupted in 700 to 900 years and at the writing of this article, don’t show any clear signs that they are about to erupt. Reykjanes volcano has had a lot of dyke intrusion activity since 2019, but no eruptions so far. Krýsuvík-Trölladyngja volcano has not had any dyke intrusion activity. Volcanoes east of Krýsuvík-Trölladyngja volcano, Brennisteinsfjöll volcano and Hengill volcano are currently quiet, but that might change without warning if magma starts to find path up those volcanoes.

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Earthquake south of Kolbeinsey island

Yesterday (10. February 2023) at 16:25 UTC an earthquake with magnitude of Mw3,1 took place around 41 km south of Kolbeinsey island.

Green star and yellow dots at the location of the earthquakes south of Kolbeinsey island.
The earthquake south of Kolbeinsey island. Copyright of this image belongs to Icelandic Met Office.

This earthquake was far from any populated areas of Iceland and was not felt for this reason.

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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.

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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.

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Earthquake with magnitude of Mw7,5 in South Turkey

Today (06. February 2023) at 10:24 UTC an earthquake with magnitude of Mw7,5 took place. This earthquake took place less than 12 hours after the Mw7,8 earthquake took place 50 km south of this earthquake. USGS is reporting (seen on CNN) that 10000 people might have died in this earthquakes because of were it is located. The real number might be higher. News is also reporting that 582 people have died in Syria because of this earthquakes. There is heavy aftershock activity in this area and the second largest aftershock had a magnitude of Mw6,7 at 01:28 UTC.

Earthquakes as shown by USGS map. Large orange dots showing the earthquake activity in different sized rings. Size of rings depends on magnitude. More then dozen rings.
Earthquake activity as it is on USGS map. Public domain/USGS.

Information about the Mw7,5 earthquake can be found here at EMSC and here at USGS. Information about the Mw6,7 earthquake can be found here at EMSC website.

Update (22:38 UTC)

The magnitude Mw7,5 earthquake has been confirmed to be an aftershock by USGS.

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Earthquake with magnitude of Mw7,8 in Turkey

Today (6. February 2023) at 01:17 UTC an earthquake with magnitude of Mw7,8 took place in south Turkey. Damage is to be expected in this type of earthquake. This earthquake was felt over a wide area. Because of high electric price, I’ve been unable to run my seismometer in Denmark and I did not record this earthquake for that reason. At this magnitude this earthquake was recorded all over Europe in professional and citizen science seismometers.

EMSC information can be found here and USGS information can be found here. Links can stop working without warning.

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Increase in larger earthquakes in Katla volcano (there’s no risk of eruption)

This might not be anything at the writing of this article. Since there’s little earthquake activity in Katla volcano at the moment, its well below background noise. Over the last several months I’ve noticed an slight increase in larger earthquakes in Katla volcano, this might not mean anything, but I do not remember having seen this type of pattern in earthquake activity in Katla volcano before. Currently the earthquake activity is almost none and that means that for now there’s no risk of an eruption.

Mýrdalsjökull glacier and the caldera shown as a elongated circle inside the glacier on the map from Icelandic Met Office. In the central caldera, there's a red dot showing the newest and largest earthquake of today.
Minimal earthquake activity in Katla volcano today (3. February 2023). Copyright of this image belongs to Icelandic Met Office.

Largest earthquake today (3. February 2023) had a magnitude of Mw2,7. This is what has been happening in recent months. This one or two earthquakes that are slightly larger than what I consider normal. There’s a chance this might be normal and nothing more is going to happen, but for now, it is impossible to know for sure what is happening.