Posts

Posted on

Earthquake swarm in Brennisteinsfjöll volcano

Today (21-October-2022) an earthquake swarm took place in Brennisteinsfjöll volcano. Largest earthquake had a magnitude of Mw3,0 at 10:23 UTC. This earthquake swarm is possibly over, it is however difficult to be sure.

Red dots in Brennisteinsfjöll volcano on Reykjanes peninsula, located just south of Reykjavík city and east of Kleifarvatn lake. A lot of yellow and orange dots on the map in few volcanoes showing smaller earthquake activity
Earthquake activity in Brennisteinsfjöll volcano and other nearby volcanoes. Picture is from Icelandic Met Office.

This is probably just a tectonic earthquake activity. But it is worth noting that volcano activity as has been seen in Fagradalsfjall volcano (Iceland newest volcano) is going to move east on Reykjanes peninsula. How fast and how long that change is going to happen is not known because of lack of data and written records from 700 to 900 years ago are incomplete and vague on details at best.

Posted on

Earthquake swarm north of Grímsey island

Today (19-October-2022) at 10:26 UTC an earthquake with magnitude of Mw3,8 took place and at 11:58 UTC an earthquake with magnitude of Mw3,3 took place at the same location. I don’t know if any of the larger earthquakes where felt. A swarm of smaller earthquakes took place and that activity is ongoing when this article is written.

Two green stars north of Grímsey island in Tjörnes Fracture Zone. This is out in the ocean far from land and populated areas.
Earthquake activity north of Grímsey island. Picture is from Icelandic Met Office.

This earthquake activity probably is continuation of an large earthquake swarm that started in that area in September. I don’t know if this is going to result in more stronger earthquakes, but that is a possibility.

Posted on

Strong earthquake swarm on Reykjanes ridge close to Geirfugladrangur and Eldeyjarboða

This evening on 16-October-2022 an strong earthquake swarm started close to Geirfugladrangur and Eldeyjarboða on the Reykjanes ridge. At the writing of this article the strongest earthquake had a magnitude of Mw4,4 but that might change without warning.

Red dots and green stars on the Reykjanes ridge out on the ocean. Reykjanes peninsula on the left side of the image
Earthquake activity close to Geirfugladrangur and Eldeyjarboða on the Reykjanes ridge. Image from Icelandic Met Office.

It is difficult to know how this earthquake swarm is going to evolve but there are clues in this activity that this might be a large earthquake swarm. However, activity in this area is also known to just stop without warning.

Posted on

People advised not go to Mýrdalsjökull glacier

The police and Icelandic Met Office have now advised people not to go to Mýrdalsjökull glacier. This is after the earthquake swarm earlier today. According to Icelandic Met Office this earthquake swarm is similar to what happened before the minor eruption in Katla volcano in July 2011 that resulted in a glacier flood down Mýrdalssand and destroyed the bridge over the glacier river in that area. All trips to see ice caves in Mýrdalsjökull glacier have been temporarily forbidden by the Icelandic Police.

Two green stars and few red dots in Katla volcano caldera on the east side of the volcano under Mýrdalsjökull glacier
Earthquake activity in Katla volcano. Copyright of this image belongs to Icelandic Met Office.

In July 2011 it took around 24 hours from the start of the earthquake activity then until something happened. If that is going to be case now I don’t know. That this activity is similar to July 2011 eruption is worrying. The eruption in July 2011 was minor and didn’t break the glacier, but it resulted in damage in that area from the glacier flood.

Largest earthquakes now have the magnitude of Mw3,8 and Mw3,0 (few of them). Other earthquakes have been smaller in magnitude but that might change without warning.

Posted on

Earthquake swarm in Katla volcano

Today (16-October-2022) an earthquake swarm started in Katla volcano in Mýrdalsjökull glacier. Largest earthquake at the writing of this article had a magnitude of Mw3,8. I don’t know if it was felt in nearby towns and farms. Second largest earthquake had a magnitude of Mw3,0.

Green star and red dots in Katla volcano caldera that is covered with Mýrdalsjökull glacier.
Earthquake activity in Katla volcano. Copyright of this image belongs to Icelandic Met Office.

This earthquake swarm is ongoing at the writing of this article and the situation can change quickly. This might be a normal earthquake swarm and nothing more might happen. This type of earthquake swarm is not uncommon and I am not sure what is required for an eruption to start in Katla volcano.

Posted on

Something is going on in Grímsfjall volcano

This is a tricky thing to write about. Because nothing has started on the surface and might not start on the surface. It seems that something is going on in Grímsfjall volcano. Since the glacier flood is almost over or has finished the harmonic tremor level should have started dropping, it has not done so and I am not sure why that is. This might be boiling of the hydrothermal systems in Grímsfjall volcano when the pressure on the suddenly drops. Currently the harmonic tremor doesn’t look like it has reached eruption levels, that might change without warning.

Rising harmonic tremor, with a high top from storm noise on the 10/10. Colours are blue, green and purple that is barley visible at the end of the line.
Harmonic tremor in Grímsfjall volcano. Copyright of this image belongs to Icelandic Met Office.
One red dot in Grímsfjall volcano in middle of Vatnajökull glacier shown by white area on the map
Earthquake activity in Grímsfjall volcano. This is almost no earthquake activity. Copyright of this image belongs to Icelandic Met Office.

It is difficult to know what is going on. Since there seems to have been a change in Grímsfjall volcano after the big eruption in May 2011. What that change is I don’t know. It seems to have slowed down Grímsfjall volcano eruption rate from what it was, its been 11 years since last eruption. It might continue if no eruption starts now following the small glacier flood that just ended.

Posted on

Earthquake swarm south and east of Grímsey island

Yesterday (12-October-2022) an earthquake swarm started south and east of Grímsey island. This is in the same area as an earthquake swarm took place few weeks ago. Largest earthquakes so far in this swarm had a magnitude of Mw3,5. Larger earthquakes remain a possibility. Largest earthquakes have been felt in nearby populated areas.

Red dots east and south of Grímsey island along with two green stars that show the largest earthquakes. On a blue background and the coastline is fjords and small peninsuals in north-eastern Iceland.
Earthquake activity south of Grímsey island. Copyright of this image belongs to Icelandic Met Office.

This area has frequent earthquakes. This earthquake swarm might grow as sometimes happens. It might also equally just stop, since that is also something that earthquake swarm in this area do.

Posted on

Magnitude Mw3,5 earthquake in Krýsuvík-Trölladyngja volcano

Today (12-October-2022) at 14:18 UTC an earthquake with magnitude of Mw3,5 took place in Krýsuvík-Trölladyngja volcano. This earthquake was followed by few smaller aftershocks. This earthquake seems to be happening because of a inflation that is taking place in Fagradalsfjall volcano and this strongly suggests that inflation in Fagradalsfjall volcano is slowly reaching critical levels. There is no eruption expected from Krýsuvík-Trölladyngja volcano as is.

Green star with few red dots just west of Kleifarvatn lake, showing increase in activity in Krýsuvík-Trölladyngja volcano
Earthquake activity in Krýsuvík-Trölladyngja volcano. Copyright of this image belongs to Icelandic Met Office.

This earthquake activity suggests that more stronger earthquake activity is possibly on the way. When it might start is difficult to know for sure. This has been the pattern in recent months. Earthquake activity starts to appears like this and then one day a major earthquake swarm starts. What happens now is a wait and see as before.

Posted on

Small glacier flood from Grímsfjall volcano expected tomorrow (11. October 2022)

According to a news on Rúv. A small glacier flood is expected from Grímsfjall volcano tomorrow. This glacier flood is not expected to create any problems for roads or bridges. Last glacier flood took place in December 2021. The glacier flood is expected to appear in the glacier river Gígjukvísl.

Icelandic news and announcement of the glacier flood

Lítið hlaup úr Grímsvötnum (Icelandic, Icelandic Met Office)
Von á litlu hlaupi úr Grímsvötnum á morgun (Icelandic, Rúv.is)

Posted on

Earthquake activity has started to increase in Fagradalsfjall and Reykjanes volcanoes

Since yesterday (06-October-2022) the earthquake activity has been increasing in the volcanoes Fagradalsfjall and Reykjanes volcanoes. Please note that Global Volcanism Program has updated the informations regarding Fagradalsfjall mountain and now classifies it as its own volcano, this is after a new report and information from Icelandic Met Office. From now on I am going to use that classification when updating on activity in Fagradalsfjall volcano. I’ll not update older articles (too much work), but this also applies to them as such.

This also means that Fagradalsfjall is a new volcano in Iceland.

Earthquake activity in Fagradalsfjall volcano, Krýsuvík-Trölladyngja and Reykjanes volcano. Shown with red, orange and blue dots
Earthquake activity in Fagradalsfjall volcano and Reykjanes volcano along with Krýsuvík-Trölladyngja volcano. Copyright of this image belongs to Icelandic Met Office.

Earthquake activity at start of an eruption cycle in Fagraldsfjall volcano are not large. They grow larger once magma has started to push into the crust, until then the earthquake activity only seems to happens with minor earthquake swarms.

Article updated with new information.

Donations

Please remember to support my work with donations. This month I am really broke. Thanks for the support. 🙂