Strong earthquake close to Húsafell

Today (1-February-2022) at 00:05 UTC an earthquake with magnitude of Mw3,7 took place close to Húsafell. This earthquake was felt in Reykjavík. This earthquake swarm is ongoing, it is slow moving and often stops A second earthquake with magnitude Mw3,0 took place at 01:15 UTC. During the last 48 hours a total of 107 earthquakes have happened in Húsafell area.

Two green stars west of Langjökull glacier with smaller earthquakes in the same area
Earthquake activity in Húsafell. Copyright of this image belongs to Icelandic Met Office.

Largest known earthquake in this area has a magnitude of 5,5 in the year 1974. That is all I know about this earthquake, that earthquake was also slightly more north then current swarm. Why this earthquake activity is happening is unclear since there are not any known volcanoes in this area or earthquake faults. There is a low (as in degrees of hot water) hydrothermal area in this area and recent news articles have suggested that this earthquake activity might be connected to that area. That is at best speculation and nothing has been proved so far. The existence of this low hydrothermal area shows that magma is in the crust in this area at shallow depth and has been for a while. For hydrothermal area to form, both cracks in the crust needs to be open and magma needs to reach 1 to 2 km up in the crust to warm up ground water in the crust.

Earthquake swarm south-west of Langjökull glacier

Since December 2021 an earthquake swarm has been ongoing south-west of Langjökull glacier. This area is not part of any known fault zone or any volcano. This is just tectonic earthquakes and is outside of main earthquake areas. This intra-plate earthquakes happens sometimes in Iceland. Why that is remains unknown, but best idea is this happens because of stress changes because of tectonic movement. Earthquake magnitude can go up to Mw5,5 or larger. But such events are extremely rare, but do happen.

Earthquake swarm south-west of Langjökull glacier. Green star shows a magnitude Mw3,3 earthquake
Earthquake south-west of Langjökull glacier. Copyright of this image belongs to Icelandic Met Office.

This is the second earthquake with magnitude Mw3,3 in this area, with the earlier one happening on 18th January 2022. The hill this earthquake swarm is happening in is called Húsafell.

The Hunga Tonga-Hunga Ha’apai explosion on 15-January-2022

This is a special article about the eruption and the explosion in Hunga Tonga-Hunga Ha’apai volcano, close to Tonga in the Pacific Ocean. I don’t know a lot about this volcano so I might get details wrong. This is also not a long article, because of lack of my knowledge. Because of copyright, I can’t use any images in this article.

At 04:00 UTC on 15-January-2022 an eruption started in >Hunga Tonga-Hunga Ha’apai volcano, that is 65 distance from Tonga islands (population around 100.000). In what seems to be a process that only took about 1 to 3 hours, the eruption exploded with largest eruption force in modern history. This is possibly largest eruption since 1912 (Alaska) in the world or even largest eruption since Krakatoa in 1883. According to articles, research into this volcano suggest that it has an explosive period eruption phase every 1000 years, the last one being around the year 1100. The length of this eruption seems to have been 3 to 5 hours in total and in last 24 hours there have been reports of a lot smaller eruptions happening. Each of them only lasting few hours at most.

When the explosion happened it created a tsunami that hit Tonga few moments later with waves up to 1,13 meters high and Fiji islands where it with waves that where around 80 cm high (reports). Around 13 hours later, the tsunami hit the west coast of the United States and Canada, Los Angeles area and other coastal areas. The sound wave that followed was heard clearly 2300 km away in New Zealand and in Alaska at distance of 9373 km, the explosion was also heard clearly in Fiji islands that are in 700 to 1000 km distance. The air pressure wave that happened during the explosion did go over the Earth two times, it was detected in Iceland at around 17:00 to 18:00 on 15-January-2022 and the second wave was detected on 16-January-2022 at around 05:00 to 06:00 in Iceland.

It is going to take years to understand the size and effects of this volcano explosion because how remote it is, since it is out in the ocean and next populated area is 65 km away and that’s the only monitoring of this volcano, since other options are not possible for monitoring of Hunga Tonga-Hunga Ha’apai volcano.

The effects of the explosion was largest in Tonga that is now cut off from the internet because of damage to undersea fibre cable that connects them to the internet. How long that repair work is going to take depends on a lot of things, but it can take weeks or months until fibre connection is restored. There was also a lot of tsunami damage in Tonga, how extensive it is I don’t know because of lack of reports.

This is all I have for now on this eruption. I don’t know if I’ll write another article about this event, since I only cover world events that are major events and this volcano explosion has been classified in my system as a major volcano event.

More detailed article with images of the volcano

Why the volcanic eruption in Tonga was so violent, and what to expect next (The Conversation)

Magma on its way up the crust in Fagradalsfjall mountain, last measurements shows 1600 meters left (1,6km)

According to a news on Vísir.is (linked below) the magma has started to rise in Fagradalsfjall mountain. At the time of the measurement from a satellite the magma had around 1600 meters (1,6km) left until it reached the surface. At the speed the magma was travelling, around 130 meters a day an eruption was expected to happen around 11-January-2022. This is the current estimate, but that might change of the magma increases or slows down the speed it is going up in the crust.

It is unclear what area is going to erupt since the new dyke is more alongside the older eruption dyke. There is more chance than less that new craters are going to open up and start erupting, some of the area is under fresh lava from earlier eruption. Making the area look interesting when this eruption starts.

Icelandic News

Kvikan á uppleið en á enn 1.600 metra eftir (Vísir.is)

Felt earthquake on South Icelandic Seismic zone

During the night of 30-December-2021 at 04:16 UTC an earthquake with magnitude of Mw3,0 was felt in Selfoss town and Hveragerði town. This earthquake was part of a swarm in the area that is ongoing at the writing of this article.

Green star on the far right on the map with few red dots, showing the earthquake activity in SISZ
Earthquake activity in SISZ. Copyright of this image belongs to Icelandic Met Office.

There are no volcanoes in this area so this is only a tectonic activity. It is not possible to know when this earthquake swarm ends. This might be a aftershock activity after the Mw6,3 earthquake in SISZ that took place in this location in the year 2008. I expect this earthquake swarm to continue to few more days to weeks and then just end quietly.

Earthquake swarm in Bárðarbunga volcano

Today (29-December-2021) at 14:46 UTC an earthquake with magnitude of Mw3,6 (Icelandic Met Office) or magnitude of mb4,5 (EMSC website information here).

Green star in Vatnajökull galacier in Bárðarbunga volcano. Few red dots show smaller earthquakes that also happened in Bárðarbunga volcano
Earthquake activity in Bárðarbunga volcano. Copyright of this image belongs to Icelandic Met Office.

This earthquake activity is normal and is because of inflation that is now happening in Bárðarbunga volcano. Eruption is not going to happen now. It might be few more years or few more decades until that happens.

Strong earthquake activity in Fagradalsfjall mountain, Krýsuvík-Trölladyngja volcano

This information is going to get outdated quickly.

There is now a constant earthquake swarm activity in Fagradalsfjall mountain, part of the Krýsuvík-Trölladyngja volcano system. More than a dozen of earthquakes have been larger than magnitude 4,0 and it doesn’t look like this earthquake activity is doing to stop soon. Largest earthquakes in last few hours had a magnitude of Mw4,8 and Mw4,5. The earthquake north of Grindavík town appears to be a tension breaking earthquakes because of magma inflation in Fagradalsfjall mountain.

A lot of earthquakes on Reykjanes peninsula, more than a dozen green stars, hundres of red dots showing smaller earthquakes
The earthquake activity on Reykjanes peninsula. Copyright of this image belongs to Icelandic Met Office.
Heavy earthquake activity shown on Icelandic Met Office earthquake tracker. The density of earthquake activity has the image swamped with activity
Earthquake activity on Reykjanes peninsula in Fagradalsfjall mountain for the last 48 hours. Copyright of this image belongs to Icelandic Met Office.

This earthquake swarm is close to Grindavík town, this is a similar situation that happened earlier in the year 2021. Just before the eruption in Fagradalsfjall mountain. This earthquake activity is going to continue to grow until an eruption starts. This earthquake activity also happens in a wave, resulting in it lower earthquake activity between powerful earthquake activity. I am expecting more strong earthquakes in next few days, unless an eruption starts in Fagradalsfjall mountain or nearby area.

Update on activity in Krýsuvík-Trölladyngja volcano in Fagradalsfjall mountain, eruption is going to happen soon

Information here are going to get outdated quickly.

The earthquake activity in Fagradalsfjall mountain continued on 22-December and on 23-December-2021. Largest earthquake in last few hours had a magnitude of Mw4,9 and was felt over a wide area. No property damage has yet happened because of this earthquake activity so far.
There are now three centres where the earthquake activity is happening. The first one is north of the large crater, the second one is under the main crater and the third one is in Nátthagakrika (about south-west of the large crater). This is the area where people used to walk up the eruption on walking paths A and B.

Dense earthquake activity on Reykjanes pensiula with lot of earthquakes and green stars and red dots
The heavy earthquake activity on Reykjanes peninsula. Copyright of this image belongs to Icelandic Met Office.
Plot showing the magnitudes of the earthquake and density. A lot of earthquake that go above 3 line and dense dots with smaller magnitudes
The density of the earthquake activity in the current earthquake swarm. Copyright of this image belongs to Icelandic Met Office.

This earthquake activity is not going to stop until an eruption starts. When that happens is not possible to know. If a new crater opens up that is going to result in ever growing and stronger earthquakes. If the crater that is already in place starts erupting again, that is going to result in some earthquake activity. What is known is that the magma is going to go the path of least resistance, whatever that path might be. At the writing of this article, over 6000 earthquakes have been recorded and around 50 to 100 of them have been larger than magnitude 3,0.

Earthquake swarm in Krýsuvík-Trölladyngja volcano, close to Fagradalsfjall mountain, eruption possible soon

This information is going to get outdated soon. Since the situation is changing quickly.

It is possible that a new eruption is about to start in Fagradalsfjall mountain in Krýsuvík-Trölladyngja volcano. This earthquake activity started around 17:00 UTC on 21-December-2021 and has been growing since then. At the writing of this article the largest earthquake had a magnitude of Mw3,3. Over 150 earthquakes have been recorded at the writing of this article. This earthquake activity doesn’t seems to be slowing down.

Earthquake activity in Fagradalsfjall, a lot of red dots, green star shows the largest earthquake
Earthquake activity in Fagradalsfjall mountain. Copyright of this image belongs to Icelandic Met Office.

The situation is changing quickly. As of writing this article a new eruption has not yet started but that might only be question of hours until an eruption starts. This might happen during the night or sometimes tomorrow during the day. There is not any way to know that for sure at the writing of this article.

I’ll post update late tomorrow if this changes and a eruption starts. Since I’ll be busy during the day the late article can’t be helped.