Earthquake activity in Grímsfjall volcano

Early this morning at 06:53 UTC an earthquake with magnitude of Mw4,3 took place in Grímsfjall volcano. This is the largest recorded earthquake in Grímsfjall volcano since recording started in 1991. This happened soon after a glacier flood started from Grímsfjall volcano lake. This is a minor glacier flood.

Green star in Grímsfjall volcano. There's also an earthquake in Bárðarbunga volcano with a green star.
Earthquake activity in Grímsfjall volcano and in Bárðarbunga volcano. Copyright of this image belongs to Icelandic Met Office.

Experts are expecting an eruption from Grímsfjall volcano. However, it is my personal view that no eruption is going to happen during this flood like last time. The reason being that Grímsfjall volcano has entered different type of eruption cycle. Start of that eruption cycle was in the May eruption in 2011. Why that is I don’t know.

Earthquake swarm in Krýsuvík-Trölladyngja volcano

Today (03. January 2024) at 10:50 UTC an earthquake with magnitude of Mw4,3 took place in Krýsuvík-Trölladyngja volcano. A second earthquake with the magnitude of Mw3,5 took place at 10:54 UTC. Both earthquakes where felt in Reykjavík and up to Akranes and along the south Iceland (Selfoss, Hveragerði). A small earthquake swarm took place following the larger earthquakes.

Two green stars west of Kleifarvatn lake. Along with few red dots at almost the same location showing smaller earthquakes.
The earthquake activity in Krýsuvík-Trölladyngja volcano (green stars). Copyright of this image belongs to Icelandic Met Office.

This earthquake swarm seems to be somewhat ongoing, but has slowed down or almost stopped otherwise.

Donations

I no longer run ads. So if people want to help me. The best way to do so is to support my work with donations. Thanks. 🙂
Companies can buy ads on this website for a period of time, if they are reasonable ads. Since that also helps my work.

Update on Sundhnúkagíga activity for 2. January 2024

This update is going to be short. Information here might go outdated quickly and without warning. This article is written at 20:51 UTC on 2. January 2024.

Inflation in Svartsengi volcano has reached its maximum according to GPS stations compared to 18. December 2023. This inflation is not even among the GPS stations on top of Svartsengi volcano. Why that is unclear, but most likely reason is that the sills that are in Svartsengi volcano are not evenly filled this time around. Why that is I don’t know, something must have changed in the internal flow of this volcano when it comes to the sills.

It is difficult to know when next eruption happens, at the writing of this article I am looking at around seven day window at the moment. That an eruption should happen around 9. January 2024. It might happen sooner or it might happen later. It is difficult to know for sure. Where eruption is going to happen is impossible to know. It is expected that an eruption might happen again close to the last eruption took place or at the same location.

If anything happens. I’ll post update soon as possible. Next update for Sundhnúkagíga is going to be when something happens.

Donations

I no longer have Google Adsense, because it was no longer economic to use them. Because of new requirements and lower advertising income, that has been going down for a while (this is also happening on YouTube for people that create content there, they have videos on this). If people want to support my work, they can do so with a bank transfer, both inside and outside of Europe. That is the most safe option. The second option is to use PayPal, with all its problems and issue that might happen. Thanks for the support. 🙂

Update on Sundhnúkagíga on 27. December 2023 (includes information on Fagradalsfjall volcano)

This is a short update on the situation in Sundhnúkagíga on 27. December 2023 at 20:40 UTC. Information here can go outdated without warning and quickly.

There’s inflation taking place in Svartsengi volcano. At current rate this inflation is around 10mm a day. This means that earliest an eruption might happen is around 30. December 2023 in my view. But it might happen as late as 10. January 2024. This inflation is really quick, but since last eruption only lowered Svartsengi volcano only around 80mm, the inflow of magma has less space to fill up before a critical point is reached in the crust in Sundhnúkagígaröðin area. This also means it takes shorter time for this to happen.

Earthquake activity along the dyke from 10. November close to Grindavík town and there's also a earthquake swarm activity in a fault line in Fagradalsfjall volcano.
Earthquake activity along the dyke that was created on 10. November 2023 and in Fagradalsfjall volcano. Copyright of this image belongs to Icelandic Met Office.

There’s also activity in Fagradalsfjall volcano. This is along a fault line that I don’t think has been active like this before. Why is unclear, but this might be an early sign that this fault in Fagradalsfjall volcano might erupt in the future. Since Fagradalsfjall volcano is on around ten month eruption cycle, this fault might erupt sometimes between May to September 2024. I am sure that this is going to get more clear as the time goes on if anything is going to happen in Fagradalsfjall volcano. Satellite images from Google Earth do show a clear fault in along the earthquake active area. This is possibly a known fault, but I do not have any information about that as is.

Earthquake activity along the dyke shown in higher resolution along the dyke from 10. November 2023. An earthquake activity in Fagradalsfjalli volcano east of Svartsengi and Sundhnúkagígar on a small faultline there.
Earthquake activity for the last 8 days in Sundhnúkagígaröðin and in Fagradalsfjalli. Image from Skjálfta-Lísa. Copyright of image belongs to Icelandic Met Office.
A crack in the ground on satellite image from Google Earth in Fagradalsfjall volcano.
Crack in the ground on Google Earth image of Fagradalsfjall volcano. Copyright of this image belongs to Alphabet/Google Earth.

It is impossible to know what happens in Fagradalsfjall volcano and in Svartsengi volcano. This situation can change quickly and without warning. It can change so quickly that I might not be able to update about it quickly enough if this happens at a time when I am outside doing something else.

If anything happens. I’ll update soon as I can do so. Next update should be on 2. January 2024 if this remains quiet.

Update on Sundhnúkagígar on 22. December 2023 at 20:49 UTC

This is a short update and information here might go outdated quickly and without warning. This update is written on 22. December 2023 at 20:50 UTC.

Inflation has resumed in Svartsengi volcano. It also seems that inflation started again just before the eruption ended in Sundhnúkagaígar. At the writing of this article, the inflation is only around 5mm to 8mm a day. That is fast, by any standard, but still lower than before the eruption when inflation was around 10mm a day. There seems to be a slowdown of inflation before an eruption happens and a new dyke creations. Not all dyke that are going to happen are going to end in a eruption, maybe, since the magma has only limited space to expand into in the rift valley, because of the dyke that was created on 10. November 2023.

Red dots along the rift valley and orange dots from the earlier earthquakes today.
Earthquake activity along the rift valley today. This is a lot of earthquake activity. Copyright of this image belongs to Icelandic Met Office.

Earthquake activity along the rift valley increased quickly as the eruption that started on 18. December 2023 started to slow down. That means the magma in Svartsengi volcano is trying to find a way out and erupt all at once, or close to that in my personal view. The 4,1 km long fissure that erupted last time doesn’t seems to have been a enough for the pressure that is in the volcano at the writing of this article. That is interesting but might also be a clue that things are about to get really dangerous in this area. I also don’t know if this is going to happen, because clues are one thing and reality is a different thing.

If anything happens. I am going to write an article soon as I can.

Update on Sundhnúkagígar activity on 21. December 2023 at 18:47 UTC

This is a short article, written on 21. December 2023 at 18:47 UTC. Information here might go outdated quickly and without warning.

The eruption that started on 18. December 2023 at 22:17 UTC is over, best I can see. This was large eruption, but a short one. Total lava flow covered an area of 3,7 km2 (square kilometre). Most of the eruption happened in the first 24 – 48 hours of the eruption. There are early indicators that inflation has resumed in Svartsengi volcano, if it inflates at the same rate as before this eruption it is only going to take 8 to 10 days until next eruption. This is a big question since there’s a lot of magma in Svartsengi volcano and that magma can move towards the surface, even if the inflation doesn’t happen and can result in a larger eruption. If that happens is a wait and see situation.

Videos from the eruption areas show a lot of degaussing in the eruption fissure. This is interesting and I am not sure why that is. There’s a chance a lot of magma is in the dyke that is just releasing gas into the air without having the energy to erupt. There’s a small chance that a new eruption might happen in the same location. If that happens is impossible to know.

Red dots and yellow dots in the rift zone valley where the eruption just ended. Time on image is 21. Des. 2023 at 19:15 UTC.
Earthquake activity along the rift valley. Copyright of this image belongs to Icelandic Met Office.

This earthquake activity is interesting, it started yesterday (20. December 2023). This follows the same pattern as the earthquake activity before the start of the eruption on 18. December. If that is what is happening remains a wait and see situation for now.

This is the last update unless something happens in this area. Based on current information, that is what is going to happen, the question is just when.

Update for Sundhnúkagígar eruption on 20. December 2023 at 18:29 UTC

This is a short update and information here might go outdated quickly and without warning.

This eruption is a short one and that’s how eruptions in Iceland are normally. This eruption might end by Friday to Monday, depending on what happens.

  • The flow from the craters that are erupting is around 10m3/sec. This is low compared to the start of the eruption on Monday 18. December 2023 and suggest that this eruption is going to end soon.
  • GPS data shows that Svartsengi volcano has only lowered around 80mm since Monday. This means there’s a lot of lava in Svartsengi for new eruptions to happen without much warning.
  • Earthquake activity along the fault valley has resumed, after stopping soon after the main eruption took place. This is interesting and I am unclear what this means at the writing of this article.
  • Icelandic Met Office is reporting that the eruption, even is small, is stable at the writing of this article. This can change without warning.
  • The lava field is now, according to best measurements around 3,7 km2 (square kilometres).
  • According to University of Iceland Earth science department, the chemical makeup of the lava shows that its more evolved in part than the lava in Fagradalsfjall volcano. This can be read here (new link, now in English). This means that this magma stopped on its way to the surface and cooled a little and changed chemical makeup before erupting.
  • This new lava is different than the lava that erupted 2400 years ago at the same location. Why that is I don’t know. It is going to take few years to maybe get an answer to this question when the experts have done their research and published their science papers.
Earthquake activity along the rift valley in Svartsengi volcano shown by a green stars, red and orange dots showing smaller earthquakes.
Earthquake activity along the rift valley. Copyright of this image belongs to Icelandic Met Office.

It is interesting to see that Þorbjörn mountain continues to get lower, based on GPS data from today (20. December 2023). Icelandic Met Office has released new danger map and that can be found here in English on Icelandic Met Office website.

This is all the information I know of today (20. December 2023). Next article should be tomorrow (21. December), unless something happens then I’ll try and write article soon as I can.

Update on the eruption in Sundhnúkagígar on 19. December 2023 at 21:46 UTC

This is a short update and information here might go outdated quickly. This article is written on 19. December 2023 at 21:46 UTC.

I am trying to collect and read all the information I can find. I don’t have access to everything my self, so I am depended on news and reports from Icelandic Met Office and others on what is happening in this eruptions. This is not unusual and has always been like this.

  • The eruption is now in 2 to 4 vents. I am little unclear at the writing of this article now many are erupting.
  • The new dyke seems to go into the dyke from 10. November. This can result in reactivation of the dyke from 10. November and result in an eruption along it, all 15 km at random location.
  • Current flow seems be around 50m3/sec at the writing of this article. I’ve been hearing that highest flow yesterday (18. December) was around 800m3/sec, but that number is for me unconfirmed. It dropped to 100 – 500m3/sec soon after the eruption started.
  • Early GPS data from today seems to suggest that Svartsengi volcano has lowered about 50mm since the start of the eruption. I am waiting for new GPS data on Icelandic Met Office website. That data hopefully shows up tomorrow (20. December).

There’s a lot of uncertain things that can happen with this eruption at the moment. Since there’s a lot of lava in Svartsengi volcano that has not erupted so far. New inflow of lava from the deep mantle is also a possibility and those can happen without warning as the pressure drops in Svartsengi volcano sill (or magma chamber).

I’ll post next update tomorrow (20. December 2023) or sooner if anything happens.

Update on the eruption at Sundhnúkagíga on 19. December 2023 at 16:10 UTC

This article is short and is written at 16:10 UTC on 19. December 2023. Information here can go outdated quickly and without warning.

There has been a reduction in the eruption since it started at 22:17 UTC on 18. December 2023. This was to be expected. Since the eruption seems to be coming from a small sill in Svartsengi volcano, rather than a large magma chamber.

  • The eruption is now limited to three to four eruption vents. The largest one is where the eruption started. Crater building is ongoing.
  • The lava is flowing towards Fagradalsfjall volcano (mountain) at the writing of this article. This area is empty, outside of the the parking lots south of Fagradalsfjall. They are not at risk for now.
  • The problem with eruptions of this type is that they can grow again in size if different sill breaks and starts flowing into the established flow channels that magma is now flowing and creating the eruption. If that happens is impossible to know. This can also result in a eruption that goes on for a long time. If that happens, an lava might end up reaching far away areas.
  • It is going to take few days for GPS data to show what sill is deflating in Svartsengi volcano and what is going on in the crust in Svartsengi volcano.
  • Weather might be a problem for next few days on Reykjanes peninsula.
  • This area is not to hike around on. Its dangerous and the weather makes difficult walk extremely difficult.  Just watch the online web cameras.
  • The lava field is large and it creates its own strong wind as the lava warms up the air around it. That can be difficult to deal with in the snow for anyone close the the eruption.

The dyke is longer than the part that erupted according to the news and measurements. The dyke is more south and it ends just 1,5 km north of Grindavík town. That area can erupt without warning if pressure starts to build up in that part of the dyke. That same goes for the north part of the dyke, how far more north the dyke is I don’t know.

I’ll post next update when I have more information what is going on or sooner if anything happens.

Update on the eruption in Sundhnúkagíga on 19. December 2023

This article is written on 19. December 2023 at 02:35 UTC. Information in this article can go outdated quickly and without warning.

  • The fissure is at last measurement around 4000 meters long (4 km) according to the news.
  • The volcano that is erupting is Svartsengi volcano. On some maps this is shown as Reykjanes volcano.
  • This is the largest eruption on the Reykjanes peninsula  so far.
  • The lava flow is mostly to the east, a way from infrastructure and roads. This is mostly, but can change without warning.
  • There’s a lot of gas pollution from this eruption. This gas is dangerous to people and animals.
  • The lava flow from the fissure is around 100m3/sec to 200m3/sec.
  • The fissure has started to form crates. This is going to continue to create craters as the eruption goes on.
  • There’s a ongoing risk that the eruption fissure might extend to the south towards Grindavík. If that actually happens is impossible to know.

I am going to write next update sometimes later today (19. December 2023) when I have new information and more is known about this eruption.