Earthquake swarm close to Eldeyjarboða on Reykjanes ridge

Today (9. December 2023) at 05:55 UTC to 06:44 UTC an earthquake swarm took place deep on the Reykjanes ridge. This earthquake swarm is far from the coast so smaller earthquakes where not detected by Icelandic Met Office. Largest earthquake in this swarm had a magnitude of Mw3,8.

Green star and yellow dots far from the coast of Reykjanes peninsula. This is far out in the ocean.
Earthquake activity deep on Reykjanes ridge. Copyright of this image belongs to Icelandic Met Office.

This is in a volcano, its unclear if this is in the volcano Eldeyjarboði or a different unnamed volcano. This earthquake swarm seems to have stopped by now.

Update on Grindavík 24. November 2023

This is a short update on the situation in Grindavík and nearby area on 24. November 2023. This article is written at 18:47 UTC.
Information in this article can go outdated without warning and quickly if something happens.

This activity has slowed down for now. This means I am going to be posting update less here, unless something changes and that can happen without warning.

Daily update

  • There is movements on cracks and new holes and cracks are opening up or appearing as the ground collapses and exposes the fissure.
  • Earthquake activity has reached a low point. This might be just for a short period of time.
  • The inflation in Svartsengi is today around 140 to 160mm from 10. November 2023. The inflation each day is around 30 to 40mm.
  • The area that is inflating in Svartsengi is larger now compared to the area that inflated before 10. November 2023. This has created a uncertainty in the GPS data as I understand the situation. The rift valley is also creating issues in the GPS data as parts of him continue to sink and are going to continue to sink and lower nearby area with it. How much that is difficult to know.
  • The event that happened on 10. November 2023 was the quickest event to happen in recorded history of Icelandic Met Office. According to their report and the news.

It is my view that the current low is just going to last for few more days, at most few weeks because of the ongoing inflation in Svartsengi. It is my view that it is going to take around 30 days until next dyke activity happens, that is around 10. December when that might happen. But the situation is changing quickly and impossible to know for sure how it develops in next few days to weeks.

If anything happens. I’ll post update soon as I can do so.

Update on Grindavík for Wednesday 22. November 2023

This is a short update. Information there might go outdated quickly and without warning. This article is written on Wednesday 22. November 2023 at 21:32 UTC.

There’s little news to report at this moment. Mostly because of bad weather. The progress of the dyke has also stalled from earlier, or this might be it for now. It is difficult be sure currently.

Risk map of Grindavík and the total of 15 km in both directions. The red zone, danger zone b has been withdrawn to north of Grindavík and now its just a small line north of the town and up north along the dyke. The most dangerous risk zone is north of the town.
The risk zone around Grindavík. Copyright of this image belongs to Icelandic Met Office.

The inflation at Svartsengi (upwards movement) stopped in the last 24 hours. This either means this series of events is stopping for now or something major is about to happen. I am not sure. Risk of this being a error are small, but this might be interference from weather (rain, snow).

The air code for Reykjanes volcano has been downgraded to yellow.

Aviation colour code for volcanoes in Iceland. All are green except Reykjanes volcano that is now yellow.
The aviation colour code of volcanoes in Iceland. Copyright of this image belongs to Icelandic Met Office.

The situation in Grindavík and in Sundhnúkagígar and the nearby area can still change without much warning. Since the ground is very fractured there and is not going to be much resistance to any magma movements in the near future.

If anything more happens. I’ll update soon as I can.

Update for Grindavík on Monday, 20. November 2023

This is a short update on the situation in Grindavík. This article is written on 20. November 2023 at 22:22 UTC.

Storm warning

There’s a storm in Iceland until 23. November 2023. When the wind is going to start die down again. This means that Icelandic Met Office is going to record fewer earthquakes because strong ocean waves and wind.

Daily update

  • There has not been much change since yesterday. This is normal.
  • Inflation in Svartsengi is up to 30mm/day and this is a increase, since inflation used to be around 15mm/day.
  • Since Friday 10. November 2023 the inflation in Svartsengi has been around 150mm over the last 11 day time period.
  • It took 17 days from start on October 25 of the magma inflow into the Svartsengi dyke until it broke on 10. November and the created the Sundhnúkar to Grindavík dyke.
  • It is a question what happens when next 17 days come up. Because whatever the hold is for the magma in the dyke in Svartsengi is going to break it is going to start the process as happened on 10. November 2023 and possibly into the current dyke, or possibly create a new dyke next to the current one (its a possibility, not a large one, but it is there).

Other updates

There has not been a lot of information released today and I don’t see a lot on seismometers and other instruments around Grindavík town currently.

This is a image of the danger zone around Grindavík and north of it. Its divided into three zones. With the colours orange, red, purple.
The current danger zone map from Icelandic Met Office. Zone A (orange) is the least dangerous area. Zone B (Red) is a dangerous zone, risk of fissures opening up, erupting crates, lava flows and gas pollution. Zone C (purple) is the most dangerous zone, Its close to same as zone b, but increased risk of dangerous volcano gases and entering it requires wearing a gas mask, have a gas and have gas measurement tool when going into the zone. Red dotted line is the estimated location of the dyke. This map also shows fissures in this area and the rift valley. Copyright of this image belongs to Icelandic Met Office.

This type of quiet period before an eruption are common. Why is not well understood. Eruption might not happen, but it is not likely that nothing is going to happen in this. Both is magma too close too the surface and there’s too much inflow of magma into the dyke at Svartsengi. This is how I see the current situation.

If anything happens. I’ll post update soon as I can.

Update on Grindavík on 19. November 2023

This is a short update on the activity in Grindavík on 19. November 2023. Information here might go out of date without warning. This article is written at 22:28 UTC.

Krýsuvík earthquake

This morning an earthquake with magnitude of Mw3,7 took place in Krýsuvík-Trölladyngja volcano. This earthquake was felt in Reykjavík area. This earthquake happens because of all the displacement that is now happening next to Grindavík town.

Green star west of Kleifarvatn lake. The dyke appears as a red line with a lot of smaller earthquakes.
The earthquake activity in Krýsuvík-Trölladynga volcano. Copyright of this image belongs to Icelandic Met Office.

Daily update

This is also an update for 18. November 2023. I was trying to get a little time off from writing.

  • Little has changed in last two days. Parts of Grindavík town continue to sink or rise depending on location. Most measured movements is around 25 cm last I did see. If that is correct today I am not sure.
  • Inflation in Svartsengi is around 130mm since Friday 10. November 2023 according to GPS measurements and satellite measurements.
  • Inflow of magma into Svartsengi is estimated to be around 50m3/sec when this article is written according to the news. Inflow of magma into the dyke was 75m3/sec or more few days ago. That has possibly changed to a lower number in last few days.
  • Earthquake activity remains about the same in the dyke. Around 800 to 2000 earthquakes a day along the 15 km long dyke.
Image that shows inflation in Svartsengi area on Reykjanes peninsula. This is a red area that has been lifting up 30mm/day. The image shows also colour blue and green. With blue showing area lowering and green and yellow area uplifting.
Inflation on the Reykjanes peninsula. Copyright of this image belongs to Icelandic Met Office.

It is impossible to know when this area is going to erupt. It can take up to three to four weeks to happen. It might be a shorter time period, it is impossible to know what happens when it comes to volcanoes and dyke activity.

If anything happens. I’ll post an update quickly as I can.

Update on Grindavík 17. November 2023

This is a short update on the situation in Grindavík on 17. November 2023. Information here can go outdated quickly and without warning.

Daily updates

  • Grindavík town continues to sink as the rift valley continues to move. The speed of sinking has slowed a little according to the news today.
  • Earthquake activity has slowed down in last few hours (this is written around 22:51 UTC). What that means is unclear.
  • Some houses in Grindavík town have been completely destroyed. Iceland has a natural disaster fund for this type of situation and that is going to cover the owners loss according to the news.

General update

It took me a week. But it seems that this dyke intrusion under Grindavík town is because of the magma sill (dyke) under Svartsengi. That area has inflated around 110mm in a week. That is a inflation of 15mm/day based on my best calculations. That is a lot of inflation, since before 10. November the inflow of magma into Svartsengi was at most 8m3/sec according to measurements of Icelandic Met Office.

The sill in Svartsengi created a lateral dyke in Sundhnúkar and nearby areas. When the pressure in the sill is high enough again it is going to push the magma into the dyke at Sundhnúkar again with the same force as it did before. How long that takes I don’t know. Last time this was from 25. October to 10. November. That’s seventeen days, but there was a lot of deeper sills in Svartsengi and its impossible to know much, if anything flowed form them into the dyke. This is my personal view, it might be wrong. But this is what I am reading from the data.

Risk of the eruption remains high because there’s a ongoing inflation at Svartsengi. When a eruption starts is impossible to know.

If anything happens. I’ll post update soon as I can.

Update on Grindavík on 16. November 2023

This is a short update on what is happening in Grindavík on 16. November 2023. Information here can go outdated quickly and without warning.

The situation is mostly the same as yesterday (15. November 2023), but few things have happened and that is enough for me to publish this article.

  • Sulfur dioxide has been detected in a drilling hole in Svartsengi. This drilling hole is such that it end point is close to Hagafell mountain  east to Svartsengi power plant. I think this might be a cold water hole. It has a depth of 2,5 km. This means that magma is at or close to that depth. Ground water in this area doesn’t go deeper than 1,9 to 3 km I think (I am not sure on how the fresh water ground level works in this area).
  • Eruption is expected from hours to day based on most recent measurements from Icelandic Met Office.
  • Grindavík town continues to sink according to news today (16. November 2023). Difference between days can be as much as 25 cm.
  • Mbl.is (Morgunblaðið) has a video of the damage done by this sinking on their website here. Its in Icelandic.

The situation for now is quiet, but that might only last for few hours to days longer before an eruption starts. Since earthquake activity strongly suggests that magma is looking for a way to the surface. While some magma is at shallow depth of 400 to 500 meters. There’s not enough of it to start an eruption. That can change without any warning at any time in this situation.

I’ll write updates if anything more happens here as quickly as I can.

Update on Grindavík 15. November 2023

This is a short update on what is happening in Grindavík on 15. November 2023. Information here might go outdated quickly.

In general, not much has changed since yesterday (14. November 2023).

  • There’s no change in earthquake activity. Strong wind in the Reykjanes peninsula might be masking some of the smaller earthquakes.
  • Part of the harbour area has started to sink according to news. I am not sure how much, but I think it might be considerable sink.
  • Speed of the sink in some areas of areas inside Grindavík has increased from 7 cm for each 24 hours to 12 cm for each 24 hours since yesterday. Some areas inside Grindavík have lowered as much as 2 meters or more.
  • Inflow of magma into the dyke continues to be at 75 m3/second according to news reports today. This is a lot of magma inflow into the dyke. The eruption in Holuhraun in 2014 and 2015 had an flow of 90 m3/sec when it was the most.
  • It is reported on mbl.is that it is now considered that magma might be flowing directly from the main magma chamber at 20 km to 40 km depth under this location in Reykjanes peninsula. That news is in Icelandic here.
  • Parts of Grindavík town has lost power, hot and cold water because of sinking of the ground and movements. Emergency repair is going to be attempted tomorrow if it is safe.
  • Eruption might happen at Sundhnúkar and Hagafell, where the highest flow of magma is happening according to Icelandic Met Office and the news.
  • Eruption at many craters at the same time is what is going happen here. Based on what I am seeing. That means more lava covering larger area quicker than the small eruptions in Geldingadalir, Meradalir and at Litli-Hrútur. Where it was just one crater and a small eruption.
  • Something is holding back the magma from reaching the surface. What that is unclear. But magma is at shallow 500 meters or less according to measurements done by Icelandic Met Office. This shallow depth means that magma can start erupting without much warning or notice in the dyke.

There is a chance that parts of Grindavík town might sink under the ocean because of the ground sinking. When eruption starts, what goes under lava depends on where the eruption is going to start and where the lava is going to flow. Both are random events that is impossible to know anything about.

If anything happens. I’ll post update soon as I can. If anything happens tomorrow I’ll write about it. Otherwise I plan on publishing next article on Friday 17. November 2023. Since changes at the moment are not that big changes between days currently.

Update on Grindavík on 14. November 2023

This is a short update on the situation in Grindavík and nearby area. Information here can go outdated quickly and without warning.

For the press media. Please contact Icelandic Met Office or Department of Civil Protection and Emergency Management for any important information or interviews. I already write everything I know here on this website as needed. Thanks.

  • The magma is at 400 meters depth, where it is at its most shallow.  I am not sure on location, but I think it is just north-east of Grindavík town.
  • There is strong wind on Reykjanes peninsula. That normally hides some of the smaller earthquakes happening. Icelandic Met Office continues to record 700 to 3000 earthquakes each day. Most of them are along the dyke and most of them are in the magnitude range of Mw0,0 to Mw3,1. With the stronger ones happening least often.
  • Inflow of the magma into the dyke is at the writing of this article around 73 m3/s to 75 m3/s. On Friday 10. November that inflow was 1000 m3/s.
  • Sulfur dioxide was detected today north of Grindavík. That suggests that magma might be at shallow depth in the dyke area.
  • News reports today did say that the area in Grindavík and nearby continues to sink around 7 cm over 24 hour time period. This might be uneven process depending on the area.
  • Lakes south of Grindavík have been seen growing, as the area continues to sink and get lower. It is a question of parts of this area is going to get flooded by the ocean soon. This is reported on Facebook by Eldfjalla- og náttúruvárhópur Suðurlands.
  • The GPS station just north of Grindavík has lowered by 1400mm since Friday 10. November 2023. The stations on the east are going up, some much as 1 meter. While the GPS stations on the west side are lowering.
Line of red dots shows all the small earthquakes, along with one green star on it. This show all the 15 km of the dyke.
The dyke as it appears on the earthquake map. Copyright of this image belongs to Icelandic Met Office.

This situation changes quickly and often from hour to hour. I’ll post new updates if something major happens, quickly as I can.

Article updated on 15. November 2023 at 00:21 UTC. – Removed information that might not be correct.

Update on the situation in Grindavík on 13. November 2023

This is a short update. Information here can go outdated quickly and without warning. I am sorry for the Google Adsense popup ads. They turned them on without telling me and I can’t turn it off. I never run this type of ads because this is just annoying pop-up and I don’t allow that on my website. Google Adsense ads are going to be gone by the end of this month anyway (regardless of anything else).

The situation is similar to yesterday. Earthquake activity continues to drop for now. But that might be a short quiet because the dyke and the rift valley continues to grow. Inflow of the magma continues, at slightly slower rate than on Friday 10. November 2023.

  • The inflow of magma on Friday 10. November 2023 was 1000 cubic meters per second according to Icelandic Met Office and experts.
  • The rift zone that is lowering is on the western side of the Grindavík town. The east side is rising up to almost the same amount. Parts of Grindavík have lowered around 1 to 2 meters. Some of the cracks in the grounds are up to 20 meters deep or deeper.
  • There is a lot of damage in Grindavík to many houses. If not from earthquakes, then from the formation of the rift valley.
  • Eruption risk remains high and the dyke seems to holds its length at 15 km. This can change without warning.
  • The rift valley is now around 2 km wide according to the news. The rift valley continues to get wider according to measurements.
  • There has not been any drop in harmonic tremor on SIL stations next to the dyke, even if earthquake activity has lowered. This is because of the ongoing inflow of magma into the dyke.
A line of red dots shows the dyke formation that goes under Grindavík town and goes north-east of the town.
The earthquake activity in the dyke appears clearly. Copyright of this image belongs to Icelandic Met Office.

It is not possible to know what happens next. It is my view that an eruption is going to start in this area. This is a start of a activity that is going to last for a while until it quiets down.

This dyke activity might also upset the volcanoes Fagradalsfjall and Reykjanes and what is happening in them. Anything can happen in them without warning. If not eruption, then earthquake activity.

I’ll post update when I have some new information about this situation.