Fewer earthquakes close to Keilir, no eruption in Fagradalsfjall mountain for almost one month

Earthquake activity continues close to Keilir mountain. But it remains at depth of 5 to 6 km and doesn’t show any sign that it is about to move to the surface. More than 10000 earthquakes have been recorded and 18 earthquakes have been recorded with magnitude above Mw3,0. This is according to Icelandic Met Office.

Earthquake activity close to mountain Keilir marked by a green star close to it of the map on Reykjanes peninsula
Earthquake activity close to Keilir mountain on Reykjanes peninsula. Copyright of this image belongs to Icelandic Met Office.

The eruption in Fagradalsfjall mountain (more information at Krýsuvík-Trölladyngja website at Global Volcanism Program) has not been active since 19-September-2021 and there are no signs that the eruption is about to restart soon. Global Volcanism Program no longer updates its information for this volcano as an active eruption. Icelandic scientists in eruptions have not declared the eruption over. It should be expected that the eruption in Fagradalsfjall mountain is over for now, but it can start again at the same location or at new location in few weeks time or maybe even few years from now.

Ongoing earthquake swarm close to Keilir mountain

The earthquake swarm with Keilir mountain continues today (2-October-2021) and largest earthquake at the writing of this article had a magnitude of Mw4,2. This might change without warning.

Green stars on Reykjanes peninsula close to the mountain Keilir. Shows where the current activity is.
The earthquake activity close to Keilir mountain. Copyright of this image belongs to Icelandic Met Office.

Based on what I am seeing it is my view that magma is the reason why this earthquake activity is happening. The magma seems trapped, based on the earthquake activity and that is interesting. This suggest that the feeder channel, that possibly started at this location has closed up and that is the reason why the eruption in Fagradalsfjall mountain stopped. At least that is the working idea, if it is true I don’t know.

Department of Civil Protection and Emergency Management and Icelandic Met Office has warned people against going to Keilir mountain because of risk of volcano eruption or large earthquakes.

It is unclear at the writing of this article if there are changes to hydrothermal activity close to Keilir mountain. There have been reports about it, but they remain unconfirmed at the writing of this article.

There is now a risk of an earthquake with magnitude of Mw6,0 in the area of Keilir mountain. The earthquake activity shows a pattern of high and low activity every few hours. Why this happens is not well understood at the writing of this article.

Earthquake activity south of Keilir mountain

On Saturday 25-September-2021 an earthquake swarm started close to Keilir mountain, at the writing of this article this earthquake swarm is ongoing.

Red dots on Reykjanes peninsula show the location of an ongoing earthquake swarm that is now happening.
Earthquake swarm on the Reykjanes peninsula. Copyright of this image belongs to Icelandic Met Office.

The eruption in Fagradalsfjall mountain has been having its longest quiet period since 19-March-2021 and at the writing of this article that is ongoing situation.

This earthquake activity suggest that the eruption time period in this part of the Reykjanes peninsula is not over, even if nothing is happening at the moment.

Krýsuvík-Trölladyngja is a volcano system is currently erupting in this area.

Article updated on 29-September-2021 at 11:49 UTC. Correct date of the earthquake swarm start added to the article.

Unconfirmed activity in the area of Keilir in Fagradalsfjall mountain eruption

This is unconfirmed so there might be number of other reasons why this is being observed. This also might be wrong reporting but based on web cameras that might not be the case. There has been some visual view of this on web cameras. Here are two pictures that I was able to screen grab from two of those cameras.

Thermal black and white image showing a bright spot on the centre of the image suggesting a strong heat source.
There is a heat source in this image. Where it is located is currently unclear. Copyright of this image belongs to Míla and Securitas.
Black image showing two light dots. With the dot on the left being a car or some human made noise. While the dot on the right might be a small eruption that is unconfirmed.
The light on the right of this image might be the an unconfirmed eruption. Copyright of this image belongs to Míla.

It is unclear what is going on and this might all be wrong. But I am also seeing this new light source on the web camera from mbl.is on YouTube as it peaks a little from behind the large crater in Fagradalsfjall mountain. That crater is not active at the moment.

I don’t know when confirmation is going to appear. If this is an eruption. If this is not an eruption, then there is going to be a confirmation of that too. I’ll post update here is I learn anything more in the next few hours.

Update 03:07 UTC 7-September-2021

The light on the second picture (on the right) is a human made light. I think it is the lighthouse. What is appearing on the thermal camera has not been identified.

Update 13:36 UTC 7-September-2021

This is wrong reporting that happened here. Nothing happened and what was seen on the thermal camera is most likely the heat from the crater. This type of wrong information happens every once in a while. Currently the main crater remains inactive and sulphur colours have started to appear on him from the sulphur outgassing that is now happening.

Article updated at 03:08 UTC on 7-September-2021

Article update at 13:39 UTC on 7-September-2021

Update on the eruption in Fagradalsfjall mountain on 21-May-2021

This is a short update on the eruption in Fagradalsfjall mountain on 21-May-2021. This is part of the Krýsuvík-Trölladyngja volcano system.

There has not been a lot of change since last update on the eruption. The eruption has now been going on for two months and few more days. There are no signs of the eruption ending.

  • The lava fountain activity continues as it has been doing for the last month.
  • Output of lava has been increasing and is now around 11m3 compared to 5m3 at the start of the eruption.
  • Lava is now on its way to the ocean by flowing down into Nátthagadalur valley. There is an attempt to try and stop or delay that from happening by pushing up defences and try to hold back the lava field. It is my personal view that this attempt is going to fail, at most it is only going to delay the lava a little bit. Since the lava field also has to get over a hill that is in its path anyway. That is only going to take few days to a week depending on how much lava is being fed into this part of the lava field. That changes all the time with no warning.
  • Most of the lava goes into Meradalir valley where it is for now not putting anything in danger or risking infrastructure.
  • SO2 pollution is starting to show in south Iceland. There was also report of static electric charge build up around the eruption site yesterday (20-May-2021). It didn’t result in a lightning but the risk was in place for a good while.

There are for now no other news of the eruption and it has been quiet in other parts of the Iceland during the last week.

Update on the eruption in Fagradalsfjall mountain on 15-May-2021

This is a short update on the eruption in Fagradalsfjall mountain. This eruption is part of the volcano system Krýsuvík-Trölladyngja volcano system.

The eruption continues as before but increase in lava output has been detected and is now 70% more according to latest news from Icelandic Met Office and Earth science of University of Iceland. Compared to the start of the eruption on 19-March-2021.

  • The eruption continues in one main crater. It erupts in lava fountain style at the writing of this article. With highest lava fountains reaching the height of 400 to 500 meters. The lava fountains can be seen from Reykjavík and other nearby area.
  • The lava field is about to reach Nátthagi valley and there is now an attempt to stop that from happening. Because of nearby road and fibre optic cable that runs through that area. It is my estimate that attempts to stop the lava flow are going to fail when the lava flow starts going back to Nátthagi valley.
  • The main crater is now 50 to 90 meters high. But his height is always changing because of continued collapse from it inside it and outside it. The process of collapse is slowly growing the crater volume and size.
  • The magma seems to be coming from even deeper part of the mantle compared to with start of the eruption. Based on lava changes in the chemical makeup.
  • There are no signs of the eruption about to be ending soon.

It is difficult to know for sure what happens next in the eruption. Opening up of new craters outside of current line of craters is something that might happen. With the eruption growing in size it is difficult to know for sure what is going to happen next in Fagradalsfjall mountain.

Update on the eruption in Fagradalsfjall mountain on 30-April-2021

This is a short update on the eruption in Fagradalsfjall mountain on 30-April-2021.

There has not been any major changes since last update. This are the noticeable changes since last update in the eruption in Krýsuvík-Trölladyngja volcano system.

  • Just one crater is now erupting. All other craters have stopped erupting but for now some of them might contain lava lake for now that might be creating a flow in lava tubes under the surface in the lava field. This process might not be visible on the surface.
  • A lot of activity now is in form of high lava arcs (correct word?) are now being formed in the one crater because of increased gas content of the lava.
  • Lava fields are slowly filling up all nearby valleys that it is flowing into. This is a slow process and is going to take months.
  • There are no signs the eruption is about to end.

No other updates have been reported so far. Rúv has installed a new web camera to give better view of the eruption. That camera can be found on YouTube Rúv channel.

Vacation

I am going on a small vacation between 5th May and 10th May. That means next update about the eruption is going to be on 14th May. I don’t know if I can go to the eruption yet as that depends on the weather and the weather is always unstable in Iceland.

Earthquake activity south of Keilir mountain

During the night of 27-April-2021 an earthquake swarm took place south of Keilir mountain in Krýsuvík-Trölladyngja volcano system. This earthquake activity at this location has been going on for a long time and is interesting. There are no sign that suggest an eruption is about to happen at this location, that is the situation at the writing of this article. Largest earthquake in this swarm had a magnitude of Mw3,2 at the depth of 6,1 km and second largest earthquake had a magnitude of Mw2,8 at the depth of 5,9 km.

Earthquake activity south of Keilir mountain shown by a green star on the map of Reykjanes peninusla
Earthquake activity on the Reykjanes peninsula. Copyright of this image belongs to Icelandic Met Office.

It seems that there is a chance there might be changes about to happen in the eruption in Fagradalsfjall mountain. I am going to write about that tomorrow at the earliest, but the article might be delayed of there is a lot going on while I gather information about what is happening.

Update on the eruption in Fagradalsfjall mountain on 26-April-2021

This is a short update on the eruption in Fagradalsfjall mountain in Krýsuvík-Trölladyngja volcano system.

There are no major changes reported during the last few days. But there have been minor changes in last few days. Here the latest changes that have been reported.

  • The oldest craters have stopped erupting. One of the crater has changed into a lava lake for now while the other is possible also a lava lake even if it is not visible. A lot of gas (smoke) comes from the more south crater in the crater row 1.
  • There are three to four craters that continue to erupt. There seems to have been a tiny increase in the eruption today (26-April-2021). This can be explained by how few craters are currently erupting.
  • No new craters have opened up in last few days. This is correct at the writing of this article.
  • Harmonic tremor seems to be decreasing. It is unclear why that is since the eruption is currently ongoing.

There are no other reports about the eruption. I am not sure when next update is going to happen but it is going to be soon as possible if anything changes in the eruption.