Update on the Fagradalsfjall mountain eruption on 12-September-2021

This is a late and short update on the eruption in Fagradalsfjall mountain on 12-September-2021. Fagradalsfjall mountain is part of Krýsuvík-Trölladyngja volcano system.

Yesterday (11-September-2021) at around 05:00 the harmonic tremor on SIL stations around Fagradalsfjall mountain started to show an increase in harmonic tremor after a break of 8 days. It took few hours for the magma to reach the crater and lava was visible in the crater around 12:00 UTC.

Harmonic tremor chart in purple (lowest frequency), green (mid range frequency) and blue (highest frequency) that shows in the increasing harmonic tremor by rising at the end of the link up to 6000 units (not defined) at 00:38 Icelandic time.
Increasing harmonic tremor at 00:38 UTC on Fagradalsfjall mountain SIL station. Copyright of this image belongs to Icelandic Met Office.

There have been possible new vents been opening up yesterday and today in the lava field. Icelandic Met Office says that this is a lava flow under the old colder lava and is now breaking up and looking like new vents. I don’t know yet if this is accurate, but it is my early assessment that this are new vents and are going to build new crater, at least there is a possibly of crater building if the new vents stay active long enough.

If this are new craters as I suspect, then they are going to change the lava flow quickly and increase the output of the lava flow from what it was. It might soon start to flow down into Nátthagi and other locations that are nearby.

It is a big question if the cycle eruption with no activity for hours has stopped for now. If this has turned back into an eruption that goes in 24 hours a day, that is going to allow the lava field to reach a lot more distance then before.

Update on the eruption in Fagradalsfjall mountain on 10-August-2021

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

  • The eruption continues as before with few hours of eruption and few hours of no activity. (This is my personal view of the situation) Each event is an active eruption as it would happen with any other volcano. The time between eruptions now is just shorter than in any volcano in Iceland. Its hours, not decades between eruption. I don’t know why this is happening like this.
  • Cracks have appeared in the viewing area hill closest to the erupting crater. Why this is happening is unclear. There are two explanations for this. The first one is that this are tension cracks because of the eruption and lava flows nearby to this hill . The second explanation is that this is deformation cracks because magma is about to start erupting in this part of the hill. Formation of new cracks was observed early on in the eruption in Fagradalsfjall mountain few days before an eruption started in that area.
  • There is now slightly less lava flowing from the crater. Current flow is up to 9m3/sec according to latest reports about the lava flow. This studies are done by Earth Science of University of Iceland and Icelandic Metrology Office.

This eruption remains small. Currently it is even smaller than Hekla volcano 2000 eruption that was the smallest eruption in Hekla in recorded history (according to the news). While the eruption remains this small the lava is not going to flow far or is going to do so slowly. Most of the lava is just going to build up next to the crater and next nearby area.

People continue to walk out in the lava and that is extremely dangerous. The lava field, where it is deep enough has large caves full of 1100C hot lava and if the roof breaks and people fall into it there is no saving anyone from this. Just break in the lava field crust allows for lava flows to break out with same deadly consequences.

Update on the eruption in Fagradalsfjall mountain on 11-June-2021

This is not going to be a long update since there has not been a lot of change during the last week. There has been some and this is what happened. This is part of Krýsuvík-Trölladyngja volcano system (until the studies are updated).

  • The main crater is slowly closing and lava fountain activity has almost or has ended at the writing of this article.
  • The main crater is now around 100 meters high. Lava depth is from 10 to 70 meters thick depending on a location. There is a map but for copyright reasons I can’t show it here.
  • Lava flow is now permanent and does not happen between overflows necessary.
  • Lava lake might be forming in the crater, but the status of that remains unclear at the writing of this article.
  • There are overflows happening in the crater but according to the news the main lava flow happens underground in large dykes that go from the main crater into the lava field. Creating lava ponds that regularly break and expand the lava field at random.
  • Today (11-June-2021) people that are idiots where seen walking on the fresh lava that has a surface temperature from 50C to 100C in order to get to the viewing area (blocked by fresh lava flows) and one did even go as far walking on the slopes of the crater and almost ending up as part of the lava field him self. Video of that can be seen here on mbl.is website. As can be seen the lava flows them self are human height and can bury a person in a few seconds time.
  • Fresh lava in Fagradalsfjall is hot. While it is only 100C on the surface it can be 900C just few centimetres down and can go as high as 1100C if a surface of a lava tube is broken.
  • Yesterday (10-June-2021) a change happened in the eruption and that resulted in a change in the harmonic tremor that continues. Suggesting a permanent or a long term change to the eruption. What this mean is unclear currently.

There are no other updates as is. Next update should be on 18-June-2021 unless something happens in this eruption. Other parts of Iceland are quiet at the writing of this article.

Blue, green and purple show the harmonic tremor from the eruption in Fagradalsfjall. The change on 10-June shows a sharp edged harmonic tremor plot.
The harmonic tremor on nearby SIL station to the eruption in Fagradalsfjall mountain. Copyright of this image belongs to Icelandic Met Office.

Donations

Please remember to support my work with donations. Currently most of my work is trying to monitor the eruption in Fagradalsfjall mountain. Thanks for the support. 🙂

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.

Update on the eruption in Fagradalsfjalli mountain on 23-April-2021

This is a short update on the eruption in Fagradalsfjall mountain on 23-April-2021 for the last week. Information is provided with best effort. The volcano that is erupting is Krýsuvík-Trölladyngja volcano system.

No major changes have been seen this week in the eruption. Here are the highlights.

  • According to last chemical analyse of the lava. The magma that is coming up is getting more primitive and from deeper part of the mantle. This increased the chance that the eruption is going to go on for months to years. Details can be found here on Twitter or here on Facebook.
  • Thickness of the lava is in most places just 16 meters. In Geldingadalur valley the thickness is at most 50 meters and getting thicker as the eruption continues and the valley slowly fills up. The lava doesn’t flow far and so it piles up next to the erupting craters.
  • At the writing of this article it seems that crater 1 is slowing down or shutting down. There seems to be some activity but it is low and mostly just gas is blowing out.
  • Craters continue to collapse as the eruption goes on. This happens at random and results in flood of lava happening.
  • The most active area now is the craters that opened on 7th of April and other time after that.

Other than this the eruption continues to be stable and the flow of lava is around 5m2/second according to last report I did read in the news.

Update on the eruption in Fagradalsfjall mountain on 19-April-2021

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

  • The crater that started erupting on 5-April-2021 has stopped erupting. I am unclear when it stopped erupting but that must have happened sometimes in last few days.
  • Smaller vents have opened up but none of them have been able to create any major eruption crater. Most of those have also stopped erupting and been buried by fresh lava from others craters when they stopped erupting.
  • Earthquake activity has been appearing along the dyke in last few hours. I am unclear what that means at the writing of this article.
  • New fissures with steam or hot air have been reported south of current eruption. I am unclear where they are located. There don’t appear to be any new fissures north of the crater that has stopped erupting at the writing of this article.
  • Crater 1 has now started to smoke a lot. While the second vent continues to erupt a smaller eruption. I am unclear on why one of the vent is smoking as it has been doing for the last few days.
  • The eruption is now 1 month old today. The eruption started on 19-March-2021.
  • Amount of lava being erupted has increased since the start of the eruption according to latest reports.

I don’t have any more reports today but that might change without warning. If that happens. I am going to write an article soon as I can.