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.

Update on the eruption in Fagradalsfjall mountain on 16-April-2021

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

There has not been any major change since last update. In this week four new craters started erupting and I write an article about that earlier in this week for more details.

  • It was reported today (16-April-2021) that lava has now started to flow outside of Geldingadalir and to the east. This lava is now flowing over a walking path that people used to get close to the eruption. Getting close to the eruption might not be possible any more. There is also a chance that lava is going to is going to flow to the south of the craters more than it already has done.
  • Swarm of small earthquakes took place north-east in Fagradalsfjall mountain early morning around 06:00 UTC. Largest of those earthquakes had a magnitude of Mw2,8.
  • There is no sign of the eruption ending.
  • There continues to be a high risk of new vents opening up and start erupting without warning.

There are no more reports this week outside of what I did write about what was happening earlier in the week. If anything major happens I am going to post an update soon as possible.

Stronger harmonic tremor reported in Fagradalsfjall mountain eruption

Yesterday (15-April-2021) it was reported (late) that harmonic tremor seems to have been increasing in the eruption since midnight. This normally happens if new craters have opened up. The weather is really bad at the eruption site currently so viewing the eruption with any web camera is difficult if not impossible. Rúv web cameras failed last night because of the weather that has been seeing wind peaks up to 41 meter/second with heavy rain. Current weather forecast is that the weather is not going to start improving until late today (Friday 16-April-2021). The increased tremor might be weather but weather is in general easy to filter out and doesn’t affect the lower bands (0.5 – 1Hz) that much as it does higher bands (2 – 4hz). What is happening won’t be clear until the weather starts getting better.

Information about the volcano Krýsuvík.

News and web cameras that might work

Órói auk­ist en aðstæður óljós­ar (mbl.is, Icelandic)
Gosið í Geld­inga­döl­um í beinni (web camera, mbl.is) – The fog cover sometimes breaks a little on this web camera.

Currently total of eight craters are erupting in Fagradalsfjall mountain

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

Yesterday (13-April-2021) the following thing happened around 09:00 UTC.

  • Four new crater started erupting. This did not reduce the lava output of the other craters that are erupting.
  • This means that now are total of eight craters erupting in the eruption in Fagradalsfjall mountain. The area is slowly being buried by fresh lava as the eruption goes on.
  • On Sunday 18-April-2021 it is going to be 1 month (30 days*) since the eruption in Fagradalsfjall mountain started. *This is a calendar thing, but using a website to calculate this correctly then this is the correct day using 30 day month calendar.
  • There continues to be high risk of new eruption fissures opening up without warning. Both north and south of the crater 1.
  • Gas output from the eruption has more than doubled in last few days. This is starting to create problem if wind blow the gas over populated areas.

I don’t have any more updates as is. If anything more happens I’ll update soon as I can. Since there is a risk of this eruption is going to last for a real long time, up to several years I might change my update schedule from what it is now. I’ll figure that out as the eruption continues.

News of the new craters

Drónamyndir: Fjórir nýir gígar (Rúv.is, video, map of the new craters)

Update 18:24 UTC

Morgunblaðið has released new video of the eruption craters.

Flögrað yfir nýju gíg­un­um (mbl.is)

Article updated at 18:25 UTC.

Update on Fagradalsfjall mountain eruption on 9-April-2021

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

This week has been busy and please read the older articles about what happened earlier in this week.

  • Lava output is now 50% more according to University of Iceland measurements compared to start of the eruption (19-March-2021). Gas output is also more then in start of the eruption. It has resulted in problems depending on wind direction.
  • There is a high risk that an eruption might start south of Geldingadalir valley eruption. There is also a high risk that new eruption is going to start north of the 5-April-2021 eruption.
  • There is no change in inflation in the area. It has slowed down but remains the same.
  • There continues to be low level earthquake activity along the dyke from Keili to Fagradalsfjall mountain.

Any change that is going to happen without warning and might not happen without any earthquake or little earthquake activity.

Next update is going to be on 16-April-2021 unless something major happens. This eruption is always changing and this weekend and next week might get interesting. If anything happens I am going to write new article soon as possible.

Update at 22:43 UTC

Icelandic Met Office released this map and press release (in Icelandic only) about the risk new fissures can open up both north and south the the current craters that are erupting. This page is updated regularly so if you are looking at this later than 9 to 10 April 2021 you might have to look for this information.

Map showing marked area that goes little south and north of the current erupting fissures in Fagradalsfjall. That area has been marked as dangerous by Icelandic Met Office. The map also shows the lava fields in purple.
The new area that has a risk of new fissures opening up without warning. Copyright of this image belongs to Icelandic Met Office.

The map shows the area that is now at risk of new fissures opening up without warning.

Update 10-April-2021 at 15:20 UTC

Around 03:14 UTC on 10-April-2021 fissure number 4 did open up between fissure number 2 (5-April-2021) and fissure number 3. The eruption from this crater doesn’t seem to be large but it did happen under a new lava that had flowed over that same area few days before from fissure 2. In fissure/crater 1 the amount of erupting lava did drop a little just before the new eruption.

I am noticing that it seems new fissures are opening up more frequently then before. This seems to have changed after opening up of fissure 3.

Timeline of fissure openings so far.

1st fissure 19-March-2021
2nd fissure opened 5-April-2021
3rd fissure opened 7-April-2021
4th fissure opened 10-April-2021

Time period between new fissures opening up currently seems to be 3 to 4 days. I suspect that this is going to change soon and it is possible that new fissure that opens up might get larger as the eruption goes on. There seems to be phase in this eruption that is happening in Fagradalsfjall mountain. I am not perfectly sure what that phase is now since I’ve never seen this before and I don’t have any data on this type of eruption behaviour from other volcanoes outside of Iceland. That I know of.

Video of the eruption fissure 4 opening up.

Nátt­úr­an er óút­reikn­an­leg og ófyr­ir­sjá­an­leg (mbl.is)


Article updated at 22:48 UTC.

Article updated at 15:39 UTC on 10-April-2021.
Article updated at 15:54 UTC on 10-April-2021.

Update on Fagradalsfjall mountain eruption on 8-April-2021

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

Last 24 hours have been busy in the eruption. Here are highlights of what has happened best to my knowledge.

  • New fissure opened up and started erupting between the Geldingadalir eruption, second day of Easter eruption and the new eruption fissure is between the two.
  • The lava fields have now merged and are now one large lava field from Geldingadalir down to Meradalir valleys.
  • The eruption continues at the same slow rate as before even with several new vents erupting.
  • Morgunblaðið lost their first web camera to the lava flow (news can be found here in Icelandic). Icelandic Met Office had hardware close to the new lava flow. I don’t know if that hardware was saved from the lava flow but it was planned attempt to do so before it was lost to the lava.
  • The fissures might merge at future point and start erupting at one large fissure eruption. It is impossible to know if that is going to happen or when that might happen.
  • There has not been any deflation detected in the GPS data after the eruption started. That GPS data can be viewed here.
  • New fissures have been detected north of the crater that started erupting on 5-April-2021. Those fissure might start erupting without warning.
  • There is a risk of the eruption also going south-west and opening up fissures there. That has not yet happened but the possibility remains as a high risk possibility.

The situation is difficult to predict and new fissures can open up without warning. If nothing major happens then next update is going to be Friday 9-April-2021 on the eruption.