Fagradalsfjall, Season 3

/ 10/07/2023

Eruption

It is hard to remember what Iceland was like three years ago. At that time, most (or all) eruptions were in the eastern volcanic zone, from Katla (and friends) to Krafla. (Ok, one can argue about the precise borders. Grimsvotn was about to erupt. The Thorbjorn swarm had happened and an eruption at Reykjanes was seen as possible, but the peninsula had been quiet for 800 years. This was when we postponed the eruption to 2021 due to covid (cue: April 1). Iceland followed our lead and indeed in early 2021, after an impressive series of earthquakes on the Reykjanes fault, an eruption followed in the most unlikely location: Geldingadalir, a remote valley within Fagradagsfjall, where no eruptions had occurred for perhaps 30,000 years. Who would have guessed? Since that time, there have been three eruptions in three years. And we are still waiting for Grimsvotn.

The first Fagradalsfjall eruption was perfect tourism. It was in a location where no one was endangered, while still easy to reach for the watchers. This being Iceland, webcams were put up in various locations, maintained by the locals and watched around the world. Of course, this being Iceland, the locals use the cameras to display themselves and even slogans were put on view, sometimes to the watcher’s entertainment and sometimes to their annoyance. But when entertainment is provided for free, it is hard to begrudge the occasional advert! The eruption evolved through fissures, effusive cones, tall fountains visible from Reykjavik (lucky things) an finally sputtering. We learned that Icelandic eruptions can be controlled. A wall was build to deflect the lava, and indeed the lava was deflected. The same was attempted at the place where the lava began the threaten the road and farms, and immediately the eruption ended.

A group of people standing in front of a volcano Description automatically generated

The power of Iceland was obvious in many ways. As Reykjanes sputtered into action. Etna was delivering unbelievable fountains, tall enough to keep even Jesper happy (perhaps not Tallis). But it stood no chance. The eyes of the world were drawn north.

A group of people walking down a street Description automatically generated

It ended after some 6 months. By that time the original valley of the eruption no longer existed, and neither did the deeper valley next door nor the hill were the first lava emerged . Iceland was left with new geography and a new hill which still has a warm conduit, and we were left with happy memories.

A year later came a new eruption, an afterthought of the first. We had kind of expected that the Earth was not finished here and that at some time the magma would break through again. It happened in the northern part of the original eruption. The eruption was much less vigorous, and season II was a pleasant sight but not on par with season I. The lava field expanded a little but that was it.

For the start of Season 2, see
https://drive.google.com/file/d/1PKzvTGMTr_Iln5VijqOosRj_SiyYNQlX/view

But intrusions continued, last winter and in the spring. As before, a dike sprung up and expanded in a NNE-SSW direction. The location of the deeper magma source is not so easy to determine. The first intrusion had been further west. This being a zone with a bit of extension, there is a region some 5 kilometer wide below which magma can collect. From there, dikes can grow. Some are very deep, tens of kilometers. This go north, and can continue for 50 kilometers or more but they never reach the surface. More common are shallower dikes at 5-7 kilometers which do not go very far but quickly move up. The current intrusion was focussed further north than might be expected, with the upward growth southeast of Keilir. But it is not clear where the magma originally came from. The earthquakes and insar showed that the dike extended between Keilir and Litli Hritur, just north of Fagradalfjall.

insar

A map of a mountain

The eruption started today at the bottom slope of Litli Hrutur, with a 900-meter fissure extending about half the distance to Keilir. As I am writing this, the lava is beginning to flow around the hill but it is not clear to me in which direction! And sadly, the eruption is too close to the cameras for a good view! I am sure that will be fixed. This is Iceland, after all. They will try to move the eruption.

What will happen next? The eruption had a sluggish start, surprising perhaps after the vigorous dike formation. But this was also the case in Season 1, and in any case the volume seems to have increased a lot as the fissure lengthened. This could develop in an event similar to series 1, lasting several months and covering a large area but well away from roads and houses. It could also be a rerun of Season 2, lasting a few weeks. The former seems more likely given the intrusion, but this is not certain.

Viewing will be harder than for Season 1, being further away from the road and requiring a longer walk. But I am sure that the coffee van will be appearing shortly at the parking area, ready for the thirsty tourists. We are in for a treat.

Location of the dike. Initial lava flow shown in blue

Albert, July 2023

And here is a reflection by Randall, taken from the comments

My own personal observations of events leading up to the fissure eruption.

  1. The website https://vafri.is/quake/#close posting quakes proved invaluable this time for knowing how events were progressing. I watched the screen literally hours and began to discern patterns. Once there was like a surge and small quakes burst out over in the Krisuvik area and you could follow this surge by watching for about 1/2 hour or so. I took this to mean a magma surge. The constant activity to the NE showed that pressure was high.

  2. A key comment made by Tomas Andersson about triggered quakes related to the inSar butterfly picture helped me to understand the quakes occurring on the vafri.is/quake website for the past 3 days.

  3. The FAF seisometer was a good source of watching the microquakes, and I am sure that at least 3 episodes (barefuly distinguishable) of microtremors occurred. The time from 14:50 pm to 18:00 pm today (2023-July-10) on the seismo shows a slightly thicker trace. This seems to indicate that actually watching microtremors is a very difficult science even today and fissure eruptions are still hard to accurately predict

  4. The strong 5.22 quake yesterday had few aftershocks, indicating (my terms) mushy ground or softened up ground by magmatic intrusion. This in hindsight was an indicator of closeness to the actual eruption.

  5. There appears to have been a small microquake around 16:38 pm which slightly shook the RUV cameras on Litli-Hrutar, and I take this as the final breakthrough of the fissure. IMO dated the eruption at 16:40 and the RUV north camera showed the first smoke at 16:41:07 pm. It is really hard to catch fissure eruptions as they first begin.

  6. The two flights of small birds that I saw around midnight Iceland time were interesting. Birds seem to have a foreknowledge of events, and their flight path was directly away from the region at about right angles to it (giving them the maximum distance via minimal flight time) Before the Hebgen Montana 7.3 quake of Monday August 17, 1959, the water fowl left Hebgen Lake about 2 pm in the afternoon and their absence was noted in the sheriff’s log at West Yellowstone. The quake that evening gave the reason why the waterfowl left. They came back to the lake after the 3rd aftershock on Wednesday Aug 19th or so. My dad took our family to this epicenter about 2 or 3 days later and we saw the lake filling up, and all the damage and trees disappearing into the water and it left an indelible impression upon me as an 8 year old.

  7. Scientifically things have improved, we’re in a better knowledable condition that when the 1st eruption started back in 2021.

  8. The hot water pouring from the borehole in Avedir (spelling) was definitely a sign of nearness of the eruption, but it was 11 km from Keilir. That is a wide area for a thermal pulse to travel. Do we know much about how much thermal energy is spread when a dike intrudes? More studies of borehole water and temps needs to be done.

  9. Several people on Volcano Cafe gave fairly accurate predictions of the location of the fissure eruption, I believe Albert might have been the first to speak up. Chad gave one as did Alice, but there were others and I apologize for not mentioning you.

Finally the excitement leading up to a fissure eruption is almost addictive. It really is fun watching a volcanic event like this occur, especially when it is fissure eruptions which have not occurred for some 800 years.

These are some thoughts as I reflect back through events leading up to the fissure eruption today.

And a response to these: the hot water can easily flow 11 kilometers, so it may well have come from the region around Keilir. The underground rock insulates well but underground water can circulate and transfer heat very effectively when coming close to the magma. Gas emissions can also heat up the region. As to the birds, this was commented on below. It seems unlikely they predict eruptions, and in fact I recall tropic birds flying very close to the eruptions at Kilauea. They may be affected by earthquakes, of course, and perhaps by the SO2 emissions that can precede an eruption – Albert

Related posts

589 thoughts on “Fagradalsfjall, Season 3”

  2. Acme is carrying three excellent camera angles. Just read a report that the police have shut down access to the site indefinitely. No further explanation on that. From the videos it appears that activity has ramped up.
    https://eruption.acme.to/

  3. Mayon’s eruption is still going and it looks like lava effusion is intensifying slightly, and the longer this goes, the more unstable the lava dome becomes.
    CCN is going to drive me nuts! Gotta write another article about this years swarm and I am currently wondering if seismic uptick over the last couple days is the start of a new swarm or the continuation of the old swarm! Can I get an official explanation on what is causing these swarms? Because there hasn’t been any since 2020. The IGEPN hasn’t released a monthly report in a over a year. Facts, data, explanations, things I kind of need right now!

    • AVO has finally shot a photo of the new Strombolian eruption at Shishaldin:

      “Shishaldin is one of the most active volcanoes in the Aleutian volcanic arc, with at least 54 episodes of unrest including over 26 confirmed eruptions since 1824. Most eruptions are relatively small, although the April-May 1999 event generated an ash column that reached 45,000 ft above sea level.”
      https://avo.alaska.edu/activity/report_getter.php?need=current&id=403899&type=8

  4. I did some poking around and managed to snag a copy of an IMO internal memo with their planned release schedule.

    Keep in mind, this is unofficial, so they might make some changes, but this looks promising:

    Summer 2021 – Reykjanes Fires Episode I: The Phantom Mafics

    Summer 2022 – Reykjanes Fires Episode II: Attack of the Cones

    Summer 2023 – Reykjanes Fires Episode III: Revenge of the Rift (now playing)

    Summer 2024 – Reykjanes Fires Episode IV: A New Hole

    Summer/Fall 2025 – Reykjanes Fires Episode V: The Faultline Strikes East

    Fall/Winter 2027 – Reykjanes Fires Episode VI: Return of the Lava

    It’s not clear whether all three future installments will be set in and around Fagradalsfjall, or perhaps will widen the scope to include other locations, such as Krysuvik or Brennisteinsfjoll. The memo didn’t go into that much detail; sorry. 🙂

  5. https://www.ruv.is/english

    BREAKING: public access to eruption is now CLOSED

    The police chief in Suðurnes has decided to close public access to the eruption at least until Saturday.

    An announcement states that it is being done to ensure the safety of tourists and emergency responders.

    Hjördís Guðmundsdóttir, communications manager for Civil Defence, says that the decision will not be reviewed until Saturday.

    There is a lot of pollution in the area, not least because of wildfires, and attempts are being made to extinguish these, says Hjördís.

    The police chief says he cannot guarantee the safety of those who enter the area under these conditions. It will be windy today and tomorrow at the volcanoes, and the wind direction is unfavourable for hikers. The closure is now in effect

    Many people have also ventured into the defined danger zone and ignored the instructions of emergency personnel.

    Apparently tourist have also been extremely rude to rescuers and some refusing to leave have even had to be removed by the police. No wonder the area is now closed until Saturday.

    • The smoke from burning moss is apparently more dangerous than the volcanic gasses.

      • I’m not sure how much ground disturbance there will have been caused by the ice sheet during the Pleistocene. Anyway, the moss will have colonised pretty soon after the ice retreated, so it’s had some time to spread and form peat, which will burn slow for a long time. I wonder what this area’s climax vegetation was before men arrived to interfere? Or has it always been moss?

        • Looks like Iceland’s lowlands were birch/aspen/rowan scrub forest, quickly opened up by wood consumption for building, fuel and agriculture in the medieval colonisation period. Some acidification and heath growth in wetter periods too.
          So mossification happened in less time than I assumed.

        • I’d suppose that only the high/steep cones are from Pleistocene. They were subglacial volcanic cones, such as Grimsvötn’s smallest possible eruptions that remain below the ice. The high pressure of water/ice gives lava more stability to rise to tall cones.

          The present eruption happens on the flat southeastern flank of the shield volcano “Þráinsskjöldur”. This shield volcano must have occured during Holocene “naked” without ice cover. All the more low altitude parts of Fagradalsfjall are Holocene.
          Before humans arrived Iceland had many birchwoods. Humans cut all the birchs and let sheep eat the rest. It was an early agricultural-ecological disaster which led to the present shape of Icleand’s treeless landscape: https://www.skogur.is/en/forestry/forestry-in-a-treeless-land/history-of-forests-in-iceland

    • Hi Alice! The last I read in a post late in the evening of the 13th EST was that the area was to be closed indefinitely. I’ll try to get that clarified. I’m not surprised at the behaviors of the volcano’s ‘guests’, I having characterized them as attendees at a geologic ‘Woodstock’.
      i

        • They are not going to close indefinitely. They are waiting for the wind to die down and are in the process of putting out the wildfires which have spread too far. If nothing is done about it the whole peninsula might end up burning. Let’s hope for some rain.

      • I agree about the behaviour os some of the visitors. Most are people of sense who keep a sensible distance and respect the emergency rescuers but sadly the behaviour of a few idiots taint things for everyone. I think the behaviour of the two idiots trying to actually trying to climb the back of the cinder cone would have been beyond belief if I hadn’t seen the photographs! How can anyone not have the sense to realise that after 3 days that was nor solid rock? It could have collapsed at any time or a leak developed that they would not have been able to out run due to the tremndous volume of magma in the cone.

    • Iceland the land of fire and ice. Good Volcanoes, exiting to watch and extremely dangerous. Love watching them. But using words like “WILDFIRES”? As an Australian, Hold my Beer! This is a small BBQ. The 2019-2020 “bushfires” were more than twice the size of Iceland in area. 243,000km2 burnt, 34 human deaths, millions wildlife deaths vs Iceland is 103,000km2 as a total country. Yes, I know semantics and all that. It’s still dangerous, so be safe. Sorry, slightly triggering terminology from RUV.

  8. Any cam showing where the lava is flowing? I am more interested in the landfill at the moment…

    • I agree totally with you Jan, to me the biggest interest is in watching the lava flowing and the directions it is currently taking. So the viewing of this eruption from the cams has been a great disappointment this time around. Hopefully they will install cameras at somewhere where there is a good overview of the lava streams. Still I did tend to get addicted to the cams so perhaps it means my housework wont suffer so much this time around. 🙂

      • I looked here:
        – https://en-gb.topographic-map.com/map-gf51/Iceland/?center=63.89918%2C-22.19912&zoom=13&lock=14%2C111%2C314&base=4

        The map is not updated with the fill from 2021 though.

        It seems like the lava will meet the lava from Meradalur and then go on the outside (eastern side) of the valley towards the sea. Quite a lot of ground to fill in that direction. No obvious obsticles that would divert it to the north and if it goes to the north it must pass Keilir to get to lower ground. But also there it is quite flat, which means that most likely a tube must form for the lava to go to the Keflavik road and the coast. Iceland population and infrastructure is probably quite safe this time as well (it is a relativation, but anyway).

  9. Watching the mbl.is panorama webcam, the lava front has pushed on past Kistufell and is spreading out camera-wards.
    With the lens distortions ad distance, it’s hard to tell what is just dark from burning, and what s lava further away.

  11. The eruptions 2021 and 2022 had the problem to happen in small valley which quickly filled with lava and drained the volcano. Now the eruption happens on 210m above sea level on a broad, even shield volcano. There is no way to drain the vent by the rising lava, because there is endless space to fill with lava. Also the magma pressure looks more healthy than during the eruptions in Geldingadalir/Meradalir. It happens at the center of Fagradalsfjall, while 2021 and 2022 were periphel eruptions with little breath.

    Maybe “Þráinsskjöldur” is the real Fagradalsfjall. The Fagradals Fires are going to migrate from year to year all over the shield, they will flood all possible directions. There will be many monogenetic cones like Piton or Mauna Loa use to do. Some will erupt longer/bigger, some will erupt shorter/smaller. We should expect lava flows which cross the Reykjavik-Airport highway and do ocean entries.

    • “drained” must replaced with “drowned” or “buried” … was a wrong word.

    • If Fagradalsfjall was following the same pattern as we are seeing now, Þráinsskjöldur is probably a continuation of Fagradalsfjall. The only difference is that Þráinsskjöldur did not occur during glaciation.

        • I might be wrong here, but I think that lava is from 2021. Did it ever reach there in 2022?

          The 3D model linked above indicates that I am right on this as well.

          But still. It will fill up the last bit of the valley and then flow around the ridge to the east, that is the reasonable development.

          • 2022 lava does not seem to have reached as far as the 2021 lava but it’s pretty close. So 2023 probably has met 2022 by now.

          • Sorry, the map I was looking at of the 2022 lava was dated 15th August 2022; the eruption stopped a week later so the lava would have gone further.

  12. The volcano is producing more lava now… at least it seems… fountain is biger and lava river too…

      • It does look more active, and the level of the lava higher than this morning. Maybe we will see a change in the flow with a collapse of a wall?

        Mac

      • If this is correct, it may indicate that fresher magma is now reaching the surface.

  13. “The employees of the Institute of Natural Sciences went on an aerial photography flight with Garðaflug’s plane at 15 and made a land model from them. Both models have now been processed. The conditions were even better than when the Pleiades pictures were taken and the plume did not cast a significant shadow on the land below it. When the data is interpreted together, the result is that the average flow was 14.5 m3/s between July 11 and 13. but the uncertainty in that figure is about 2 m3/s” https://jardvis.hi.is/is/eldgos-vid-litla-hrut-nidurstodur-maelinga-13-juli

    Partial quote. Well looks like the lava output has stopped decreasing as of late. Perhaps an output stabilization unlike last years eruption? If the current lava output holds I can see this eruption lasting much longer.

    • The map in the above link shows the lava extent for all 3 eruptions and indicates that the new lava field has some distance to go before it meets the previous flows in Meradalir. This doesn’t agree with some earlier statements.

  15. We now have a lava tunnel flowing from the crater. It also looks like the outlet from the lava lake is a tunnel and an overflow channel as well.

  16. IWhat amazes me most about this series of eruptions is how distinct and different each eruption has been. I suppose (and please correct me if I am wrong) that the distinct topography of the area where each has erupted has been a major factor in how each eruption has developed. It has also been like a ‘survival of the fittest’ with the strongest area of the fissure eruption depriving the weaker areas of magma until they become lifeless.

    • Alice, what I am hoping for is someone to have carefully recorded how each eruption has proceeded, as a video presentation with maps so that we can follow along. There are lots of youtube videos but they are only a tiny snippet of the whole eruption. For example, the cone splitting apart in the first week or so of the Geldingadlir eruption seems a popular theme for videos, but did anyone record how that fissure finally set up with the vent to the NE, and the two become the main center for awhile, the suddenly new fissure opened up north right underneath people’s feet and we saw that happen. Volcano Cafe observers were actually the first to see this happened and notified authorities (IMO) about this. Then the eruption center went back down south and finally one vent took over. I remember seeing the geyser action with lava shooting over 300 meters into the air. There was much that happened for the 1st eruption.
      Then I carefully watched the 2nd eruption. The fissure going up the northern hillside caught my attention, several times it seems as if further splitting might occur.
      This 3rd eruption is a real treat, despite all the moss fires, and someone actually caught on their drone camera the 4th fissure opening up realtime. Very spectacular! There was a lot of gas pressure when the lava shot out of the ground. I was recording the south and north Reykjanes cameras and caught the final last push at 16:38:39 pm when the lava broke the last part of the earth on its rush to the surface.
      I lament the loss of the FAF seismometer (meaning its crucial location and data from that location) as it was showing the harmonic tremors and gas surging when the 3rd eruption started. I am hoping that the new location will be just as sensitive.
      Yes, it is survival of the fittest, but we’re definitely noticing the northward movement of the fissure centers.

  17. I would love to know what the speed of the lava is down the waterfall, with daylight disappearing, you can really see it move.
    Mac

  18. To allow the moss fires to be extinguished, they closed the area to the public.
    The moss is still burning.
    I suspect it was to prevent “Just Stop Lava” protesters arriving due to the pollution. 🙂

    • You’ve just given me an idea of where to send all the JSO loons…. #fireyloons 😈😈

  19. I came back to check up on the best camera view https://www.youtube.com/watch?v=yJfiMhqLgTY right now at 22:18 pm UTC and the lava must have gotten a bit hotter, because it has eroded a channel back down close to the original level of the fissures when they first started. About 2 hours ago, lava was pretty high up inside the cone complex, but it has dropped a good 8 meters or so (my best guess) and it is definitely noticeable.

    • Also the southmost fissure vent is back in operation again, jetting occassional splashes of yellow hot lava into the air.

      • Which vent is that? Are you talking about within the main cone, or separate from that? Which camera is showing it, if it is separate?

        • it is in this camera view https://www.youtube.com/watch?v=yJfiMhqLgTY but back up the video to 22:20 pm or so and you will see this vent ejecting lava like a small spatter cone. It is tucked inside the view of the lava channel, but right just before the lava pours from the cone complex

          • Aha… I see it now. Thanks for the clarification. Looks like it isn’t doing it right now, but now it is making some major spillovers right out of the gate, almost like either the output is occasionally too much for the newly formed tube to handle or the tube is being constricted/blocked periodically.

  20. There was a vent wall collapse (nearest the observor) at 22:39:42 pm on the https://www.youtube.com/watch?v=yJfiMhqLgTY camera and lava flooding in is progress. This collapse has opened the door for a change in the channel drainage to occur. At 23:00:54 UTC we see jetting activity in the channel. Approximately at 23:04:55 pm the flow rate begins to exceed the channel capacity and lava overflows begin. This is obvious at 23:05:15 pm, as it is clearly seen that the lava has overflowed the banks and is spreading out. At 23:26 pm, it is obvious to everyone that the lava flow m^3/sec rate has increased and the lava must be accomdated by spreading in th general area.

    See https://www.youtube.com/watch?v=yJfiMhqLgTY as mentioned previously in this post

  21. 23:05, existing drain path was not enough to drain the cone. Now flooding the area to the left and right of the cone along with the existing drain field.

    Mac

    • We have to conclude that flow rate has definitely incrased from 23:04:55 pm UTC (local Iceland time). Things are getting interesting.

      • Is it that the rate has increased, or that the tube just keeps getting blocked by pieces of the inner wall that keep falling into the stream? (Not saying you are wrong; I’m seriously wondering). OTOH, it wasn’t obvious that the flow was lessening further downstream, which you would expect to happen if the tube was actually being blocked, so maybe the output really has increased. Either way, right now it looks like the lower portion where the tube opens up again has widened considerably and the lava is flowing freely through it again.

        • Dan:
          Good point, I will have to carefully think about this. I was surprised by the large extent of the overflow, maybe that led me to believe that an increase in flow rate occurred.

          • At one time there were ‘guests’ of the volcano standing where they believed themselves to be ‘at a distance’. That location has now be resurfaced. I can just hear the chorus of expletive deleteds coming from those who might have been there and are now witnessing this video.

      • Each time a large section of the cone wall collapses, it seems to block the lava tube and cause an overflow around the forward base of the cone. This will add to the future base height of the main cone.

  22. BIG overflows around 23:05 and 23:50.

    I’m beginning to get quite annoyed with Mozilla though. Either browser updates or some interaction with recent Windoze updates have caused a multitude of problems. Worst is a serious memory leak that’s causing me to have to intentionally crash tabs now and again when the associated process gets too bloated — closing and recreating the tab within Firefox used to fix such leaks, but that doesn’t seem to work anymore.

    Problem #2 is that using the vertical scrollbar sometimes causes Firefox and everything else to minimize themselves, bizarrely. Dragging the scrollbar to the bottom seems to be the most common trigger, though other moves of the scrollbar can also do it.

    And it seems that something is causing Youtube videos to randomly pause and unpause by themselves. In addition to an incident the other day, I have encountered several pause-unpause-pause-unpause sequences today, not user initiated.

    I grow weary of not being in full control of my own stuff. I’m thinking that inventing the ability to update things over the internet might have been not such a great idea. For starters, it encourages organizations to rush changes out the door with inadequate testing because “if there’s a problem, we can always send out another patch next Thursday”. More insidiously, they like to take control of the updating process from the end-user (compare Windoze up to 7 or maybe 8, where you could download updates at your leisure, then install them at your leisure, then reboot at your leisure, with Windoze 10, where it’s difficult to even configure it so that it won’t just surprise-reboot right out from under you while you’re in the middle of doing something, let alone to postpone any of those things indefinitely), and once they’ve done that, then they like to use updates to put unwanted things in, like advertising, or to remove stuff that people have gotten used to using so they can rent it back to you.

    At least Mozilla is non-profit, so it’s largely limited to rushing things out the door with inadequate testing in their case. Though I don’t like the way they’ve started occasionally spamming their users by popping open an unsolicited extra tab trying to sell some VPN service or another …

  23. 23:56, Some very hot lava showing in the old discharge path.

    • another overflow at 2:20am.

      are we getting pulsing behavior?

  25. Another surge starting at 02:16. That makes four I’ve seen.

  26. Yet another surge at 03:40, followed by another freeze at 03:56:14.

  27. They seem to be at near-hourly intervals. They end when the blockage works its way out from under the “bridge”, usually accompanied by a big surge in the channel downstream of there — though oddly I can’t seek into the part of the stream where the last such surge occurred. I always land either just before it or just after it, and if I go to just before it and then don’t touch the controls, it self-pauses just before it would happen. The only way to unpause it is to seek to elsewhere. Someone apparently doesn’t want that surge to be seen? Though I can’t think of why.

    • Have you tried using the right or left arrow keys on your keyboard? They move you 5 seconds forward or backward in time.

  28. There is a curious feature inside the cone which I have watched the last half hour or so and I want to ask everyone a question as to what is causing this feature. In the camera https://livefromiceland.is/webcams/eruption2307_1 we can see a bright yellow feature on the back side of the cone which never changes shape. It stay bright yellow indicating very high temperature and studying it carefully shows that it is nearly constant.

    Could this be an area of high temperature volcanic gas release?

    Initially I thought it was the wall constantly caving off and being replastered by the hot lava fountains, but careful observation does not show this at all. All the rest of the inside of the cone cools off quickly and the yellow lava quickly turns pinkish-red, then red, then dark red. You can even see the lava spatter itself cool off and change color. But the spot in the back stays constant.

    I am curious as to what is causing this?

    Any ideas?

    • At 06:57:01 am, Sat a chunk of the wall on the left broke off near this constant feature but by 30 secs later the wall had cooled off to a very dull or dark red, thus showing that some heat source is keeping the feature yellow constantly.

    • I noticed a similar feature right at the far end of the fissure a couple of days ago.
      Looking for the same feature on a sideways view, it was clear that the foreshortened aspect was narrowing off sight of the first fountain to a narrow slot.
      I concluded that thi ‘permanent’ orange feature, which did remind me somewhat of the Hawaiian Pu’u O’o firehose, was in fact a slim view of the first fountain inside the far end of the fissure cone.

  29. Your right Randall actually looks like a lava fall, going back about 55 mins from now there is a big chunk of rock on its left-hand side that drops in.

  30. The lava surface in the channel is shiny. It’s reflecting the channel wall on the far side. This is clearly visible at 06:55, for instance.

    • The surface is constantly roiling and changing temperature, which is visible from the camera, but I don’t see much variation in the feature changing, say if it were a reflection. When the wall fell off this feature never changed. When the La Palma volcano erupted it has often 3 vents going and the southmost vent was nearly gas almost all the time. I guess the only way we could tell is to take a drone up and take a closer look and see if this is a reflection.

  31. Something unusual going on at 07:09, almost like everything shut off? Dark brown lava? very chunky lava? Hard to make out, look like rust being pushed out the vent area on the right. Hard to make out in the smoke.

  32. https://twitter.com/DottirGongu/status/1680095023168102401
    https://twitter.com/DottirGongu/status/1680095026167021569
    These nighttime images clearly show – for the time being – that there is an upper, visible, exit from the crater and a “basement exit” ( only visible lava tube on THIS cam ) from the crater …. but changes “are inevitable”.

    Here, the upper exit is no longer distributed, but additionally “feeds” the lava tube from above (looks like a bridge) – if the lava tube is limited “in terms of tube circumference”, the upper exit runs out …

    .. and the lava tube exit is getting further & further away …

  33. View from Reykjavik shows the impressive steam/gas clouds and also the shallow lava shield that rises to the right hand of Keilir:

  34. Vatnajökull is free of earthquakes, this seems to happen often when Fagradalsfjall is active:

    Is it impossible to get a dual eruption by Grimsvötn and Fagradalsfjall?

    • Would be interesting to see if there is a relationship between Grimsvotn and Bardarbunga caldera earthquakes and the Reykjanes eruptions.

      • The main relation is that during an eruption, there is a lot of seismic noise which affects seismographs across the island. It makes it harder to detect or locate weak earthquakes. So you get fewer reported earthquakes across Iceland

        • Yes, that is correct. Although it is only during the intrusion phase that there is a lot of noise, after the eruption stabilizes there shouldn’t be much noise in the Vatnajökull seismometers.

          Checking it would require making a graph of earthquakes over time, I might try to do it at some point, don’t know where to download that data right now.

      • The only link I can think of is the head of the mantle plume comes up near Bardarbunga. This causes doming. Faults across Iceland have to move to accommodate this doming (in addition to plate separation). This may make it easier for magma to ascend further from the plume.

        You’d need a massive earthquake data set and history of ground inflation to prove or disprove that, not least because there may be other factors involved. IMO “only” reports quakes from 1995, so not a long enough period.

    • I dont know about Grimsovtn but there is probably some sort of tenuous plate boundary between the MIR, which goes up through Langjokull, and Bardarbunga. Hofsjokull is a big volcano and it isnt on the hotspot exactly so it has to be there for some reason. But its rift zones also are parallel to those of Bardarbunga and the MIR so there isnt any transform fault like there is between Hakla and Reykjanes, which is another area that I have been very interested in seeing if there is any sort of loose relationship. It seems that spreading along the western volcanic systems of Iceland is strong at Reykjanes, but then most of it further north of Hengill is transferred to the east, using the huge rifts of the eastern zone where Laki happened. Some rifting still happens north of Thingvallavatn but it is probably better regarded as extensional intraplate volcanism than true rifting, the plate boundary is clearly not in this area nowdays. Probably in the more distant future only Reykjanes will have any volcanis in the western segment, although I dont buy the idea that Vestmanneyjar is the propagating tip of a competing rift, when neither it or Katla actually show any rifting tendencies at all.

      And there is the recalled comment that the last sequence on Reykjanes was about the time that the Vatnaolur eruption happened, which was from Bardarbunga. Holuhraun was not quite so big but was similar sort of scale of rifting event, and all 3 eruptions since then have been on Reykjanes. Probably a bit of a coincidence but the

      • And remember triple junctions, the most unstable geologic feature you can find, are also present. Ridge jumps have occurred in Iceland and it is entirely possible that it could happen again as the spreading center shifts locations.

      • There’s a microplate, the Hreppar Block, between the Western and Eastern Volcanic Zones. The WVZ spreads at a rate of c.8mm a year – 45% of the total c. 17mm spreading in Southern Iceland.

      • Rifting will happen where the crust is weakest, which in time (as the rock cools down) will be where it has cooled down the most, which explains the rifting from west to east. The areas next to the previous rift are also cracking under a lot of temperature stress, which makes it easier too rift there.

        Annd then we of course have all the other volcanic features with microplates, volcanoes and the hotspot.

  36. An interferogram view of the intrusion that fed the last eruption of Piton de la Fournaise. It seems to be a large sill under the eastern flank of the mountain. Piton de la Fournaise collapsing into the sea is a serious threat. These sill intrusions under the eastern flank are becoming more and more frequent. They generally dip seaward so they might end up fully detaching the flank.

    • So does that mean part of the volcano will go to Davey Jones locker?

  37. Based on the recent videos it looks liek this eruption will be a similar sort of event to the eruption that happened near Thingvellir in 1000. That eruption formed two similar cones about 300 meters long and lava flowed a maximum of 7 km. But the lava in those eruptions also didnt get confined in a valley liek the flows now will be nearly all the way to the ocean, so I expect the lava could have flowed further.
    To reach the ocean the lava now has to flow 9 km, which is trivial if it formed a stable tube (Kilauea regularly went 12-13 km and as much as 24 km with half the effusion rate by forming tubes) but as an open channel it is a lot less certain, and if the channel fails then there is now a thick a’a flow in the valley so later flows will need to go a different way which might be longer. So I am not expecting this eruption to reach the ocean but if it does that isnt entirely surprising either.

    The 1000 eruption also formed two separate and sizable cones, with unaltered pre-eruption terrain between. So that eruption also shows that even in slower eruptions that make a sizable cone the vent can still relocate a considerable distance away late into the eruption, several km even. And that eruption also formed on the gentle sloping flanks of a shield volcano, with the younger south vent actually being at a higher elevation. So new fissures opening later on near Keilir is still entirely possible even though the eruption has moved beyong the initial breakout stage at this spot.

    As a side note, both the north and south cones of the 1000 ad eruption are about 300 meters long and 200 meters wide. The cone now isa little over half that, so there is probably still a lot of growing to do.

    The 1000 eruption is also what got Iceland to convert to Christianity, apparently, in accordance with the legend 🙂

    • It can in the end become an Icelandic “Mauna Loa” with many effusive eruptions along Fagradal’s rift zone which was active since 2021. The old shield volcano of 8000 years ago will get a new cover with lava all around. The whole shield eruption may last 100 years, but with many breaks and episodes.

      • Is this a resurgence of Fagradals after 8,000 years of inactivity or a re-activation of Reykjanes volcanics after the several century dormant period following the last cycle in the Middle Ages?

        Or is it both? Any thoughts on why Fagradalsfjall didn’t wake up the last time Reykjanes was active? The proximity is such that it seems wild that the propagating surge of activity wouldn’t have woken Fagradals, but clearly it didn’t.

        • We do have two episodes of inflation/sill intrusion at Svartsengi (Thorbjorn), and more recently a dike intrusion at Eldey, all since 2020. So it does look like a regional awakening. Eldey was also active during the Reykjanes Fires, it erupted at least once, in 1211, making the two “islands of fire”, Eldeyjar, which are possibly the only postglacial eruptions of Eldey, judging from bathymetry.

          • Hector:

            Do you know the rate of dike intrusions in Iceland that don’t make it to the surface? 80% ? 65% ? We’ve seen 3 “failed (to reach the surface)” dike intrusions now just the past 5 years. The reason I mention this is that the underground activity has only recently become noticeable and observable with GPS and Insar, so there is still a whole lot of volcanology and magma movement that we don’t know about yet.

          • Hard to know, during the Krafla Fires about half the dikes erupted, 9 out of 17. Fagradalsfjall has so far produced 4 dikes, 3 of them eruptive.

        • This misplaced further down so I’m putting it here anyway:)

          It is probably both, because intrusions have happened on other volcanoes on the peninsula too. But Fagradalsfjall has been mostly dormant since the eruption that made Thrainnskjaldurhraun which was in the latest Pleistocene, when most of the rest of Iceland was still glaciated, there was a small eruption about 6000 years ago. So there could be a lot of magma available at depth, the first lava in 2021 was very high in magnesium so was from deep down with a lot of melting, it then changed to stuff erupted more typically in the area which has been the case of the other two eruptions too. So this event has its origins very deep down which means it could have a lot of fuel, so to speak 🙂

          The other thing is that there probably wasnt a progression neatly from one volcano to another in the middle ages. The first eruptions was at Brennisteinsfjoll but so was the last, and nearly all of it was not really recorded properly, only the rifting sequence out at Reykjanes and Eldey which was from 1200 to 1240. But there were two eruptions at Krysuvik and Brennisteinsfjoll after this, the last in 1341.

        • Really great info and explanations, thank you guys. That was one thing I was increasingly curious about (why Fagradals was waking up now and how it fits into Reykjanes cycles).

          Really could be quite a show going forward in the Capital Region for the forseeable future.

  38. The overflow is causing a nice lava falls at the moment. The main tube must be blocked again.

    • Fascinating changes in the architecture of this systems’ plumbing.

    • Any idea of what chemical composition the new lava is? It is definitely brown in color. This started earlier today around 7:09 am

  39. 14:20 and watch for a couple of min. The lava tube unplugged.

    Mac

  40. It is probably both, because intrusions have happened on other volcanoes on the peninsula too. But Fagradalsfjall has been mostly dormant since the eruption that made Thrainnskjaldurhraun which was in the latest Pleistocene, when most of the rest of Iceland was still glaciated, there was a small eruption about 6000 years ago. So there could be a lot of magma available at depth, the first lava in 2021 was very high in magnesium so was from deep down with a lot of melting, it then changed to stuff erupted more typically in the area which has been the case of the other two eruptions too. So this event has its origins very deep down which means it could have a lot of fuel, so to speak 🙂

    The other thing is that there probably wasnt a progression neatly from one volcano to another in the middle ages. The first eruptions was at Brennisteinsfjoll but so was the last, and nearly all of it was not really recorded properly, only the rifting sequence out at Reykjanes and Eldey which was from 1200 to 1240. But there were two eruptions at Krysuvik and Brennisteinsfjoll after this, the last in 1341.

    • The following is a compilation of C14 ages of lava flows of Reykjanes, calibrated, giving the year assuming no error, and then the range of error. They come from Náttúrufræðingurinn 52, page 137. I also included the historical reports I mentioned in the Reykjanes Fires article. I don’t remember where I found the historic records though.

      880 cal AD (650-1020 possible range): Hallmundarhraun lava flow in Langjökull. Stratigraphically overlies the 877 AD Vatnaoldur tephra of Bardarbunga. Very large 9 km3 eruption that probably lasted somewhere between a few decades and a whole century.

      990 cal AD (840-1040 possible range): Tvíbollahraun (also called Hellnahraun) lava forms in the Brennisteinsfjoll system.

      1010 cal AD (880-1160 possible range): Breiðdalshraun eruption of Brennisteinsfjoll.

      1120 cal AD (1000-1240 possible range): Ögmundarhraun flow of Krysuvik.

      1120 cal AD (1000-1240 possible range): Kapelluhraun flow of Krysuvik.

      Reported eruptions in Krysuvik in 1151 and 1188. A dike from Krysuvik cuts the Brennisteinsfjoll lava field in multiple places.

      1200 cal AD (1040-1260 possible range): Gvendarselshraun lava flow of Krysuvik (it is in an area where flows from Krysuvik and Brennisteinsfjoll meet, but the flow is a fast-erupted pahoehoe sheet which matches with Krysuvik’s style, possibly the 1188 eruption)

      1211 (Eldeyjar eruption)

      1226-27 (Medieval tephra, from Reykjanes system offshore?)

      1231, 1238, 1240 more reported eruptions

      • Hector:
        Could the 1226-27 tephra be from Eldey? That would be a possibility?

        • It could.

          The other option is Reykjanes. There is a small bay where the Stampar fissure system of Reykjanes runs into the sea, this bay is surrounded by thick tephra deposits so that it could be a 600 meter-wide crater formed during powerful phreatomagmatic explosions. This crater is the most likely source of the Medieval Tephra, I think. Reykjanes eruptions are far more powerful than Fagradalsfjall’s. The Stampar eruption formed a 4 km long subaerial continuous line of lava fountains which may have continued offshore, so water-interaction would have been vigorous. And an earlier eruption (historical or not) formed a lava channel over 300 meters wide.

        • It is documented in the Icelandic sagas as a ‘fire in the sea’. It was a 0.1km3 explosion, part of a longer lasting eruption off the coast but by far the largest explosion of the 3-4 years. The ash caused a ‘sand winter’. It devastated the tip of the Reykjanes peninsula but the ash fell as far as Reykjavik

      • Supposedly there were eruptions in 1325 and 1340 from Krysuvik, and one in 1341 from Brennisteinsfjoll. That last eruption was what made the lava fall over the southern sea cliff.

        You also missed the Husfellsvruni and Hvammahraun eruptions, which were huge probably over 1 km3. Unless you include those as part of Breidadalshraun.

  41. Mbl has a cam pointing at what look like the edge of the lavafield

  42. I would just like to express my extreme thanks to all who have been posting timestamps of the more interesting events. Family affairs keep me away most of the day so during the small window later in the day it is so lovely to know when to ‘turn back the clock’ to see the best events. That has been truly wonderful and I am sure many more than myself have appreciated that facility.

    • My take on it Jesper is that I would far prefer to see a ‘small’ Icelandic eruption than one on some far away moon on a far away planet. This current eruption may be ‘small’ but it is close by and it has moments of extreme beauty which I am blessed to see with my own eyes. No doubt, if in the furture long after I am gone, some video of an Ionian eruption would be able to be beamed to earth, then I would likely be as enchanted with it as you currently are. Please dont think I am in any way trying to ‘put you down’ Jesper as I have been amazed and interested by articles you have written on here.

  48. Please orient me with respect to this cam. Are we looking south down the valley with the new lava on the right? Or are we looking north? Thanks

    • That is a recording from 5 days ago, when the fissures had just opened. Hence, it looks so different…

    • And right afterward the *#&! thing went and paused itself again, and I can’t unpause it. What the HELL is the matter with my damn equipment these days?!

      • It’s not you. I have the same problem with the stream. :/

    • I was just about to post a link to the event , the overflow was stunning. It’s a pity the feed stopped for a bit.

      • It was caused by a collapse of the inner wall beginning around 22:50 leading to further collapse blocking flow to the lower channel if anyone wants to view.

Comments are closed.