Reykjanes forever ?

/ 30/03/2021

Colours of wonder. Image taken by Lisabet, March 23

The eruption is now some 10 days old. In some ways it has progressed as expected. The row of cones has focussed on one spot, although surprisingly it produced a twin (after exterminating the minor third). The lava is filling the valley but has not found an escape so remains well confined. The Icelanders are flocking towards the eruption: with scant regards for safety. The hill side next to the cone is no longer accessible (phew) but otherwise the sightseers get so close that it is at time hard to see what is smoke from the lava and what from the barbeques. I guess it helps not having to bring your own heat. For the people unlucky enough not to live in Iceland, two cameras have been put up with excellent eruption viewing, freely available worldwide. And of course, those showy Icelanders are using the camera to showcase their lives to the world. Their dogs, their clothes, their phones (a bit creepy to see someone on my screen take a photo of me), even their love lives. (Erupt with a kiss?) Yes, this eruption progressed as expected.

But in other ways, this is an eruption with surprises. Where do we start!

First, the location. The Reykjanes peninsula is chocker block full of holocene lava fields. The tip of the peninsula is still utter devastation, from eruptions that happened in the 13th century (weather and overgrazing may have helped preventing much recovery). But there is one area that has avoided all eruptions since the ice age: between the thermal regions of Krysuvik and the blue lagoon. And the lava decided to come to the surface right in the middle of the safe zone. why??

Second, the source of the magma. It is melted mantle material, without much (if any) melted crust. It has come from 15 km down, not instantly (there was a dike involved which provided temporary storage) but fast. It was expected that over 800 years of silence, magma would have collected in the crust, at 5 km depth or a bit more until there was enough to begin a new eruption cycle. Eruptions here happen cyclical, after all, with of order 1000 years between phases. Previous cycles indeed produced more evolved magma, indicating a more shallow origin. But instead, this magma came from much deeper.

Third, the stability. The eruption rate seems to have settled at 6 m3/s. You would expect the rate to decrease as the pressure in the feeding chamber decreases. That is not happening, as far as we know. That makes it very hard to know what will happen next. Is there now an open conduit to the mantle, allowing the magma to rise up at a constant rate? Or is it like a bagpipe, where a reservoir is slowly being squeezed out at a constant rate, which may be different from the rate at which magma is added to the reservoir? The answer to this will only come when we know whether the magma composition is or is not evolving. At the moment, the MgO content is measured at 9%, in two separate measurements 4 days apart. But that was a week ago and we do not yet know whether it has changed since.

Fourth, the volatility. If this sounds in contradiction to the previous point, know that this refers to how much gas there is in the eruption. It is not too bad. The tourists, even those uncomfortably close to the lava, are not keeling over from the fumes. (It is not healthy either, I should add.) Yesterdays’s reports suggest that this is because the mantle magma had been melted before, resolidified, and them remelted. The first melt had allowed some gas to escape. When the earlier melt happened is not known, of course. It may have been last century, or it may have a long time ago. It may even come from the origin as subducted ocean floor, with the first melt happening on the spreading rift in the ocean that preceded the Atlantic.

https://www.mbl.is/frettir/innlent/2021/03/29/kvikan_likist_mest_staerri_dyngjunum/

Fifth, what caused the flames seen at various times during the eruption? It very much looked like a candle flame, but what was the fuel? Lava may glow, it does not burn. Options are carbon from the soil, hydrogen from oxidization of iron-hydride, and sulfur burning to sulfate. It is only seen away from the strong fountaining.

How will it continue? The big question is, how long will it last. We will let our readers decide: the choice is yours. To give a useful number, at the current eruption rate, it would take 7 months to get to 0.1 km3, and 6 years to get to 1 km3, so it is related to how large you think this will become.

At some point the lava may spill over into the neighbouring valley. The entrance is out of view for both our cameras. But that is ok as the lava is not yet going there but is still flowing towards the deepest point in the valley, away from the exit. It may be a month before that changes.

The two valleys are called Geldingadalir and Meradalir. As pointed out here, those are horsey names, with the first referring the geldings (castrated) and the second to the mares. Apparently the latter got the better valley, with better grazing. The first valley is no more.

Various videos have been made by our commenters. Here is one from astropgraph99, recommended for those who like their lava fast. I love it.

If you like your lava at leisure, we recommend the timelapse by our Virtual commenter. I love this one too.

And some beautiful images taken by Lisabet, on 23 March.

Poll

The results of the poll are

Most votes went to a 6 month duration, with 29% of the votes. The options 1 month, 1 year and longer than 5 years each scored 20%. 5 years got 10%, and 1 week got 1%. Interesting, the people who expect that it will last more than 1 year, tend to go for more than 5 years. But overall, the opinion is that it will last months to years! We can take 6 months as the VC prediction.

Regrettably, two people had to be removed from the voting list as they voted many more times than once. We did allow for multiple voting, but that was in case people could not make up their mind. Not to submit the same vote 10 times or more. If this is you, consider yourself as having been told off and please take a class in Basics of Democracy – one person, one vote!

And of course, volcanoes will completely ignore our voting anyway. But the last we time we took a vote, Reykjanes came out as a high scorer for the next eruption in Iceland. VC commenters have a good track record!

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352 thoughts on “Reykjanes forever ?”

    • This is impressive and really beautiful. Great overview of the flow.

      • He’s freezing cold and shaking, but he wont give up filming.
        That’s the spirit.
        I hope this is a regular thing. Not the freezing cold bit!
        I think he needs a battery heated suit like ones the powerline workers use in winter.

        • I mean.. he has a stinky volcano right next to his toes. Not sure how he gets home with all that gear tho.

      • Can we watch these later? I have subscribed to his channel or whatever it’s called.

        • I just checked (clicked on the link), and yes, you can. Note, though: there seems to be some filler shots (during drone changeovers/issues/etc), so if something doesn’t look quite right, it probably isn’t.

  2. Etna’s going off again, #17. Lots of fountaining and a lava river.

  3. If the locals have not selected a name for the new Icelandic volcano, how about the “Armchairs of Doom”? Right now, the two eruption points look much like two armchairs sitting side by side!

    • Yes Carl, I like that. I did compare them to glacial cwm/corrie/cirque landforms a couple of days ago. 😀

      Many volcanic landforms and processes could be thought of as analogous to those in the other branches of geomorphology.

    • hægindastólar af dómi (from an English/Icelandic translator, so take it with a grain of salt….or lump of Iceland’s finest lava…)

  4. wow, big sheets of lava are flowing down from the south cone now 02:29 am

  6. Interesting small swarm south of the eruption site alo g the dyke. Is it pressure release making the dyke starting to shrink or is it increased pressure making it expand?

    • Not sure, but the eruption rate is at most about 1/3 of the apparent rate of filling of the dike that was observed, so I would assume the latter and that more vents will open eventually. It is either that or the eruption is going to get around 3x as big from the existing vent.

      I personally think it will do both… 🙂

  7. A piece falls of the left went at 06:39:40 nothing major, but seems to slow the flow for a short while

    • Really cool video. You get a good view of the southern end of the valley and it’s clear that the lava level needs to rise a lot before it can exit the valley in that direction.

  10. If this sounds “harsh”….oh, well….

    I truly hope that someone/something photobombs every single occasion for every single person who blocked the camera(s), for their entire life.

    • It has become unwatchable. People are now deliberately blocking view to advertise themselves. I am reconsidering Iceland as a volcano holiday destination.

    • Over on Facebook the worst perpetrators are being collected and judged.

      In southwest England, there’s a word for uncouth tourists and outsiders, grockles. It is generally a derogatory term, used in similar situations to this. It looks like Iceland needs its own new equivalent word for these trollish idiots. Do any of our resident Icelanders have any ideas of a word to be invented or adapted?

      Perhaps a twitter hashtag campaign is needed, along with a dedicated selfie camera they can all use. Ideas so far:

      #IcelandicGrockleTroll #FagrahraunTroll #GeldingadalgosGrockle #LavaSelfieIdiot #ScienceGrockle #GreatWayToRuinScienceResearch

      Suggestions welcome.

    • She seems content to make little bombs and allowing them to surround her in their embrace….till she kicks them out and into the boiling inferno she’s provided.

      Thought she’d give us a real show today with huge collapses, seems perhaps not today?

  12. Sudri seems to have just opened a blowhole in the roof of the grotto. Approximately 16:45.

  13. Bjarki, thank you for the 360 fly over link. That really helped me get an idea of where the lava is flowing.

  15. Spellbound watching the lava creep toward the K100 webcam this morning. Amazing.

    • This morning and lunchtime has been so busy I haven’t been able to tear myself away.

      I’ll just have to do the vacuuming infront of the cricket to calm down.

  16. Any update on if/when/where the lava will spill into an adjacent valley?

  17. Looks like another lovely day on the peninsula. Lots of bubbling going on in the perched lava pond maybe due to the rain. The pond looks like it will break out somewhere soon. It might already be happening on the left of the K100 view.

  18. Has the pooling level at Geldingadalur dropped a couple of meters overnight? Is that from greater outflow or reducing inflow?

    • Yes, it had build up in a raised lava pool and that pool seems to have sprung a leak. At this moment the lava flow seems low. The pool had a break-out overnight but it probably also feed lava below the surface. The steam suggests that the cracks in the back of the cones are growing. At some point they could divert the lava out of view of the cameras.

      • Is that a new fissure eruption now in progress at Geldinagadalur according to livefromiceland.is webcam?

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