Posted on by Jón Frímann

All quiet at Katla volcano

Currently everything is quiet in Katla volcano. At the moment the harmonic tremor level have gone back to normal levels. But there appears to be some earthquake activity taking place inside Katla volcano caldera. But most of this earthquakes do not appear on the automatic earthquake list that IMO has. But it might be impossible to actually locate this earthquakes as they might just appear on single or two SIL stations.

The glacier flood is over and the flood water have continued to lower during the day.

It is hard to know for sure what happens next. But the current events started around 17. June when earthquake swarms started to appear on the Katla volcano caldera. This has been developing rather fast since then. I do not expect that to change any time soon. But what I think was harmonic tremor pulses started around 12. June.

For now however all that can be done is to wait and see what happens in Katla volcano. As I do not think that this is over. But we might be in for an few hours or days of an break until something new happens in Katla volcano.

Icelandic News about this.

Einungis brúin eftir (Rúv.is, Icelandic, Picture)
Highway no. 1 disrupted for weeks. (Rúv.is, English, German)

58 Replies to “All quiet at Katla volcano”

  1. 7.1 EQ Honshu Japan Somewhere in the last couple of posts someone mentiioned a quake of this magnitude.

    1. That would be Peter Pan on July 9, 2011 at 14:16

      “…This eruption also will accompany with a major earthquake (> Mw 7.0) at some other place in the world.”

      And, typical of scaremongering, it’s not very specific. Just a doom and gloom. Interestingly, for Japan this isn’t that abnormal an event… especially since the after effects of the Mag 9.0 have that area of the plates is still trying to find the best orientation to sit at.

      “somewhere in the world” could be anything from the Marianas trench to Vanatu.

      1. There should be around 10 quakes of 7.0 to 8.0 following the Japan main quake statisticially. Also, on average, we expect 7.0’s to occur at a rate slightly above nominal due to plate readustments, so to say there is going to be a 7.0 soon is a given.

        To correlate this with an Icelandic event is folly until proven otherwise. Just another reporters opinion.

        Welcome back Lurk Dude.

      2. To clarify my statement re: expecting 7.0’s to occur at a slightly higher rate, my reasoning is because there have been so many large quakes recently on the Pacific Plate within the last 2 years, it is normal to expect an aftershock pattern would include several more 7.0+, although I have not counted those to date.

      3. Whats gonna be worth looking at is the Nankai trench. Large events there tend to come in pairs… one north of the wedge and one south.

      4. Haven’t really been anywhere, just hanging out on the periphery. Nothing really interesting to plot… at least as volcanoes go.

        Hekla isn’t going to give much warning, and Katla’s indigestion was worth a look.

      5. Are earthquakes and volcanoes totally random events or there are some rules and forces governing them? If these factors are existed, they are the same or not?

      6. Volcanoes and earthquakes follow different rules, although they are playing within the same sand box (our Earth). Eruptions or quakes can not predicted. In some rare occasions, major volcanic eruptions can be predicted days or weeks before (see e.g. Wikipedia article on Pinatubo eruption is 1991) from the symptoms the volcano is having.

  2. New long period earthquake in Katla volcano, this time the size was ML1.8 with the automatic depth of 1.1 km.

    Smaller earthquakes also seems to have started again in Katla volcano caldera.

    1. Jon, one thing that perked up my ears on this recent Katla activity is the levels of poisonous sulphurate gas warranting evacuations. I wonder how this portends what we might expect for a major Katla event in terms of gas.

      Anyone know of any scientific articles related to gas levels expected at Katla?

    1. This isn’t “the Geysir”, this is Strokkur. Strokkur erupts ca every 30 min but Geysir itself would erupt more sporadically – but you would know something was brewing underground.

      2. Oh well, yeah it has picked up speed after the quake in 2000. Haven’t been there for 7 years – too many tourists 😉

      3. Try a mid-winter visit – we had it to ourselves – five of us, and the snow and steam.

  5. Does not look like things are going back to like it was and a good morning to everyone.

    Sunday
    10.07.2011 08:35:00 63.638 -19.101 4.7 km 1.8 75.52 6.4 km N of Hábunga

  7. On Jon’s Hekla helicorder some very small (1-2 pixel high) bumps can be seen in the last hour of data; I wonder if they are earthquakes from Katla (some have been coincidentally appearing at about the same time). If yes, I also wonder if we could have a magnified view of that data so that we can see earthquakes more clearly, even if very small compared to the background noise.

    By the way, seeing Vedur.is earthquake map for the Myrdalsjokull area, it appears as if there are two main locations in the Katla caldera where earthquakes appear to cluster.

  8. is the harmonic tremor really over? What is interesting to me is that the normal alignment of the frequency bands is not yet restored (http://hraun.vedur.is/ja/Katla/oroi_hvo.html) this indicates that the harmonic tremor is still going on but it’s intensity is currently at the same height as background tremor.

    1. Blue and green lines being higher than red indicates mostly hydrothermal activity.

  9. Katla does not look quiet to me … whole lotta shak’n going on …
    http://i56.tinypic.com/2qdogvc.gif

    But the gps shows nothing happening:
    http://notendur.hi.is/runa/eyja_gps.html

    So I have to vote with the GPS and conclude nothing alarming is going on there … but the quaking makes it worth keeping a close eye on.

    Would most volcano watchers really be surprised if Katla erupted this year or next? Or are most of the volcano watchers just kinda waiting for it to blow fairly soon?

  10. 10.07.2011 08:44:17 Depth 3,4 km 2,1R Quality 90,01 7,0 km N af Hábungu

    I think Pieter that this is just the weather being picked up but I don’t think Katla is done burping yet.

    3. What weather? And even if, weather does only create disturbance with high frequency, and it doesn’t not affect the lower frequencies. What I’m pointing to is the fact that normally the high (blue) band was beneath the low frequencies (red and green).

  11. This is something which only happens on the plot of that particular hour at that time as it is moving along that line. Once it moves on to the next line/hour you will see these bumps go away or get ironed out so I am not sure they actually indicate anything important.

    I’m sure Jon can provide a technical reason why.

  12. From radio news at 10 o’clock (25 min ago)

    Mostly repeating what Jón has already said, except IMO says that this mornings EQ have been shallow and are not “unusual” for this place (sure, not since May rather than June this year Jón)
    Water levels in Múlakvísl are back to normal and civil response has been reduced though remain on watch for now.

  13. The blue 2-4Hz is at around 1300 background looks to be around 500
    Plus the small caldera quakes.
    Still ongoing, treat Katla with the same caution.
    If it had not been for the EJ 2010 eruption and the historical connection between EJ eruptions and Katla eruptions, I am sure we would have treated this event as one of Katlas usual stirrings Given 1955 and 99 etc’ but and a big but…. Something changed and Katla is as good as any good storybook gets, enthralling, captivating, special effects to die for, on the filming and visuals side a whole arsenal of cameras, web cams, satellites, its endless… There are governors, generals, Presidents, Prime Ministers, Kings and Queens all keeping an eye on this baby. The rush of vulcanologist’s and other scientists, enthusiasts, the press and just the plane old curious to Iceland before any flight grounding ash, would look like the invasion of Iceland on radar. I could go on…and on…

    Volcanoes are Volcanoes though, expect the unexpected perhaps. Lol.

    1. Nearly poetic take off. Just loved reading You. Sooooo well said.
      Makes me want to be Your Candy Cane… (sorry, know it’s not the joke of the year)

    2. I too liked how you worded that Rusty. Great imagery along with factual context! :>)

      1. GeoLoco and The Boston Volcano Heads.
        I am blushing now. Thank you both.
        I had fun writing that, sadly I was disturbed before I did another paragraph, the phone rang…

  14. Ah didn’t see that one (ran out of milk for the coffee)

    From what I saw in the news last night I put the location of 3 of the craters at k8 & k9 as in this picture where the eruption in 1918 is considered to have started

    http://www.raunvis.hi.is/~mtg/kmyndir/9100816b.htm

    and yes definently think that Katla might erupt now that some of the icecap has been removed, we’ll see in the next couple of hours – day if she picks up the phase in EQ

      1. You are welcome, it is a good picture.

        Of interest to others
        ==============

        The IMO web page says that it was the vents 10, 13 and 14 that ran on the 9th of July
        http://www2.hi.is/myndir/1004427 10

        Sorry it wasn’t translated but the first blue word underlined is the measuring equipment at Múlakvísl river, the second is Lágu-Hvolar and the third is a second meter at Múlakvísl, fourth is when the water hit Skálm lower in river

        http://www.vedur.is/um-vi/frettir/nr/2235
        Vatnshæð = water level
        Leiðni = dirt particles in the (glacier) water

  16. Good morning everyone:
    You guys have been doing a great work. Congrats.
    I agree with most of you: what we had yesterday was a preplay.
    Before logging in, I had just noticed the anomaly at Mid-Mork that Peter mentioned, differently from other stations – some are not yet entirely back to normal levels.
    There is a slight anomaly at Jón’s helicorder as well. Insignificant, maybe, but still worth keeping an eye on.
    And all those mini quakes? They keep coming in a steady basis (although the ones you mentioned above are not showing at IMO’s records.
    No expert here, but I’ve been watching those things for more than a year now, and I have to admit we are far from what you can safely call “normality”. What it may mean, in terms of a future eruption, I don’t know. But sure enough people are learning a lot now from these events.
    I like Irpsit’s theory. Not so sure, though, if there are connections between Westman islands and Katla and Eyjaf.
    I was kidding when I said we were under an “earthworm attack”. But there is some true behind the joke. It seems that there is a lot of magma looking for a weak spot to settle its nest under one of these Southern volcanoes.
    Very interesting, indeed!

    1. Well there was an “earthworm” lump at Hekla. And remember the worms of the science fiction, Dune. Now that is a BIG worm–but when matter is on the move under ground.

  17. I do not like the situation at Katla now: Jökulhaup followed by silence. The same happened at Grimsfjäll and lead to a larger-than-normal eruption.

    I suspect the scenario went as follows: The jökulhaup left the base rock more or less dry (at least not covered with a glacial lake). Thermally this means that the extra heat in the base rock due to magma must be emitted (or conducted into air or a small body of water, does not matter), which is significantly more inefficient than by conduction directly into the glacial lake (plenty of water). Why this is important? If there was a lake which absorbs heat by conduction, it would cause higher heat flux through the rock, which creates more thermal stress into the base rock (high differences in temperatures within the rock). Higher thermal stress equals lower strength under external pressure (due to magma from below) due to heat-induced stress cracking under pressure being easy.

    Now, if the glacial lake is absent, the heat flux out of the rock is lower due to lower temperature differences in the rock. At the same time, the rock must heat itself more, but it does not affect strength that much (we’re still in the brittle region). But, this does not lead to high thermal stresses! For an approaching eruption this means that the external pressure needed to break through needs to be higher, which translates into a stronger initial eruption. In case of Grimsfjäll the half a year period after the jökulhaup was needed to build up enough pressure to break through.

    If Katla stays now quiet for weeks or months, I believe we’re heading to a major eruption. I do not know if it will be a fissure one or a more typical plinian/sub-plinian.

    Caveat: Take the ponderings of a mad physicist too seriously!

    2. I also think we will see a build-up of pressure that leads to a large eruption, maybe later this year, maybe next year in summer-time, or maybe in 2-3 years. This is what we mean “eruption very soon” in geological language

  18. Katla is showing absolutely no signs of erupting in the near future or the next 50 years for that matters. The scientists say so. I live in Iceland and I dont like scaremongering. Katla has had its fun (yesterday). It has erupted and it was a very small eruption. Maybe the mountain has changed and isnt as dangerous as it once was. Thank god for that.

    1. Binni, applying emotion to form your conclusions only ends with disillusionment

    2. “showing absolutely no signs of erupting in the near future”

      Actually, that is completely erroneous. Just as I dislike doomsday fearmongering, I also dislike the ignoring of factual data. Not looking at it does not make it go away.

      Katla has all the pre-requisites to erupt… and it also has the temperament to sleep until conditions are better. This could be anything from a week to seventy plus years.

      I never count anything (with volcanoes) as “overdue.” But since we are looking at tidbits of evidence, and trying to second guess what it’s doing, let’s look at some statistics. It’s not my specialty, but it is enlightening about Katla.

      Fact one) Katla can erupt within twenty years of it’s last event. It tends to do this only about 12.3% of the time.

      Fact two) Looking at all events back to 920 AD, Katla has a VEI-3 or greater eruption about every seventy eight years. VEI-3 + is where it is probably best to consider it a full-on eruption. (makes the airlines take notice) We are right at the peak on the waiting time for that. (≈91 – 92 years from the last large one)

      Fact two and a half) Again, looking at all events, but back to 1920 BC, the VEI-3 or greater tendency jumps to 186 years. More data samples usually means greater accuracy… but these are events which may or may not have been found by lurking geologists. In other words, the resolution of what it found (tephra layers) drops. (time wise).

      In either case, the standard deviation is HUGE. for the 920 AD data, it’s 137 years. for the 1920 BC data, 302 years.

      Is it time for Katla to erupt? Yep. Give or take 3 or 4 human lifetimes.

    3. Iceland is what it is because of it’s exceptional geological context. It wouldn’t exist if there wasn’t this fascinating and terrifying potential for larger events. I’m against fear mongering, but the world is what it is, as Iceland is what it is, and let’s face the facts, as Katla is no supervolcano, but remains as active as possibly dangerous.
      People in Naples don’t care about Vesuvius and a lot don’t even know about Campi Flegrei, and no one should quit living there because of the geological context, but even though it’s no reason to deny the facts. One should be aware of his situation, without being in panic because of this knowledge.
      I rarely read anyone in this blog trying to exaggerate the facts (never…).
      Nevertheless, I’d be glad for You if You could never experience the full potential of Your faboulous country.

    4. @Binni:

      There are always two unwise ways and one wise way of thinking about any danger. The unwise are neglecting it altogether (your choice), and fearing it for no real reason (scare mongerers). The wise way is respecting it, i.e. knowing where it is,knowing how it behaves, and knowing how to cope with it (this blog tries to reach this).

      1. Hazard and risk management, what more and more governments try to build up, what anyone should independently do for himself. When You know, there might be some dangerous elements that can be dealt with, the rest is up to whatever – luck, the stars, interstellar powers… If You don’t know, it’s like You just give up as first reaction. Mankind didn’t grow like that… 🙂

  19. Hi can someone tell me on the IMO website when there is an earthquake which one of the following is in the Katla area:
    Hábunga, Kistufell, Kópasker, Selfoss, Hveragerði, Raufarhólshellir, Hveragerði
    Krýsuvík, Kópasker, Selfoss, Goðabunga

    Complete novice and just want to know which one to keep eye on?

    Thanks

    1. Miðmörk SIL station is located close to Eyjafjallajökull. This might just be traffic noise. Hard to know for sure.

      Currently the tremor is rather low. But it is not yet fully to background levels on many SIL stations around Mýrdalsjökull.

  23. Perhaps there is a slow eruption going on with pillow lava under the ice melt sub glacial lake or lakes. I bet its a right geological mess down under that ice.
    Because it is a slow eruption all we get is sulphurous gaseous warm water and depressions/holes in the thick glacier.
    I notice that the EJ eruption ash is buried by what looks like a good few feet of snow/ice, with th GV eruption ash fresh on the surface.. That glacier is thick. On the video of the glacier craters/holes there is steam visible at the bottom in some shots I think.

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