Posted on by Jón Frímann

Katla volcano earthquake activity – Update 2

Earthquake activity continues in Katla volcano with activity dropping between swarms. It is unclear at the moment if this is going to result in a eruption but at the moment it is my view that chances of an eruption happening soon (maybe in matter of hours) is high. Official view (government) is more conscious about what is going on in Katla volcano and does not yet issues this type of statements.


Current earthquake activity in Katla volcano. Copyright of this image belongs to Icelandic Met Office.

Largest earthquake today had the magnitude of 3,4 at the depth of 0,1 km. Yesterday magnitude 3,6 earthquake had a fore-shock of magnitude 1,9 at the depth of 14,4 km. This is unusual and suggests that the reason for the current earthquake activity is an injection of new magma, rather than moving of old magma in Katla volcano system. For that reason I’m expecting more earthquake activity in next few hours. This change in activity appears clearly in the earthquake activity that has been taking place, the earthquakes that have happened have variety of depth, with most depth at 15,5 km and up to 0,1 km.

There appears to be a cycle of earthquake activity with quiet period between them that last for few hours at the time. The cycles appear to be getting shorter. I don’t know why that is, but this suggest that Katla volcano is getting more unstable as this earthquake activity. I don’t know yet if it does the same thing as last year (2016) when a swarm of activity started and then dropped after few months of activity. Few SIL stations appears to be showing slightly higher tone on 2 – 4Hz band (just two at the moment). I don’t know why that is. Currently the situation is quiet, I am however expecting that to change without warning at any time. If anything more happens remains be seen, but the chances are high at the moment.

Update 1

There has been a new depth record in this swarm. Earlier 15,5 km earthquake has been relocated down to 25,0 km depth. At this depth it is only magma that can make an earthquake, normal tectonic processes do not work at this depth in Iceland since Iceland is not a subduction zone with deep earthquakes. Just three new earthquakes have appeared in last few hours and current activity remains quiet.


Current earthquake activity in Katla volcano. Copyright of this image belongs to Icelandic Met Office.

There is a lot to suggest that this increase in earthquake activity in Katla volcano is not over. This quiet periods where also observed during large earthquake activity in August-2016. I don’t know why this quiet period happens, they just do.

This article is going to be updated today (21-June-2017) if something more happens.

Article updated at 20:56 UTC. Added new information.

63 Replies to “Katla volcano earthquake activity – Update 2”

  1. hi all . I been watching the katla live cam . I need someone to confirm if there is steam coming out in front of the volcano

    1. Katla volcano doesn’t make any steam. As a volcano it is 99,90% under a glacier and it doesn’t have any hydrothermal vents on the side.

    1. At least prepare to watch the Míla cams. Because I think this is about as much long period warning we are going to get on Katla volcano.

    2. It would be nice if the Mila cam wasn’t auto-focusing on the raindrops though!

  3. The most recent pulses of earthquake activity have lasted 3-4 hours with 12-14 hour gaps between them. If this holds, there should be more activity by 02-04 GMT 22/6/17. I’m certainly paying attention.

  4. A reasonably strong quake (MW 1.4) at a depth of 25 km’s, 2,6 km’s WSW of Habunga, today at 10:20 hours.
    Interesting!

  5. The 13th of july I arrive in Seyđisfjördur for a 3 week holiday on the most beautiful holiday destination on this planet!
    In 2011 I had to turn back at Skaftafell, because Katla had washed away the bridge near Vík.

    1. Have a nice Trip! I remember well 2011. We have to go through the highlands.

  6. How little/much would it take for Katla to finally ‘tip over’? Would it be enough if just a little amount of magma breaks through the crust to come in direct contact with meltwater to make the whole thing go boom?

    And is it established that the repeating shallow earthquakes are hydrothermal in nature?

    1. That I don’t know. What I do know is that minor eruptions start with little or just minor earthquake activity. Last such eruption was in July-2011. Larger eruptions have been historically documented creating earthquakes that are felt in nearby farms and village of Vík í Mýrdal. Suggesting earthquakes of magnitude 4,0 – 5,5 and maybe up to magnitude 6,0.

  7. We will have tho start watching on the cam keeping an eye on it.
    back over next year tho this wonderful country
    Explore more of it’s culture.
    We feel in love with Iceland with just one visit it’s such an amazing place.
    Katla will cause a real mess ones it’s blown mess flooding
    We went to the site of the 2010 quake area. Last year the devastation there was unreal.

  8. Somebody go clean that lens off!! All I can see is the same cliff picture on all the cams!

    1. That link is not working on my laptop and rarely on my iPad. Or it is the same static view. To bad, because it used to work perfectly. On my laptop there is not even a link to the webcam visible. Frustrating…

  10. You can zoom in and see all the latest erupions as they happen in HD.

    1. No zoom, sorry. I think only the holuhraun camera had that feature, I’m not sure.

  11. It is indeed working on my iPad now. I will try Firefox on my laptop. Thanks Jón

  12. Ah! I have got the problem. Chrome automatically switches of Adobe Flash. The site does work, using Internet Explorer. And enable Adobe Flash…

    1. I guess Míla has not updated to the latest html5 video standard. Flash was being used during the last eruption (Bárðarbunga), since then it has been phased out mostly.

  13. Jon, last year in Sept, you posted the following, I can see why you are concerned that this recent quake at 25km portends a much higher possibility of an pending eruption. So the question remains, how much more can Katla take with the decreased pressure from glacial melting along with fresh infusions of magma.

    I don’t know why some websites say that. The fact is that Katla volcano has inflated a lot in recent decades and has in recent months had some localized inflation inside the caldera (source: Icelandic Met Office, GPS data).

    The problem here is that since monitoring started (around 1990-ish) Katla volcano was already inflated to the point it was ready to erupt (as the idea goes), that suggests that more inflation is not going to happen. With next magma injection from deep mantle there is going to be an eruption.

    The data now (earthquake swarms) suggests that minor injection of fresh magma from the depth. The pathway for the magma seems to be clear from the deep mantle, based on the lack of deep earthquakes in Katla volcano

    1. This paper here goes into details about Katla volcano movement. It also says about earthquake swarm activity during the year 1967 and again in the year 1976 and 1977. Largest earthquake in 1967 was Mb5,0 (01-April). In June 1977 a magnitude (Mb) 4,9 or (Ms) 5,0 happened. It is a question if this is a repeated pattern of injection of magma and the subsidence (magma withdrawing from the system). I don’t have a good answer to that question. But this older earthquake swarm that where unknown to me until I found this science paper bring up a interesting questions.

      The paper: http://onlinelibrary.wiley.com/doi/10.1029/2006JB004851/pdf

      1. I guess we would have to look at the GPS positions prior to the 60’s and 70’s up to current. I didn’t find mention of deflation in the article and I am unsure of Katla’s current inflation related GPS measurements

      2. Before GPS they used tilt measurements. Less accurate but told them when a inflation or deflation happened. GPS usage started sometimes in the 1990’s I think. I have no idea when they started measuring volcanoes in Iceland full time with GPS monitoring.

  14. Jon, have you been watching the tremor plots for husbondi and grimsfjall?

    2. There is a storm in east Iceland at the moment. You are seeing the wind on the tremor plots. Wind is not going to quiet down until late Sunday as the weather forecast currently is.

  15. This something to worry about.

    Thursday
    22.06.2017 19:34:41 63.622 -19.392 21.0 km 1.0 99.0 7.3 km WSW of Goðabunga

    This is a deep earthquake that is deep in this volcano magma system. It seems that more magma is pushing into the Katla volcano system. Why it remains so quiet at the moment is a good question.

    1. 7.3 km WSW of Goðabunga?

      That’s way outside the caldera – in the area of the hypothesized cryptodome.

      Do you think that quake relates to an oblique feeder to the caldera – Katla proper?

      Or a more direct vertical feeder to the cryptodome or possible incipient new volcanic system in that area?

      1. This is the deep feeder system, this might be the edge of it as the magma feeder system is not straight line as I understand it.

        At this location it is outside the cryptodome that is as I understand it a lot shallower feature. This earthquake is on the edge of Katla and Eyjafjallajöklull boundary, right on the line according according the map I have of this area.

    1. I’m now estimating, based on historical data that there are 10 to 12 months left in this cycle. It is part of a larger cycle that I’m going to write an article about because if I’m right that means a big problem for Iceland.

      1. My money is still on a high end 6 happening before the end of 2018, hope I’m wrong but it’s not looking good….

      2. No eruption in Katla volcano has gone above VEI=5. Last VEI=5 eruptions where in the years, 1755, 1721, 1625, 1262. There are gaps in the data due to old age.

      3. Hey careful slinging that “old age ” stuff some of us are there already lol

  18. For those how wonder what an eruption is going to look like on the SIL network. Please check this article from August-2014 when everything was going crazy in Bárðarbunga volcano.

    I didn’t find the science articles I wanted. But I have the suspicion that new Eldgjá style eruption might be imminent. Maybe not in this eruption, but next eruption after it. I don’t have enough data to be sure about to so I cancelled the article I was going to write about it. I just wanted to write this down in the case I got this right. I might get this wrong as that is always a possibility.

    This is how an magma movement looks like before an eruption. This is from Bárðarbunga August-2014 episode before the start of the eruption in Holuhraun.

    http://icelandgeology.net/?p=4776

  19. We can’t guess Katla, nor Hekla. It’s notorious for not needing much tickling and it’s had a few lately.

    However as you say Katla is of major concern. This quiet spell is almost eery, although data will be reduced by the passing storm. We’ve had the Eyjafjallajökull event and Katla is due. The deep quakes are not good I think when this rears its head it won’t be small. But that’s just an uneducated guess.

    As usual it’s wait and see and watch those tremor plots.

  21. There was a fellow that posted some links to 3D diagrams of the earthquakes in and around Katla a while back. It would be interesting to see what the last two months would look like.

    1. Thanks Porsche928
      This 3D models give such more of a clear view of what is happening in these volcanoes

  24. Earthquake activity appears to be increasing again in Katla volcano. This is slow increase, now each swarm is around 3 – 4 earthquakes each with magnitude -0,3 to 0,6 or so.

    I’ve also got the first comment on my story about spelling errors in that story. Just one problem with that comment, there are no spelling errors in that story.

  25. Two things
    1/ the story proves your writers block is beginning to crumble thank goodness!!! I think the previous response meant “grammatical” errors not spelling errors but all in all a great start to a new chapter!!!
    and,
    2/ What the heck is going on north of Iceland NNE of Kolbeinsey a 4.1 and then a 3.5 just over three minutes later??? I feel like searching for Moses trying to part the north sea with the string of bumps being almost a straight line to the two biggies jolts up there!

    1. A lot of earthquakes all the way from Iceland and up to north of Kolbeinsey. Massive rifting? Seems like it!

    2. 1. The grammar errors (if any) will get fewer with time as I get better in English. I guess I need to tell that person that if I want a professional service I will request it.

      2. It seems to be normal earthquake swarm, at least for the moment. Due to location I can’t rule out that an eruption might happen soon, but there isn’t anything suggesting that it has started at the moment. But this appears to be powerful earthquake swarm.

      1. It’s also affecting a very long strip of the ridge. Seems like it’s picking up again.
        I have only been monitoring Icelandic volcanism/seismology since the Bardarbunga/Holuhraun event, but I don’t think I have seen anything like this during those ~3 years.

      2. The SIL network has problems locating the earthquakes properly, creating this strip of earthquakes on the map. They aren’t actually happening at that location. They are more north, closer to the area where the green stars are.

      3. Aha, I see! Forgot to check the quality… But now that I do, many of the “99%” are set at 10.0 km. This must also be guesswork from IMO? The Largest EQ in the swarm was very deep: 25.5 km.

      2. @AK2:
        By “disinformation” do you mean “deliberately misleading falsehoods”? If so, would you offer some examples so that we can form our own opinions, please.

      3. Hi Andrew,
        This is Jon’s blog and I don’t want to write off-topic things. However, the blog you are referring to: the word disinformation might be a little harsh, misinformation is more appropriate. I will not go there to search for things that I found completely wrong, you have to check the facts yourself. At the time I found errors in maths and statements on chemistry from the guy who started the blog. He has also made ridiculous statements in linguistics where he obviously has no knowledge at all. He is also acting a like bully and appears to be rather misogynic. Not a nice blog from my perspective being a woman with an interest in volcanoes.

  28. I suppose if there was any volcanic activity up there it will take time for it to become evident wouldn’t it?

    1. The distance is around 355 km, an eruption at this location might not register at all on the SIL network unless it’s a really big eruption.

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