Posted on by Jón Frímann

Intraplate earthquakes in Iceland

I see this morning that there are intraplate earthquakes north of Hveravellir. Intraplate earthquakes sometimes happen in Iceland, they also happen in earthquake swarms that can grow quite big. Both in size and numbers.

Intraplate earthquakes in Iceland happens on old fault lines or in old volcano areas.

71 Replies to “Intraplate earthquakes in Iceland”

  1. Jón: Never heard of that. Not in Iceland. Couldn’t that be related to Langjökull system?

    1. This does not appear to be that. This is between Langjökull north volcano and Hofsjökull volcano. But it does not appear to belong to there fissure zones.

    1. Most earthquakes in Iceland are in connection with the rift zones or the fracture zones (SISZ, TFZ). Intraplates earthquakes in Iceland are earthquakes that are not connected to any of those zones in Iceland.

      1. But a high percentage of Iceland’s earthquakes are associated with volcanoes, like Katla, Eyja, and those under Vatna … so does that imply that those volcanoes must be considered to interplate volcanoes … that is, like their interplate quakes, would those volcanoes have to be considered to not be assocciated with or exist upon any particular plate?

        I guess it is all just a matter of definition, but I’d say every volcano is on a particular plate, determined by its measured motion, and that therefore all quakes associated with that volcano are on a particular plate; and so as a consequence, those quakes would be intraplate quakes.

        But I understand your point that it isn’t like with the continental US volcanoes and quakes, since there are the huge rift zones in Iceland. So I can adjust my thoughts with the definition you give, even though it seems a bit unintuitive to me.

  3. Just a few days ago on the Hekla cam, http://www.ruv.is/hekla, there was a crater just to the right of the observation station that was rimmed with snow and ice, I just checked the web-cam today and there isn’t anything around it at all, just a unusual amount of ground fog/mist. I don’t know if this is signaling movement of magma or just warmer than usual temperatures, does anybody have any ideas?

    1. It just got warmer in the last days and the snow melted away. The weather is changing very fast here in Iceland.

  4. Jón: I am still seeing strange things at Hekla’s webcam (RUV) showing different topographies each time weather allows. As if there are landslides taking place there.

      1. Thanks Jón. Weather looks better and I don’t see what I saw before, because of clouds appearing to be a landslide.

    1. No big doubts over this, but I thought faults do not generally give quakes ranging over that big depth levels…

  6. Eruption plume from Merapi has reached 60000 ft, i.e. 18 km (see BTEB = Big Think Eruptions Blog).

  7. Jon, I read on Wikipedia that the 2004/2005 earthquakes triggered volcanic activity in 2005, as far as 600km away, along the same plate. Interestingly yesterday, there was both a 7.7 earthquake + tsunami, and Merapi starting an eruption, only a few hours apart. These events are 1000km apart, could it be a connection between both? Because if there can be a link in 600km, 1000km is not much more.

    Considering Iceland is such a small country, couldn’t there be a connection between events in opposite parts of the country. After all, how can there be a 600km connection in Indonesia, but not a 200km connection in Iceland??

    1. There is quite a possibly that this not interplate earthquake. But a magma intrusion into the crust like did happen in Upptyppingar few years back. But currently it is too early to know what is going on there for sure. So until we get something more useful I think it is interplate earthquakes.

      But if I am wrong, then I am wrong and nothing to it.

      Upptyppingar info, http://www.cprm.gov.br/33IGC/1353112.html

      It is quite possible that the Mw7.6 earthquake did trigger the eruption. But only because the volcano was already on the brink of erupting. But the connection so far is bit hard to establish at the moment. So this is more of a guess work then real fact.

      1. As you said Jon..It was already going to erupt…Maybe the 7.7 quake had it erupting 1 hour eralier or so but nevertheless..Merapi was going to blow no matter what.

  8. Even more EQ´s at the “Intra plate” location. The depths seems to differ. If this was magmatic intrusion wouldnt the depth be similar on all of them? These ranges from 100 meter to almost 23km. If it was indeed an old fracture it seems more plausible that it would produce these depths. It the old fracture ran from deep to shallow and it is moving abit now.

    Any thoughts on this? Basically my question is if the tremors were magmatic in natur (i.e intrusion) wouldnt the depth be more concentrated around one place?

    1. The earthquakes appears to be poorly located even if they have good quality. That might also be a error factor. But the closest SIL IMO station is offline and has been that for a long time now.

      Here is a google map of the location of one the earthquake (it happened at 17:35 UTC).


      View Larger Map

      4. Which does not rule out a meteorite or an eruption as the cause for the landscape shapes.

  9. Swarm continues strong:

    Tuesday
    26.10.2010 17:35:47 65.148 -19.585 4.1 km 2.5 90.02 31.2 km N of Hveravellir
    Tuesday
    26.10.2010 17:15:46 65.159 -19.575 3.2 km 2.3 90.01 32.4 km N of Hveravellir
    Tuesday
    26.10.2010 17:04:16 65.183 -19.592 5.0 km 1.7 99.0 35.1 km N of Hveravellir
    Tuesday
    26.10.2010 16:58:22 65.161 -19.580 22.9 km 2.9 99.0 32.7 km N of Hveravellir

    1. Given the range of different depths I would think that its an old fracture acting up. But of course Jon has to confirm it. 🙂

  10. The swams seems to get stronger. Are you still sure it’s got nothing to do with Langjokull?
    Oh and totally off-topic: Jon, why are most earthquakes near Godabunga in Katla shallower than 2km? (mostly even shallower than 1km) Thanks!

    2. This earthquake swarm is purely tectonic in nature. There is nothing volcanic there that I know of. But it might get stronger if there is a lot of tension there for some unknown reasons.

      Goðabunga sometimes has surface earthquakes (1km or less). I do not know why that is.

      1. If you look at the history the EQ at Godabunga or close to that station it suggests that 90% of all quakes are at 1km or less. This would be the result of seasons..In the beginning of the summer season and in the beginning of the winter season i would think the tremors would increase. This is logical since there is a (sorry for cursing) shitload of ice either melting or stabilizing (hardening)…I think most of the tremors, EQ´s and even GPS signals at Katla are so far seasonal signals and not a sign of eruption.

        Now Katla WILL erupt some day..As will Grimsvötn, Bardarbunga , Hekla and even Askja..

        But that day is not today…I think that all signals from the IMO net are normal at the moment even if some graphs go high. Most probably windfactor!

    2. Well.. it’s not definitively a micro-plate. Even that site’s author acknowledges that. Think block/micro-plate. Every thing I’ve read about it is that they are not sure of where the western boundary is.

  13. Need a little help, Jon, i hope You don’t mind…. but can anyone post anything over at
    Erik’s blog?? i tried twice and couldn’t post nor are there any new posts for some time.
    Anyone? Anyone?
    Pardon the interruption.
    Thanks,
    Best!motsfo

    1. Boris has also comments that do not pass on the blog of Erik. May be a bug since the move. I noticed a problem with the meter. It recognizes that the comments do not appear

  15. Tsunami Aceh 26 Dec 04,earthquake Jogja 26 May 06,Tasik earthquake 26 june 10, Tsunami Mentawai 26 Okt 10,Merapi volcano 26 Okt 10. It’s strange isn’t it?

    1. Strange?
      EQ Haiti 12 Jan 10
      EQ Chile 27 Feb 10
      Eyjafjallajökull volcano 14 Apr 10
      EQ New Zealand 3 Sep 10

      1. Fellows:
        Every time I have a pimple on the nose I get a cold. The doctor said one thing has nothing to do with the other.
        Are we not suffering from an equivalent sort of “Geological Hypochondria”?

  17. OT:
    Jón allow me to use your blog just to tell our friends that I have e-mailed both Erik and Jonah (Big Think) explaining the problems we are experiencing at BT Eruptions blog.
    Thank you.

  18. Jón: An earthquake just happened in Langjökull, but this time, further south from the swarm.

    1. Wednesday
      27.10.2010 07:50:35 64.614 -20.610 4.3 km 2.0 99.0 15.6 km SE of Húsafell

    2. That are is also known for strong swarms. Sometimes with earthquakes that are ML4.0+ in size. It is common to see small earthquakes there. But this area also has long period of quiet time between earthquake swarms. This area is a home to a second volcano in Langjökull glacier.

      Activity there is not connected to the activity north of Langjökull glacier.

      1. Sorry for disagreeing, Jon, but in my oppinion the earthquakes in both sides of Langljojull *might* be connected. What proof do you have they are not connected? Just because common geology says so? Forgive me that I like to challenge these established theories. I enjoy cracking the dogma and the lack of openmindedness in the scientific circles. Scientists so often defended their ideas as if they were religion “this has to be so, and that cannot be possible”. How scientific is that?

        There are some 100km volcanic fissures in Iceland, what if there is some unknown fissure or fault running all the way along the Langjokull glacier, that continues a bit to the north? I am not saying that there is, but there might be. After all, the earthquakes in both sides just started at the same time.

        A good scientific practice allows us to be curious with such kinds of coincidences and ask ourselves an hypothesis: “there might be a connection between both places and EQs”. It would be then interesting to check how often both sides experience activity that starts at the same time, after a period of silence there.

  19. Thanks, Rio!
    and a heartfelt Thanks to Jon for allowing us to stay connected!
    Best!motsfo

  21. Up close and personal with a zoomed in perspective plot of The Swarm.

    tinypic.com/24o5box.png

    It may be in a stack, but I think it’s more like a hinge point between large chunks of real estate than a volcano effect.

    But…. I just plot things.

  22. Hmm… the leading part of that got stripped off.

    http://i54.tinypic.com/24o5box.png

    I don’t think it’s the blogs fault, sometimes when I select the tinypic url it doesn’t highlight the whole thing. I’ve seen it before in non posting related cut-n-pastes with that site.

  26. Seems like the Comment-eating-monster ( In reference to the kite-eating-tree in the Peanuts cartoons is at full swing again. Chris ( and Jón Frímann if you read this) there was a problem with sending money to Jón Frímann because they charged him alot. I am willing to pay for the expenses but please it would be best if we could arrange a way were all the money gets to the person who had expenses and not to some obscure internetbank or whatever. Maybe putting the money in an envelop would be best or paypal.

    1. @Birgit, I am in the process of moving to Denmark. Far as I understand it is cheaper to transfer money into danish bank accounts then into Icelandic ones. The cost is something like 20 DKK (€1 = 7.6 DKK).

      I will hopefully get ash or lava from the next eruption in Iceland. At least I can try to get some examples of it.

  27. It might be possible for me to arrange this, since I have a bank account in Germany as well as in Iceland. But this is something we should discuss via email, not in the public.

  28. Thanks Jón Frímann. I really felt bad so much got lost. You know my email and home adress. And for Chris and others my last name is Hartinger and the email is firstname.lastname@aec.at. ( Ars Electronica Center Linz Austria) ( Again not writing it out so no bot can come across it and start spamming. When i do those images, it is more a private thing not a thing officially encouraged by my museum. But i asked the \boss\ of the BioLab and he said i may go on and do it, and if we maybe could find an expert who tells us what we are seeing. So this could become our own private hm hobby. And anyone who wants from the blogs may use the photos as they like.

    1. @Birgit: I know, I wrote you earlier about the offer of James Reynolds to collect some ash samples of Merapi.

  30. yeah i was not sure if this chris is the same as the one on big think but you dont happen to be Christian P.?

  31. Oh ok then the guy who contacted me has the same first name and the last name is the german translation for precious with an l at the end. Btw he is very nice man. And about the ash. I have checked it often since summer and no particle ever looked only remotedly like the very first view we got on yours. The one which looked like a cornetto at a magnification of 15400 fold. The white particles appeared more often in ash sent by Jón Frímann which never got in touch with water. I still wonder what the white stuff is. All the ashsamples were and are rather magnetic. It is still hard to try to spread it out very thin, so you can view it in a normal microscope. As long as my new friend is a chemist, maybe i can get him to analize this. But i dont know if he is willing and if he has the instruments and opportunity. He visted me during my workhours and i had to tend other visitors too.

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