Posted on by Jón Frímann

Minor earthquake swarm east of Grímsey Island

Today there has been a minor earthquake swarm east of Grímsey Island (is in Tjörnes Fracture Zone). The number of earthquakes that have taken place at the moment is something around 20 to 30 earthquakes. All of the earthquakes so far are less then ML3.0 in size.

This earthquake swarm in TFZ is so far quiet and mostly small in size. It remains unclear as always if this earthquake swarm changes or starts a new earthquake swarm that is bigger. But this area is known for that one earthquake swarm starts a new one in the TFZ.

So far this does not appear to be happening in the TFZ. But it is worth mentioning that TFZ is highly active earthquake zone. But there are no volcanoes there. Except at the south and north end of the TFZ. Where the rift zone ends and where the rift zone starts again.

39 Replies to “Minor earthquake swarm east of Grímsey Island”

    1. They are missing the other major volcanoes in Iceland. Mostly Hofsjökull volcano and the other volcanoes that have not been so active in the human times.

      1. i think the placement is off too.
        😉
        Good thing we aren’t using this map to get around Iceland.
        Best!motsfo

  2. I don’t expect much from the quakes in the TFZ.
    Besides being so frequent, they don’t indicate any eruptions. That’s the routine of the MAR.
    But I’m curious about how Bradarbunga and Kistufell will evolve…

    1. On the contrary, there are some active volcanos there complete with underwater calderas. But… These seem not to be affected by all the quake-swarming there.
      If you look at the “Tjörnes Fracture Zone – Small” at MET you will see to dotted areas out in the ocean, those are active volcanic fields that has erupted after icelandic colonization.

  3. Motsfo, that is a very incomplete map of Icelandic volcanoes.

    This is a much better one (Google Earth)
    http://feww.files.wordpress.com/2010/04/volcano-map-of-iceland.jpg

    However, it only shows the central volcanoes. There has been lots of large volcanic fissure eruptions between Katla and Grimsvotn, and Torfajokull and Bardarbunga. There are volcanic moutains (active within the past 5000 years) north and east of Hengill, and also on both sides of Langjokull. If you travel to these regions, you can check those volcanic summits on detailed maps. I am also not sure whether Herdubreid and Snaefells are still active volcanoes of their own.

    I am surious to see what happens at Kistufell. It has been 100 years since last Bardarbunga eruption, no?

    1. Not if you count Gjàlp, this was a fissure between B and G in 1996. And the 1902 eruption was from the Loki system, which is part of Bardarbunga I believe.

  4. I cant help to think about this…It seems that all active volcanoes under and close to Vatnajökull (most of them connected to Bardarbunga) is acting up.

    Bardarbunga, Grimsfjall, Hamarinn, Askja…They all show seismicity at a fairly respectable depth. Is it the plume that is making a fuss? I mean they are above a hotspot..

    1. The more I read, the more I see stated that Iceland’s may not be a deep mantle plume, but more of a shallow (relatively speaking) entity. This idea comes from the chemistry and the little issue of Iceland’s plume not tracking the same as other plumes when they do the plate reconstruction. Many of them are in agreement on positioning when they work the plate rotations and movement out… yet Iceland’s doesn’t quite fit.

      Add to that the idea that the crust is rather thick for an island over top of a spreading center.. which generally thins the crust (spreading does that), and the evidence for it being continental crust over laying oceanic crust… like a pancake, sort of seems to have merit. That would tend to support the idea that the MAR interacting with the extra load might contribute to the energy of the hotspot.

      1. ‘The plume’ may be a mistake. It’s not proven or universally accepted, and if it exists, the structure may be a lot more complex than ‘the plume’ may lead one to believe.

    1. Ooops! that was supposed to be a reply to Daniel_swe

      To Jón Frímann , Oh, that will be why it seems quiet – because the earthquakes are drowned out by the storm.

      2. You know… it wouldn’t take much to convince some of our US congressmen the high winds might topple Iceland over. We already have one that thinks that stationing too many people on Guam will cause it to capsize. (Hank Johnson)

    1. Hehe now that is windy noise! 🙂 Either that or someone decided to use the helicorder as a football.

      But as Jon said, windspeeds at 35m/s so it might very well be just that.

  8. Dagur Bragason said: February 8, 2011 at 01:37, on the ‘Geologist worry about earthquake activity in Kistufell field’ post
    >>
    Here is another tool : http://www.natturuvefsja.is/vefsja/

    You can select active layers and under jarfræði(geolgy) you can select jarðhitasvæði(hot springs), sprungur(cracks), gígar(craters) an some other geological features.
    <<
    Many thanks for that and, if it helps anyone an Icelandic friend of mine (non-technical) has provided these translations.

    http://qvsdata.wordpress.com/learning-links/1084-2/

    Please feel free to add any corrections in the comments

    1. The news on this broke in Finland’s yellow-page newspapers with the headline: “Experts warn of a gigantic eruption in Iceland!”

  9. A new single Quake near Hekla:

    09.02.2011 13:38:55 63.933 -19.937 8.5 km 0.9 90.01 14.7 km WSW of Hekla

      3. MET-Update.
        The quake is now moved from the gamlarsprungur to the east, possibly at the south-west point of Hekla, and upped to 1,3M and down to 10,5km.
        Might actually have been related to Hekla then.

  11. Hekla seems to have gone back to sleep.
    I haven’t recorded a transient-event for more than 48 hours. The current activity is all at the Hella-strainmeter and that is more likely caused by Hengill then anything else.

    But, I still say that Hekla is prone to erupt anytime, remember that it met the requirements of MET for erupting more than 5 years ago.
    As such Hekla is in a way the biggest mistake from MET in some 40 years. All the other predictions have been really well met by real eruptions. But the MET prognosis in 2005 that Hekla would erupt in 1-3 years was obviously wrong, even though it was based on very good logics and facts. Instead Hekla has just gone on and on with inflation, straining and deformation that is now way beyond any figures measured for the two last eruptions. Remember that it passed the inflation-points of both 2000-eruption and the one before already in 2005 and the inflation rate has since then been hard and very fast. The same goes for deformation of the mountain towards Burfell/Isakot.

    1. Hengill volcano does not affect those strain sensors due to distance. Strain sensors only work in small areas of few tens of km. Not long distances like between Hekla and Hengill volcanoes.

      1. Sorry, was a bit inexact.
        I should have written Grensdalur (Hveragerdi), a part of the Hengill volcanic system.
        Hengill had a phase of inflation towards Grensdalur and Hromundartinur in the late nineties and early 00s. Hella is pretty much right ontop of that, at least way much closer then to Hekla;)
        Hveragerdi is about half the distance from Hella, then Hella to Hekla, same for Hromundartindi, and even Hengill proper (under Thingvallavatn) is closer or as close to Hella as Hekla.

        Grensdalur:
        http://www.volcano.si.edu/world/volcano.cfm?vnum=1701051A
        Hengill:
        http://www.volcano.si.edu/world/volcano.cfm?vnum=1701-05=
        Area-map with station (the most southern on the map), Hekla, Hveragerdi and the tip of Thingvallavatn:
        http://en.vedur.is/earthquakes-and-volcanism/earthquakes/southerniceland/

      2. Páll Einarsson talks about “lack of coverage from measuring devices” are there any plans on “planting” new devices there this year ?

  14. There was a hell of a storm here yesterday, near Selfoss.
    Winds have topped 115km/h with a maximum gust 147km/h. Amazing!
    Almost hurricane 1 winds. We even had damage in some windows of our home.

    But we still a part of the 50cm of snow that fell on the blizzard of last weekend.
    A new storm comes Friday.

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