Posted on by Jón Frímann

Bárðarbunga daily update 23-September-2014

This information is going to get outdated quickly.

Current status in Bárðarbunga volcano at 23:03 UTC

  • Largest earthquake from midnight was a magnitude 5,2 that took place at 04:33 UTC. Second largest earthquake today took place at 13:44 UTC and had the magnitude of 4,5. Other earthquakes have been smaller.
  • Bárðarbunga caldera continues to subside at around 50cm/day.
  • No major change has been reported today regarding Holuhraun eruption. That might be due all the geologist being on a convention today in Bifröst University.
  • Harmonic tremor suggest that more magma is flowing into Bárðarbunga volcano system. Increasing the pressure in it. Interestingly this does not appear to have created any inflation in the caldera, at least not any long term inflation is taking place in the caldera. There is less magma erupting from Holuhraun at the moment than is flowing into Bárðarbunga volcano, this is based on current data. It is clear that in new magma is going somewhere, but where is a question with no answer at the moment.
  • GPS data has stopped acting strange. I am not sure why that happened or why GPS data was strange for few days.
  • Harmonic tremor signal at 22:40 suggest a minor eruption did start and stop under the glacier. This was one of minor eruption that have been taking place in Bárðarbunga volcano for the past month. I don’t expect to have broken the glacier. If there is any glacier flood from this minor eruption it is going to small, since I don’t expect large amount of glacier being melted in this minor eruption.
  • Earthquake activity is moving south along the dyke from Bárðarbunga. That is not good since it suggests that pressure has started to increase in the dyke. This means new eruptions might start without warning where the dyke is located.
  • Storm is expected in Iceland tomorrow, with wind up to 35m/s. So detection of earthquakes is going to be difficult while the storm passes over.

Other new items I have not come across today. If anything new happens, I am going to add it here or write a new article if it is big enough event.

144 Replies to “Bárðarbunga daily update 23-September-2014”

  1. Fantastic update as always!

    Really wondering where all of the new magma is going…

    Keep up the great work!

  2. Thanks for the update Jon, we all thank you for all the hard work you put into this. We’re do you think the extra magma is going, is there a weak spot in the system its likely to erupt from.

    1. Based on the harmonic tremor I am seeing there is clearly something going on under the glacier. Not an eruption yet, but clearly something making harmonic tremor go up and creating harmonic tremor pulses. There is lack of earthquakes happening and I don’t know why that is. One explanation for that is the magma has not started to form a path to the surface at the moment.

      1. As there is some horizontal movement on the ground – and magma has to go somewhere – how about the Atlantic Ridge? If its opening up, can magma just go down into the ridge? There are so many quakes right now following the ridge….can it just open up – from one day to the other?

  3. Thank you very much for the update my wife and I have a vacation planned for end of Sept to UK and we have a stop over in Iceland been looking everyday at your updates thank you very much you Def have the best information on the activities there

  4. Regarding ‘tremor measurments’ and the 5.5 earthquake occurring on September 21. It is apparent that the 5.5 earthquake and subsequent drop of the caldera resonated significantly with a least 1/2 of the 64 treamor graphs in Iceland as seen here.
    http://hraun.vedur.is/ja/oroi/allarsort.html
    For what it is worth. Just an observation.

  5. Thanks Much for diligence and answering common questions What Do You Estimate Flood Prob Next Week Month Year Resp

  6. In addition to thanking Jon, as always, I want to thank all of you who have posted such great comments on this site. Many have provided links that have led me to more sites with much more information (and yet more links) than I would ever have found on my own. You have all added immeasurably to my learning experience about Bardarbunga, and I appreciate it!

    One site I stumbled on (dailykos.com) has a series of 34 articles on Bardarbunga by an author named Rei. I don’t know how to include a link, but if you go to dailykos.com and do a search on author Rei in the Diaries section with the date range of August 17 to “now”, her articles on Bardarbunga will appear. She writes in a way that is especially helpful to me as an American who struggles with the metric system. For example, the current lava volume of 400-600 million cubic meters is approximately the same as is in 200 Hoover Dams, and the thickness of the lava field is about 30 meters, the height of the Statue of Liberty including the pedestal, near the craters, averaging about 14 meters thick overall. Her article of 9/16 includes an excellent interview with geophysicist Porbjorg Agustsdottir, who was on the scene when the eruption began and collected the first lava samples.

    Again, mahalo for your comments and contributions, and warm aloha from Hawaii.

    2. I second this comment. I’ve been following Rei’s diaries from the beginning and they are excellent. It was actually a comment on one of those diaries that led me to this blog!

    4. Since I was in Battery Park overlooking the Statue of Liberty just two days ago I want to point out that it’s 90 meters from torch to ground. Even just the statue is 46 meters – so the measurement using the statue as a reference that would be closest to the lava height of 30m would be “heel to head” (34m).

      /metric compatible european

    1. Gervitunglamyndir cam sequences hint at a new vent at the lava fork north of the main vent. Need more frames to confirm this. Lava effusion also seems to have increased vigor

      1. Unfortunately one swing shows up and the other down, but definitely big swings. Now I am beginning to wonder if the gray glitches really are harmonic tremors?

      3. Are the big swings not after just ice on the instruments as was said before? Also the graph which counts is the the 180 min graph (the blue line). There was a discussion about the GPS not long ago.

      4. Yes, but it is fluctuations to a drop, or not to a drop. Have yet to see any instance of fluctuation which leads to a rise.

      5. High winds might cause these fluctuations. If fact the whole device could blow over in a gale. They must have anchored it down somehow, but time will tell if it is enough..

  9. It looks like many of the recent EQ’s at BB are just under 1km in depth. This may herald the intrusion of magma into the BB caldera which lies under about that amount of ice. The GPS is showing impressive movement even on the 180 minute average which should in theory smooth out this type of motion. All the Mila Cams show the usual vigorous effusive eruption, and the IMO seismometers show continuing and unrelenting harmonic tremors. I think we can put this one in the record books. The fissure eruption is already very large, and the only question mark is if the BB system will join the activity.

  10. Looking at GPS stations around the area, many of them showed quick deflation around mid-Sept, but have been showing signs of inflation since. So we are probably going to see more action real soon. Watch the harmonics start getting a little wild the next few days as a fresh batch of gassed up magma hits the surface. Big B still sinking whilst the land around pushing up. Something is going to give soon, unless most of it makes its way out the current eruption. Anyone’s guess at this point.

  11. AM coming up dry trying to find latest pics of the Holuhraun lava flow meeting the river. Anyone have a good link or 3?

    Thx in advance.

      1. This link provided by IngeB is to one of Rei’s articles, which I referred to in my post at 4:42 today. It’s is a great link if you want to read just one of her articles; they come out almost daily.

      2. XIE, XIE–THANKS THANKS.

        Those are interesting pics.

        The text mentioned a new lake and it sort of showed in one pic.

        That was a certain curiosity of mine. It seemed to me that there had to be some sort of lake(s) forming but I hadn’t seen any pics nor read of it yet.

        I’d still love to see several shots of drone or plane over-flights over the whole length of the lava flow’s contact with the river.

        I was just noticing earlier today that one river bank was at least several feet higher than the lava flow, at the time. And the lava flow was not that far from that bank–maybe less than 5 feet.

        I’d also love to hear some local experts talk about after a lake forms . . . is the riverbed’s composition such that the water will easily and quickly erode under the lava flow or around it . . . or not at all . . . or what?

        I also noticed in another map sort of pic earlier today–an evidently new part of the lava flow is massively spreading ?South? and some East. IIRC (If I Recall Corectly), there’s higher river banks not that far from the reach of that new section of the lava flow.

        It kind of seems like a toss-up as to whether the furthest North East reach of the lava flow will cut off the river first or the newer section of the flow closer to the vents will reach a higher bank and cut off the river first.

        It APPEARED to me, that either outcome would result in quite a number of square meters of water being impounded behind the new lava dam.

        Then one wonders, to what result . . . and how long would the dam hold and how thoroughly would it hold?

        It also crosses my mind that if this goes on as it seems to give every indication of going to do–for quite some time, that the lava dams would be significant in that whole broad area. It’s hard to tell from the terrain in the pics what the implications of that would be in terms of the amount of water dammed up behind such lava blocks.

        From more vertical air pics, it LOOKS LIKE that broad river bottom is rather flat. And, actually, there do appear to be some large flat expanses.

        Yet, when one sees ground level pics, the river banks can appear to be at least as high as half the height of a person or more.

        But then . . . how can I be sure that I’m seeing what I think I’m seeing in the pics! LOL.

        Besides all that, I’m merely an ignorant layman enjoying the pics and drama of it all–praying that no one gets hurt when the dust and ash settle.

        Thanks for Jon and all y’all’s thoughtful and caring contributions to the discussion.

  12. if you have been watching, the caldera is inflating, and the ice is dropping.

    in about a month, will reach critical balance, and the gps, and the seismos’s, will be down for the winter.

    gonna make a hard piece o jerky to swallow that. the best instumented volcano in history will be silenced to the internet by the crone of winter.

    speculate and enjoy, cuz it won’t get any better on info than this…

  13. Looking at the charts I see a slight slowdown in the drop and the chart going sideways. For it to keep up with the top and bottom trend lines it needs to drop in the next few hours otherwise it could drop without an earth quake as it has done before. Time will tell.

    As Jon has said he thinks fresh magma is moving, this could cause the slowdown in my little brain. once again Jon thanks for the fantastic up-dates

  15. IMO adds very shallow eq

    24.09.2014; 04:58:50; depth 0.1 km 3.4 99.0 5.5 km NE of Bárðarbunga

    which is on Jóns geophones too

  16. And the dots on the dyke line seem to be joining up now more and more with the caldera. Maybe a sign of the fissure about to erupt under the glacier soon?

  17. Just for a laugh, My grandson who is 7 is learning about the earth in school including volcano’s, as part of that they have been told about this eruption and have watched some of the footage on the web. He knows about my interest is volcano’s and this morning he asked me very seriously “Grandad is the eruption in Iceland a balsamic eruption”.
    I had to laugh.

    2. Long time since the last big quake. The ice etc has almost caught up with the last one. It will take another to start moving again. It really drops in jumps, but the jumps cause settling which takes a while to reach the surface making it appear much more smooth.

  20. …i dont know enough about this complex dynamics but it is possible that the subsidence stops and the caldera goes up again? -maybe caused by the increase of pressure from new deep magma.

    1. It’s one train of thought. I personally think that if the pressure built enough to lift a 10km * 2km piece of rock that it would blow out the side of the volcano where we’ve been seeing the quakes (i.e faults / weaknesses).

    1. I expect that to cause a renewed drop in the caldera. Probably noise is cancelling it out at present. 6km down may take up to an hour to reach surface though.

  22. Hi! Observing cams the Y shape ways of the ongoing eruption look confirmed, so the whole area next to the initial spot easy melts and become part of it…as I understood.
    It feels like it’s been enlarging during last 2-3 days..
    We will await IMO..
    as less EQ’s had been recorded in the area, as pressure has been easily released in the system (but constant).
    MILA look great today with very good visibility and good focus. Thanks folks!

  23. Please can you very kindly explain how you deduce that BB is inflating and how to interpret the amount of harmonic tremor? There is so much great information available right now but some of us don’t have the experience to read it properly.

  24. Please can you very kindly explain how you deduce that BB is currently inflating and the amount of harmonic tremor occurring? There is so much great data out there now but even those with some background in geology (a long time ago in my case!) may not be familiar with all the types of plots currently available – or need to know which are the key stations/signs to watch out for.

  26. Why are there almost no earthquakes in the Western part of BB caldera rim? There have been a few, but, compared to the Eastern ones they seem negligible. There was a 5.2 in the SW on September 16, a 5.0 in the NW on September 8, a 3.5 in the W on September 20, and a 3.3 in the W on September 19. There have of course been lower magnitude quakes as well, but they are few in comparison to the rest of the rim.
    It is easy to think the major weakness is on the NE since many earthquakes occur in that area, but perhaps the weakness is where there are only a few???

    1. We don’t know, but we do know that the shallowest magma chamber is slightly displaced to the north of the caldera, i.e. the eruption that caused the caldera was not dierectly centred over the magma chamber, si I personally suspect that is why.

  28. I note with interest that the current rifting around iceland seems to tie in with movements in the west and mid west of the usa.
    Some of these are probably due to gas fracking, but it seems that the movement of the american continental plate is maybe responsible for the increase in activity around mount st helens and other western seaboard volcanic sites.
    If I have read it right then st helens and yellowstones magma chambers are filling again,that is according to the usgs.
    I can not remember the name of the link on you tube, but the graphics consisted mostly of a globe with many lines and circles depicting earthquakes and their magnitudes on it.
    My question is, is the action in iceland causing these movements or are the movements responsible for iceland.
    Maybe the more learned members of the blog can answer.
    Thanks again to Jon and everyone for a great and informative site.

    2. I do not think Yellowstone’s maga chamber is filling again. I think it is rather near to being declared extinct. Hydrothermal activity can continue well beyond a volcano becoming extinct. We still have hydrothemal activity in Britain depite all our volcanos being extinct long ago.

      1. Yes, wrt Yellowstone, and with large dormant periods (last large one was 640,000 years ago, Iceland could only dream of such long periods of inactivity). There is little to indicated that anything is building. Yellowstone is known to be “breathing”, exhibiting upward and downward movement. And this is a hot spot volcano, not associated with plate boundaries. USGS info here: http://volcanoes.usgs.gov/volcanoes/yellowstone/yellowstone_geo_hist_88.html

      2. There is evidence that the hotspot under Yellowstone has erupted with regularity over the past 18 million years. While the hotspot is currently located in Yellowstone, Wyoming, former calderas can be seen throughout the Snake River Plain all the way to Utah & Oregon.

        It is considered dormant simply because it isn’t erupting. But extinct? Hardly!

        While it may be 10,000 years past due for an eruption (i.e. once every 640,000 years)… that’s only a fraction of the cycle [1.5%].

        However… for human beings with a typical lifespan of maybe 80 years… it might as well be extinct, as the odds of an eruption during a person’s lifetime is pretty much zero.

        But it will almost certainly erupt again.

  29. I find it very interesting that caldera subsidence is so regular and steady at 50-60 cm/day according to http://hraun.vedur.is/ja/Bardarb/BARC/. The larger 5+ EQs also come with a somewhat regular pattern. Some sort of stress builds and then releases. If EQs were caused by upward pressure from upwelling magma and then magma release into an underlying volcano chamber than I would think that this would result in uplift, yet it is the opposite, subsidence. Can anyone explain the larger EQs causing subsidence and the apparent larger EQ regularity?

    And another question, EQ reports for Bardar show that the larger quakes (4.5+) are 4-7km NE of Barbar. I assume that distance is with respect to the Caldera, correct? Why so distant? And finally, sorry so many questions, how far is the largest fissures and lava flows from the Caldera?

    1. Barbarbunga’s caldera is collapsing. The mountain is rising due to influx of magma under the whole volcano, but under the caldera slightly to the north is a magma chamber underground which is falling in. Below that are other magma chambers that are also probably falling in, a bit like when a mine collapses and a level goes, together with other levels above it.

      The caldera is dropping faster than the mountain is rising. What you see on the graph is the fall measured relative to sea level. The actual drop is even greater if measured relative to the mountain, because that is rising.

      I hope this clarifies.

      1. Thanks Treacleminer, that helps a lot. Are there GPS systems on the mountain that allow us to see the overall mountain uplift? Link?

        Thanks again,
        Greg

  30. mila webcams look like activity has increased today. Fantastic updates as always. thanks to all

      1. I agree could be wind noise…here’s a question…wouldn’t that come in waves? This feature started immediately after the 5.2 EQ…you can see the lines get thicker, and thicker, and thicker. So what I am asking, could the wind cause that? There are no breaks, and the line just keeps getting thicker…it’s been building for 6 hours. Just curious if wind could keep it sustained like that.

      2. It has looked like that before when it is just wind. We all got excited, then Jon put us right.

    1. Great news for Iceland, and us wanting to know what is happening in as much detail as possible.

      1. Great news. It’s all very well the nay-sayers saying they shouldn’t get funding, but Ejaf caused billions of £s in damages and insurance claims, so better understanding benefits us all.

  34. A gradual sustained rise shows on the Caldera GPS. Might not be real. Maybe the GPS device is being lifted by the wind. I am surprised it has not been blown over.

  35. It will have to have been lifted about 25cm…..Also, has the fissure reduced in output in the last few hours???
    If this is case it looks like something is afoot!

  36. The gps will have to have lifted 25cm!, a different pattern before the last 5+ mag eq was apparent in that there wasn’t any really, i thought the drop after the 5+ was making up for it, however….
    Is there confirmation that the fissure is reducing its activity?? Saw something on facebook saying as much but there wasn’t much info there…

    1. I expect the earthquakes to reduce because the smaller ones are harder to detect in gales.

    2. definitely not reduced activity at the fissure….as a matter of fact, it is powerfully venting at the moment.

  37. Hi Treacleminer, sorry i was referring to the subsidence rather then the eq’s, just using the 5+ as a before and after point…..good point about the wind,
    Thanks for info on fissure activity rolltideheather.

  38. It seemed like yesterday and the fay before that all gps movement was towards bb or to the west. Now the trend has gone back to normal, away from bb = expansion.

      1. If you go a the dates at left side you could see the dyke forming in the north. Around 28.8. you see the “fissure field”.

  41. Remarkable amount of uplift today. It’s already taken back at least half of this mornings drop following the m5.2 quake.

      1. I just took a capture of the image and drew straight lines across. The drop after the 5.2 was a little over 25mm and it has risen by 10-11mm since.

        It’s something that started yesterday – the tendency to rise, not continually drop.

      2. Andy are you using just the MA or trend lines or both. I have mentioned this a few times that the trend is changing. if you look back at the chart you can see that it started changing on the 20th
        To keep to the new trend it needs to have a fall in the early hours of tomorrow morning otherwise it will break out of it’s existing range. If it had stayed on the starting trend range in should have been down to -7m. I think it is slowing down slowly or changing it’s pattern, we should all get a far clearer view within 24 hrs.

      1. Great fireworks now again, let’s hope the wind keeps blowing the plume away from the crater in the right direction.
        They could zoom in a bit more…

    2. Drink a beer in front of the webcampictures…very meditative…
      and next time I wish you have some of the ladies here on your list (like IngeB and others and me…)
      🙂

    3. Well, you may have just saved us all a lot of trouble, BB won’t erupt if the magma goes cold, and I think hell just froze over 😛

    1. I saw this too.

      Thought first about water down Skeidarársandur, but there is nothing to be seen.

      It’s a bit windy there, but not so much.
      http://www.vegagerdin.is/ferdaupplysingar/faerd-og-vedur/sudausturland/linurit/st021.html

      BTW: To look for wind conditions in a certain region of Iceland, I prefer to use the plots from the Icelandic Road Administration.
      http://www.vegagerdin.is/english
      They also have a lot of webcams installed in all parts of the country:
      http://www.vegagerdin.is/english/web-cams/

  46. Maybe the folks in Iceland might get with the USGS and get some of these “spiders” that were first deployed during the 2004 dome building eruption at Mt. St. Helens in the US. They are rather inexpensive and can be deployed by a helicopter without a person setting foot in a dangerous area. The caldera area would seem to be a perfect location for these.

    Maybe the USGS would share the technology with the folks in Iceland.

    http://volcanoes.usgs.gov/volcanoes/st_helens/st_helens_monitoring_106.html

    1. I imagine the Icelandic Met Office, universities and geoscientists in general could certainly use help with resources and personnel. I imagine the ongoing workload has been extremely draining and it shows no signs of easing. The IMO is manually checking something like 200 earthquakes a day, for example.

  47. Checking a few big ones at the minute! They seem to chill out in between big swarms….fair play i think !!

  48. Is it just me or does it look like it is immiting more gas/smoke than normal? Like there is more pressure in there today.

    1. That will depend on weather. If the temperature is cooler and more humid, the vapor clouds emitted will look thicker. Also, if it were to rain on that hot lava it is going to create a massive vapor cloud.

      On a warmer day with less humidity, there will not appear to be as thick of vapor emitting from the vent.

      1. Makes sense. Thanks.

        Seems a bit darker clouding today/evening, but that could also be weather changes/atmospheric as well.

        There are also several M4ish EQs popping up right now (3.4-4.1). Ground activity seems to be picking up with that incline then slope over the last 10 hours.

      3. Yes, James, it does look more spectacular at night as the light from the eruption illuminates the vapor. That becomes invisible during daylight.

  49. A conjecture –

    If the current earthquake map for the Vatnajokull region is examined (see http://en.vedur.is/earthquakes-and-volcanism/earthquakes/vatnajokull/) , it seems like there is a parallel between Bardabunga and the location of the quakes relating to the fissue eruption, as there is with Askja and the linear patch of quakes near it. Both seem to show the same j-hook structure, with Bardabunga having an orthogonal or right angled feature to the fissue line, and the conjecture is that Askja is doing the same thing, except that the magma is still emplaced in the crust.

    See http://en.vedur.is/media/jar/myndsafn/full/mismkort4-rod.png and the article on webpage http://en.vedur.is/earthquakes-and-volcanism/articles/nr/2947 about 2/5 the way down, for a map of the right-angle feature on Bardabunga which would indicate some type of magmatic activity underneath the glacier.

    See also http://en.vedur.is/media/vatnafar/joklar/medium/bb-mismunakort2014-2011.png in particular for this.

Comments are closed.