Posted on by Jón Frímann

Bárðarbunga volcano update for 10-February-2015

No mayor changes have been reported since my last update. Bárðarbunga volcano continues to subside at slow rate. The eruption in Holuhraun continues around the same rate as before. Sulfur dioxide pollution continues to be a problem. There are now also worries about the amount of sulfur dioxide that is bound into snow, since once spring arrives in Iceland (April – May) that snow is going to melt and flood the grasslands and rivers with sulfur dioxide pollution, when sulfur dioxide is combined with water it creates acid rain (that has also been a problem in Iceland).

150210_1820
Earthquake activity in Bárðarbunga volcano for the last 48 hours. Copyright of this image belongs to Icelandic Met Office.

Earthquake activity remains high in Bárðarbunga volcano, but there has not been a magnitude 5,0 earthquake since January-8 according to latest reports. Largest earthquake in past 48 hours had the magnitude of 4,7. I did notice today (10-Feburary-2015) several deep earthquake had taken place. This might suggest that magma is coming up from depth into Bárðarbunga volcano. It is difficult to know for sure what this means at the moment.

Correction of misunderstanding regarding Hreppar Microplate

Hreppar microplate has nothing to do with the eruption and rifting episode in Bárðarbunga volcano. Details on Hreppar microplate can be found here (page 18). Few more details can be found here (page 9).

New article schedule for Bárðarbunga volcano updates

With less activity in Bárðarbunga volcano I am lowering the amount of articles I am writing about it. Since it is hard to write about the same thing for five months. There won’t be any article on Friday (13-Feburary). Next update is going to be on Wednesday 18-Feburary. After that I am going to have weekly updates on Bárðarbunga volcano activity.

Donations: The PayPal button is going to return soon. Since I won’t be moving back to Denmark (as I hoped that I would do) I am moving it back to Iceland. It is going to take few days to finish that process. In the meantime it is possible to donate directly with bank transfer, information on how to do so can be found here. Other way to support my work is to shop from Amazon. I get a small percent of the sale price for each item sold.

185 Replies to “Bárðarbunga volcano update for 10-February-2015”

  1. Thank you for the update, Jon. I found the paper on the Hreppar Microplate very informative.

  2. Hi Jon.

    You has previously talked about the caldera subsidence and how you thought it would reach a point of no return.

    I think you said that point would probably be 40 meters?

    How much has the caldera now dropped since the start of the current activity and what are your current thoughts on the point of no return and any such resulting consequences?

    Thanks.

    1. That didn’t happen. I don’t know why that is. Currently the caldera (centre) has dropped some 60 meters, the edges have dropped less at the moment.

  3. Page 19, bullet point 4 of your link Jon. I disagree this has nothing to do with current activity. This 2008 report speaks of perpendicular rotation when there is evidence of multiplanar rotation. I have given many links to official reports in here before and been party to discussions on its involvement.

    I respect you Jon, but we’ll have to agree to differ on this point. Time will tell.

  4. Does anyone know if the existence of a shallow magma chamber under BB has been proven and if so how big is it?

    2. Well logic suggests,if you believe the prevailing theory that the subsidence is directly linked to the eruption at Holuhraun via magma drainage,that magma must be quite shallow?If you believe as I do that the eruption is indirectly related to the eruption,then the activity in the caldera must have a cause and that would have to be a shallow magma emplacement?

      2. Thank you for the above replies – very helpful. I guess we can say that known facts point to there being a fairly large shallow chamber where the magma quantity and state is unknown.

      3. @jb , I have never been convinced at the bb feed being solely responsible for holuhraun. There is similar evidence such a feed exists between bb and tungnafellsjokull, but no eruptive cycle has occurred.

        For this chamber to exist at a significantly higher altitude than holuhraun, yet to ask us to accept that lower bb chambers have fed holuhraun without draining the higher chamber defies logic.

        This upper chamber was filled from deeper source, therefore passageways exist which would have allowed it to back drain, which is not the case. That is why I am avoiding being complacent about the event dying down. There are several possibilities to explain this other than magma running out. The most obvious being that the intermediate chambers are not empty in bb, and that the event is dying down due to deposition as the temperature lowers.

      4. Maybe any shallow magma emplacement has reached a steady state,in other words its way more active then before last August but the state of activity has stabilized?

      5. @JB

        Why would the drainage have to come from a shallow magma chamber?

        In fact, the quakes running from the surface to depths of 10-12 km suggests the subsidence goes all the way to a very deep chamber that is draining. This chamber was not over pressured enough to create uplift (or this would have been detected with LIDAR runs years ago) but with a 10km x 8km x 10km deep pile of rock sitting on its roof, it is not surprising that it is being squeezed out. This chamber is being fed from deeper I believe.

        Also, I do not expect the quake activity to stop right away, that is one huge area of rock that will settle for a long time to come. Quakes near the surface and swarms of quakes have been happening from the beginning, this HUGE amount of rock does not move without making any noise unless it is lubricated.

        Put things into perspective

        There has been 26,797 quakes since the beginning of this event, 297 of them M3+ and less than 2km deep, over 1000 smaller ones under 1km deep. The entire depth of the sides of the caldera have experienced quakes so a few shallow ones now is nothing out of the ordinary

        So the sink has almost ground to a halt, the quakes are slowly winding down and the amount of lava coming to the surface has slowed to a very small amount. Saying this is not connected just does not support what we are observing.

      6. @ianf,what is the pressure condition at 10 km deep in the earths crust?Do you think that magma could just evacuate at that depth without pressure compensating from greater depth,I doubt the crust behaves that way otherwise there would be potential massive crustal destabilising events around the world?Would not the at depth pressure situation tend to equalise the effect of gravity on the kilometers of overlying rock?But under a much shallower depth of rock,changes such magma density or evacuation could cause subsidence?

      7. Before the rift, the pressure was equalized, the chamber was at a pressure that less than supported the roof of the chamber. There had been subsidence according to LIDAR from 2011 to Aug 2014, about 20 metres according to the chart.

        When the rift opened the existing route to Holuhraun this created an under-pressure in the chamber and the loss of support under the caldera. This intense seismic activity started with the actual eruption to the surface.

        So now this is coming to a halt, what is causing the pressure to balance the sink? I would suggest there are several possible causes, would be a great topic for discussion, I am still reading papers regarding this but would suggest that the downward pressure from the sinking “plug” is not enough to push material along the 45km crack and to the surface. It could also be that there is a feed to the chamber causing an increase in the chamber and the eruption is stopping for another reason. If the eruption stops and there is uplift in the caldera we will probably have a better idea what is going on down there.

      8. Also, this caldera is over 600m deep, this process has been going on for a long time, the structures to cause this subsidence are and have been in place and this is not a new thing to happen here.

  7. Wednesday
    11.02.2015 12:16:39 64.676 -17.460 0.4 km 4.0 99.0 5.1 km NE of Bárðarbunga

  8. Wednesday
    11.02.2015 12:46:30 64.661 -17.389 1.2 km 3.9 99.0 7.0 km ENE of Bárðarbunga

  9. i think that the pattern of the seismic movement has changed during last month . Before, the was a large sequence of micro-seisms with a “big one” each time. Now is a periode of calm and a little swarm with 2 o 3 M3-4 … like a heartbeat of the earth .

      1. And it’s increasing her frequency … i think .

        my english is very bad.. sorry. i’m from spain and here the education is … , is. Only is xD

  11. Don’t listen to Raúl. The education in Spain can be better, but isn’t that bad. I’m spanish too. I’ve been to college, learnt english, and everything under the public system. Raúl… Try to feel prouder of where you come from!!! Otherwise, your English is pretty good!! By the way, we have already reached that not return point by far. It must be more than 65 meters now. Probably there are two diferents chambers under BB. One is really swallow, maybe 2 km and the other is deeper, around 7km. But…, who knows what’s going on under 800 meters of ice!!!

    1. I also think that there is a large bubble shaped chamber maybe 5km across more than 10km deep, and there is a shallower flat pancake shaped magma chamber at 3-5 km depth.

      Holuhraun is not fed by draining magma from a higher source. Pressure from the subsiding caldera plug is forcing magma to rise against gravity from 10km+ all the way up to the surface at Holuhraun.

      1. Magma, as we are, is always subject to gravity. We are constantly falling. What prevent us from a free fall is the solid earth surface. When magma rises, its always against gravity. Now, when magma erupts, it can do so in many ways. Holuhraun is going on for several months and could do so for much longer.

        What causes a vent to be long-lasting or even permanent active.

        “Long-lasting eruptive activity from an open vent requires a permanent gas flow related to conduit flow or the rise of a volatile-rich hot magma to prevent cooling.”

        See:

        From reservoirs and conduits to the surface: Review of role of bubbles in driving basaltic eruptions (Vergniolle and Gaudemer):

        https://books.google.nl/books?id=cCGMBgAAQBAJ&pg=PA308&lpg=PA308&dq=magma+rises+against+gravity&source=bl&ots=jfYWhmwKk2&sig=AUVuTGnFLY2AK1dIzsLznVcnBdA&hl=nl&sa=X&ei=w2HcVN7DFYPwOaOrgLgM&ved=0CDcQ6AEwAw#v=onepage&q=magma%20rises%20against%20gravity&f=false

        Page 308.

        One condition to prevent cooling “could be related to the massive foam coalescence limited by viscosity (Jaupart et Vergniolle) , the flow of a stable foam in th ecase of a weak Strombolian activity, such as observed at Lava lakes (Stix, Vergniolle and Bouche, in rev.), or the existence of long an inclined conduits (Lane et al, James et al).”

    2. If this is magma on the move does it not show that the magma is now moving more freely without obstructions?

  15. I think we are getting to the stage of formation of a central vent. Smaller ones are diminishing, and the big one in the southern elongated crater will stay as the only one. One day, the current lava channel exit will be blocked by accumulating lava sheets, and we will have multiple lava lake spills in many directions. If it keeps erupting for a long time, we will get slowly a shield. But that takes a long time. Years.

    2. Perfect for roasting marshmallows! 😉

      Been checking on the caldera subsidence (GPS) a lot lately, and last few days there seems to have been practically no drop at all.

      2. Calderas rise all the time that does not necessarilly mean an eruption would be on the way,the subsidence is more likely to lead to an eruption by weakening the resistance of the overlying rock reducing the pressure any shallow magma is under causing gases contained in this magma to rapidly expand?

      3. Actually, overpressure leading to a rise in the caldera, puts faults and cracks under tensional stress causing them to open and allow upward movement of the magma.

        Collapse cause compressional stress which makes it harder for magma to intrude into the rock

        Also, just because the GPS in the caldera is stable does not mean there is not inflation within. If the area around the caldera continues to sink and the caldera does not then you could say the caldera is rising.

      4. When the centre of the caldera subsides ,it exerts a pull on the rim and this would be where the caldera would fail at the rim fault potentially leading to an eruption there?

      5. I can see how the outer walls would collapse inward but this again would create an area of compression

        By what forces would the walls be “pulled” apart?

      6. Perhaps the centre of the subsidence is an area of compression?Magma expanding outwards from the heating centre of the caldera pushing the subsurface rim out and at the same time as the centre dips pulling the surface of the rim in while the magma at depth pushes out?A percolating effect?

      7. If there would collapse the caldera, the result would be a tuff ring eruption, as at the ring fault there is the easiest way for ash/gas to escape. There won’t be any walls falling in. The center might then start to crumble and give way for some more eruptive activity. But I think there is no need to discuss this scenario at the moment, as everything seems to slow down and equilibrate. The subsidence must be caused by the shallow chamber. I can’t imagine that a lower chamber would cause the subsidence, the upper chamber would have an effect like a buffer to the movements.

      9. Then why does the column of quakes go 10km deep of the subsidence is caused from only at few km’s deep

        Why is there subsidence at the rim and the area outside of the rim if this is only caused by the small chamber inside the caldera limits?

        Where is the evidence of this heating magma pushing the rim out? The rim is sinking.

        Why, after all of this seismic activity is there no evidence of rising magma?

        The sinking from 10km+ deep is supported by of the evidence, but I have yet to see anything supporting your theories.

        It could be the Russians firing lasers in a cave under the caldera trying to set off BB to cause the European economy to collapse

      10. You are assuming that the depth location of the quakes is that accurate,there was a story some time agothat suggested most of the quake activity was quite shallow?Magma is also making its way from depth toward the shallow reaches of the caldera and this could result in the deeper quakes?The magma migrating outwards?,if we assume that the centre of the caldera lies over the hotspot then shallow magma must migrate away from the centre towards and beyond the rim to form the rim in the first place either through eruption or subsidence?A caldera does not have a conduit from a chamber like a stratovolcano but has a shallow magma emplacement that forms a rim fault and erupts via this mechanism?

      11. They may be inaccurate but it’s kind of laughable to suggest they are out by more than 10km, it is not that inaccurate. You are reaching on, read it back to yourself, it kind of suggests your ignorance on the matter.

        Why do you always make statements with a question mark?

        The rest of what you suggest again is not supported at all by any data in fact I will repeat the data refutes all of what you are saying

      12. @ianf, The question mark is to suggest that it is an opinion,idea or thought and is not being implied as a fact.It is an exchange of ideas,I take your ideas and see how it fits and put my thoughts out there,they are open to question and scrutiny.

      13. At least make put a good idea based on things that are fact not some made up idea pulled from who knows where.

        Do you want a discussion or just here to troll the board?

      14. So your idea of facts is a column of basalt 10km wide by 10 km deep that a lid of rock 10km wide by 10km deep is falling into under the force of gravity because it sprung a leak and this slipping and sliding into the low pressure void that exists at 20km deep is causing the quakes and the magma to squirt out at Holuhraun?Ok…

      15. Kids. Please play nice. I’m interested in reading both what you have to say but please leave out the i’m right, you are wrong. Speculate, postulate, hypothesize, theorize. I think a lot of us are here to learn, to try and understand, but in my humble opinion things are happening here that no one completely understands. How could they. I like fact backed by data and I like speculation fueled by ideas. What is happening here has to be a result of both. You may be right, you may be wrong. It doesn’t matter. Please don’t argue. 🙂 I’m not having a go at either party, just keeping in the spirit of this blog.

      17. @Ian F. The rim is also slightly subsiding because the shallow magma chamber is much wider than the diameter of the caldera, like a thick pancake maybe. This is just an thought. You could call that deflation of the whole area. The ring faults enable a greater subsidence of a compact rock mass in the caldera.

        @JB. The rim of the caldera is a relict of the former stratovolcano, which was there before the caldera collapsed long time ago, last time.

        @both. You can argue and argue, we need some proof, which would be seismic wave investigations and interpretations. Sadly you can’t do that on a glacier. So we will never find out where exactly the magma chamber(s) are or how they look like. The three-dimensional graphs of the earthquake locations does not provide enough info to make some clear interpretations. Seems you both like to go on and on about magma chambers, but it’s almost like arguing about where space ends.

      18. “Where space ends”,that is interesting i think i will formulate some thoughts on that and report back on it …lol.But seriously ianf is using imprecise and incomplete data to come to a conclusion that could be correct but most probably is not and then calls me a troll,if someone is going to use data to make a case then they have to have the knowledge and qualifications to back that up otherwise they are using our lack knowledge as a basis of substantiating their hypothesis?

      19. “if someone is going to use data to make a case then they have to have the knowledge and qualifications to back that up otherwise they are using our lack knowledge as a basis of substantiating their hypothesis?”

        I agree 100%, so why do you do this? I thought you said you were going away and never coming back?

        Anyway, back up your claims with something at least

        This is not my idea or hypothesis, it is the idea and hypothesis of many of the experts

        I am not claiming to be right, just going by what the data shows.

        If you are going to put words in my mouth at least get them right. I believe area that is sinking is probably about 2-3km wide by 3-4km long and goes down to a chamber about 10km deep

        Last word, yep, I just got it because I will not be back, this blog has being ruined by the likes you and all your ghost names.

        PS…when you graduate from Grade 8 and go on to the big boys school, you might learn that heat and pressure tends to expand things.

      20. Just a little note to the above conversation. It is important to form clear phrases (with . , ? ! signs where they should be), so that everybody can understand what you write (JB). And if you use some scientific expressions or words in your comments, you should know about them and what they mean, and use them appropriately in the context. That avoids misunderstandings and fights like the one above.

      21. @stefan,point taken,but my ideas have been consistent even if thoroughly wrong?Ianf is flip flopping between the drainage model,dead caldera and inflation(with no shallow magma chamber?)As I said before,I suspect a real scientist in this area would at most find my posts amusing for their factual errors and would correct points if they felt necessary but certainly would not accuse me of trolling.

      22. I want to point out this constant bittering about rather poorly understood processes inside a volcano is pointless. The old models of Bárðarbunga volcano clearly do not apply today, since current eruption has shown that the old models where wrong.

        @IanF, Bárðarbunga volcano magma chamber is not small. It is around 80 square kilometres wide. Depth is not known. That is a huge volume of magma that it contains, that magma chamber is around 10 km depth. No volcano is going to collapse that deep. Shallower magma chambers above this one however might. But for as long the main magma chamber continues to feed the smaller magma chambers at shallower depth that is not going to happen.

        I also want to point out that what happens inside a volcano is not well understood. So there is no point in getting upset about if people have different ideas about what is going on.

        Data from around Bárðarbunga volcano only tell us what they measure, what is not known is what happens at depth that can’t be recorded by instruments. This is everything deeper then 40 km.

      23. @Ian F, 11.59

        “Last word, yep, I just got it because I will not be back, this blog has being ruined by the likes you [JB] and all your ghost names.”

        Very sorry to hear that. I’ve enjoyed reading your posts, but I share your sense of frustration with some others.

      1. Hi Janet,
        this happens every evening and comes by the darkness.
        It is the same if you blow at night the smoke of a cigarette into a flashlight.

  18. Hi Enno

    ,,no wind, no fog and no more smoke … is this the end?,,

    Just thought you had asked had it come to an end still looks powerful to me and there were some shallow tremors this morning just before the graphs went silent since 10:00.

  20. Let me clear few things up.

    1: The area that is moving is larger then the magma chamber under Bárðarbunga volcano. That magma chamber is large, about 80 square kilometres wide, depth of that magma chamber is not known. Smaller sills exists higher up in the crust.
    2: Wider area is sinking with the lowering of the roof of the magma chamber. The crust around it is simply put, being dragged down by the force of this shift in the crust alone. This appears clearly in the GPS data.
    3: Only about 0,01% (best guess) of the magma chamber has erupted so far in Holuhraun. That did create a drop of ~60 meters in Bárðarbunga volcano, where the magma did come from.
    4: The reason why caldera collapse has not happened appears to be (based on current observations) that magma is flowing into the magma chamber at constant rate. The inflow of fresh magma is not high enough to prevent the volcano from subsiding, but it is high enough to prevent it from collapsing.
    5: Holuhraun eruption is the first eruption in a long series of eruption in this area. Some are going to be short (few hours), others are going to be longer (few months, years). Current number of eruptions in Bárðarbunga is 4 – 5, with many eruptions taking place under the glacier. Making confirmation difficult and often impossible.
    6: There is a rifting taking place alongside this eruption. That complicates this process many times over. Since it is not just the volcano that is erupting, it is also the crust in the area moving away from each other, creating canons in the process (they are soon filled with lava many of them).

    There is no point arguing about something in Bárðarbunga volcano. Since nobody knows what is going on. The best option is to wait and see. Speculations on when and where it might erupt next are more advanced then the other discussions that I have seen here. Since there is no point about arguing about some details that won’t matter, as the crust is about to fall apart in this part of Iceland in the next few days or years (impossible to know).

    This is also going to continue to alter the landscape in this area. Both on small and large scale.

    I also remind people to be polite in discussions here. I also want to remind people that what happens in a volcano is not properly understood and eruption behaviour of Bárðarbunga volcano is poorly understood.

    1. Well said, Jon.

      Since the magma movement is so unfocussed, there still remain many possibilities for either a jökulhlaup or for unanticipated eruptive development in the surrounding fissure or in a nearby central volcano.

      The hot, highly fluid magma easily flows 10’s of kilometers under pressure, and can ignite a distant magma chamber already in a critical state.

    2. Wow!

      80Km2. 0.01% erupted!

      Those figures are unfathomable!

      Great insight Jon.

      Thanks for that.

      How will such a large collapse effect the population of Iceland?

      2. The number could be conservative,which would make it even more unlikely the eruption of such a small percentage from greater than 10km would result in the effects we are seeing ,if due to drainage alone?

      3. There have been unofficial estimates that there may be four magma chambers, this was derived from data on areas within bb that were void of eq s waves.

        If that is correct then bb has a great deal more magma within it than has been erupted in holuhraun. Even if only the upper 8km dia chamber were counted, its eruptible contents would dwarf holuhraun.

  22. There’s a rather focused swarm going on at Herðubreið over the past 6 hours or so.

      2. What we can see here http://baering.github.io/ is, there are several hypocenters of a depth from 3 to 11 km down.
        But almost one epicenter! Most of the quakes are in a vertical line. What could that mean? Is it pointing on magmatic or tectonic behaviour?
        The rift-event surely reaches Herðubreið. Does it go any further to the north?

  24. Jon is of course correct especially regards rifting and GPS data, which is well worth daily monitoring if you are interested.

    Of particular interest whilst there seems to be a lull in activity, is the ongoing very high low frequency tremor being recorded over the past few days. If we temporarily ignore the usual culprits and examine sil stations like haukadalur we can see unusual patterns.

    I agree with Jon and have consistently maintained this is a much larger scenario than the event all are focused on. The extended GPS data supports that, and the data therein shows that the current lull is not the conclusion. I note comments about the potential scenario’s within the caldera, but we must remember bb is atop the mar, which means the forces exerted are not solely from inflation or deflation, there are torsional stresses that are very complex plus the hypothetical pressure from the mantle plume.

  25. Strong earthquake deep south on the Reykjanes ridge, it was far from land, closest one being some 3000 km away from the source of this earthquake activity. I am waiting for details and exact magnitude of the earthquakes that took place.

  26. M 6.9 Northern Mid-Atlantic Ridge 2015-02-13 18:59:11 UTC 10.0 km
    M 4.9 Northern Mid-Atlantic Ridge 2015-02-13 18:58:06 UTC 10.0 km
    M 5.3 Northern Mid-Atlantic Ridge 2015-02-13 18:48:16 UTC 10.0 km

    1. 2015-02-13 19:33:10.4
      09min ago
      52.51 N 32.27 W 10 5.3 REYKJANES RIDGE
      2015-02-13 18:59:14.7
      43min ago
      52.71 N 31.81 W 15 6.8 NORTHERN MID-ATLANTIC RIDGE
      2015-02-13 18:58:07.6
      44min ago
      52.80 N 31.21 W 2 6.0 NORTHERN MID-ATLANTIC RIDGE
      2015-02-13 18:48:17.7
      54min ago
      52.70 N 31.94 W 10 5.4 NORTHERN MID-ATLANTIC RIDGE http://www.emsc-csem.org/#2

  29. The last green star is going to vanish soon from the maps.
    This will be the first time since august 16.
    When and where will be the next mag 3+ quake…

    1. I look at the IMO site and I believe that it’s further East on that latitude compared to the current norm for large quakes this year?

      I think it’s exciting.

      1. I think it was at the Eastern caldera rim, also very shallow, 100 and 200 meters. Very anxious to see the movements of the caldera in the next few days. My guess is that it will rise.

  34. @scotsjohn,

    To me, your points below are much more than plausible and sensible.


    For this chamber to exist at a significantly higher altitude than holuhraun, yet to ask us to accept that lower bb chambers have fed holuhraun without draining the higher chamber defies logic.

    This upper chamber was filled from deeper source, therefore passageways exist which would have allowed it to back drain, which is not the case. That is why I am avoiding being complacent about the event dying down. There are several possibilities to explain this other than magma running out. The most obvious being that the intermediate chambers are not empty in bb, and that the event is dying down due to deposition as the temperature lowers.

    @Jon,

    Certainly, imho, the complexities are sooooo many and so complicated that even very educated “experts” are bound to be significantly, if not wholesale, WRONG about many aspects of this situation . . . RE Bard as well as Holuhraun.

    Certainly after-the-fact pontificating will offer plenty of chances to spout about one’s brilliance and brilliant prognostication guesses beforehand . . . or the opposite. Probably most folks will be significantly to mostly wrong about at least many aspects of the geological happenings and their causes.

    imho, this is still a great place to brainstorm and share ideas . . . keeping in mind that the best results from such have been documented to come when there’s NO NEGATIVE labeling or accusations or criticism of another’s perspective. It IS certainly possible to disagree WITHOUT being DISAGREEABLE.

    And an attachment disorder fostered need to be ‘RIGHT,’ ‘CONTROLLING’ or ‘WIN’ a blog argument . . . can be destructive to relationships, peace, blogs and discussions. imho, there’s no need for any such corrosiveness.

    1. With complex problems like this,to look at just a couple of parameters and deduce that things are coming to an end is probably unwise.For example in the last day or so it appeared the larger earthquake activity in the caldera had subsided in concert with the flattening gps curve ,then a cluster of mag >4 quakes occurred with no obvious subsidence.If the ice is still melting and the cauldrons enlarging then magma exists at shallow depth regardless of the seismic activity.

      2. I would guess that the subsidence has mostly stopped and there maybe some settling of the ice and fluctuations due to instrument error,I would doubt that any inflation would be as rapid as the subsidence?

  35. I have brought up the subject of the microplate involvement several times and I always refer to the mantle plume as theoretical, and I want to illustrate why. In a paper there is a simplified description, extract –

    “The unstable jigsaw tectonics that has persistently characterized the Iceland volcanic province can explain several major features. The development of a parallel pair of spreading ridges at ~ 26 Ma captured an intervening block which, if entirely oceanic, contains crust up to ~ 30 Myr old (c.f. Figures 5c and 6a). This block has remained beneath central Iceland to the present day (Figures 6a – e), during which time it has continually been loaded with additional surface lavas and perhaps also thickened by intrusions. It correlates well with the locus of exceptionally thick (> 30 km) crust beneath central Iceland (Figure 3b). This feature, usually interpreted as the center
    of a plume beneath Iceland, may thus instead, represent a thickened, subsided, captured
    microplate. This explanation fits the observations better than a plume since the latter predicts a laterally extensive band of equally thick crust extending to the northeast and southwest, parallel to the predicted plume trajectory, which is not observed (Foulger et al., 2003a).”

    The title of the above paper – Iceland is cool: An origin for the Iceland volcanic province in the remelting of subducted Iapetus slabs at normal mantle temperatures
    G. R. Foulger§1 & Don L. Anderson¶

    Another paper well worth reading to explain the importance of GPS data is –

    Overview of results from continuous GPS observations in Iceland from 1995 to 2010.
    Halldór Geirsson1,2, Thóra Árnadóttir3
    , Sigrún Hreinsdóttir4,3, Judicael Decriem3,
    Peter C. LaFemina2, Sigurjón Jónsson5,6, Richard A.Bennett4, Sabrina Metzger5,
    Austin Holland4, Erik Sturkell7, Thierry Villemin8, Christof Völksen9, Freysteinn
    Sigmundsson3, Páll Einarsson10, Matthew J. Roberts1, and Hjörleifur Sveinbjörnsson1

    1. Caution is advised!
      I can only warn the readers of any scientific articles in geology that geology, even with all those instruments out in the field, is still *highly* speculative. Except where there is already a general agreement (such as continental drift, as in point 1 on page 19 of the Einarsson paper, there is no reason to accept the speculations of even the most famous expert.

      3. The caution is more that you cannot always reconcile the papers you a reading to a specific situation such as this and of course understanding the papers,unless you have been to “big boys school”lol.Things at Bardarbunga seem to me to be changing now,worth keeping a watchful eye to see if this is a new trend?

      5. No. Science is not religion, and journal articles are not scripture.

        Each theorist forms hypotheses (that means educated guesses) and tries to support them with whatever past results they could find from the maze of past results.

        That’s why a consensus of experts is needed to make science work!

        That is why people have to go to college to learn and can’t just read the latest journal articles. Your professor is familiar with current research in the context of the history of the subject. The textbooks and the professors are there to provide experienced judgment and direction to newbies.

  36. From the safety of being out of range it appears that anything but a slow down is horizon. If my son or daughter was in the region I would by the a ticket off the island. We, the earth, has been significantly quite for the past 10,000 years and many have speculated why, while others choose to avoid the truth of it intirerly. My sense is that many here may not be seeing the forest for the tree in this case. The activity of the past year globally is spiking. You choose which hot spot to Challange the truth of this. Tectonic Plates that have been quite are active. Active plates are building up pressure. Dormat volcanos are waking up including super volcanos. Bard wil blow and I don’t think it will be alone either in the island or globally.

    1. Many stations indicate a rise in harmonic tremors at the moment.
      I would say the wind is responsible, as usual…

      1. Thank you Jon I am a pure novice learning all the time (sometimes though not good enough) apologies to all if I sound stupid sometimes I am just fascinated and trying to learn about Volcanoes 🙂

      2. Even a lot of wind now at one of the stations next to the eruption: http://www.vegagerdin.is/ferdaupplysingar/faerd-og-vedur/austurland/linurit/st052.html , average wind speed often over 20 m/sec.

        This could also be a reason, why there are not a lot of quakes on the IMO map, the smaller ones seem to get “swallowed up” by the wind – and then there is the weekend which means, not so many people on IMO duty to check on the quakes . Sometimes a lot more “appear” afterwards around monday noon.

  39. http://www.visir.is/section/MEDIA99&fileid=CLP33629 This is not exactly on Bárðarbunga, but a lot of nice film material (text regrettably only in Icelandic) about the west Icelandic peninsula of Snæfellsnes with its 3 volcanic systems: Snæfellsjökull, Ljósufjöll and Lýsuskarð. Famous stratovolcano Snæfellsjökull is the one you see on the first pictures. Petrologist Haraldur Sigurðsson is guiding the tv crew around the peninsula where is was born and lives again today and also shows his volcano museum in the small, but beautifully located town of Stykkishólmur.

    1. The last eruption on this peninsula was around 900 AD within the 90 km long volcanic system of Ljósufjöll. It took place within the valley of Hnappadalur. http://de.wikipedia.org/wiki/Hnappadalur (no English language article existing, pls. use translator)

      The big old lava field, which Haraldur shows also, is called Berserkjahraun (aged around 3.900 years, also volcanic system of Ljósufjöll) and connected with one of the famous Sagas.

      1. What I find most interesting about this area is that the volcano activity in this area appears to be moving east. With new volcanism starting again in non-volcanic areas (where once was volcano activity, but is now extinct). I don’t know why that is happening and this is only my view.

        My closest geophone stations to this area is Böðvarshólar and Hvammstangi (when it starts again).

      2. It also seems that the lava field, where his parents had a summer house – as he explains in the film -, was an inspiration for Haraldur to become volcanologist.

        There are a lot of mineral springs on the peninsula. Around them are mineral deposits esp. of iron compounds.

        In the very beautiful surroundings under the glacier covered Snæfellsjökull strato volcano, Haraldur explains in some detail the deeds and end of Iceland’s worst murderer Axla-Björn who is said to have lived there. The other big lava field in the background is about 8.000 years old and part of Snæfellsjökull volcanic system.

    2. @IngeB – 21:43
      Sorry, should of course be:
      “where he was born and lives again today”

  40. I also thought it always very intriguing that volcanic activity stopped on the Snæfellsnes peninsula when the rift moved on, about 7 mill. years ago, was then stop for 5 million years, and started again about 2 million years ago for unknown reasons.

    On the other hand, such very long breaks in volcanic activity are also known from other volcanic regions like the Canary Islands though of course this would be a very different geologic setting.

    1. Been to Snæfellsnes peninsula once, nice area (don’t know why i onlt went once).
      Bard 1 still snow covered whereas Bard2 blown out of alignment, getting a decent view of wind blown snow! 🙂

      2. Snæfellsnes is a marvel, well worth to go there often! Called not per chance, “Iceland in a nutshell”.

        BTW: In the rest of the film, Haraldur Sigurðsson explains part of the Snæfellsjökull National Park with Hellnar (dark and lighter coloured basalt, depending on the phase and time of eruption), Djúpalónssandur (dark and rust coloured basalt, the latter one oxidised by contact with sea water) and Þúfubjarg (the northern part of a former crater, the southern part totally eroded by the sea, the rim consisting of tephra layers from a series of phreatomagmatic eruptions of Surtseyan type).

        Later on, Búlandshöfði cap is shown, on the northern side of the peninsula, where an Icelandic geologist had discovered that Ice Age had its interglacial and glacial periods, after a boy from a near-by farm had shown him mussels in different sediment layers situated well over 100 m above actual sea level and these had been analysed. http://www.nat.is/travelguideeng/plofin_bulandshofdi.htm

  42. Some interesting quakes:

    15.02.2015 13:58:01 64,627 -17,585 4,2 km 1,4 99,0 3,1 km WSW of Bárðarbunga

    14.02.2015 23:38:32 65,080 -16,810 3,3 km 1,5 99,0 7,3 km SE of Lokatindur

    14.02.2015 11:25:05 64,571 -17,671 12,7 km 1,2 99,0 10,3 km SW of Bárðarbunga
    14.02.2015 11:16:47 64,549 -17,651 8,8 km 0,9 99,0 10,2 km NA of Hamarinn

    Deep (12,7 and 8,8 km) and halfway between the culprit and Hamarinn. Direction SW, hm ..

    14.02.2015 05:24:52 64,606 -17,586 1,7 km 1,0 99,0 4,8 km SW of Bárðarbunga
    (on the SW rim of the caldera)

    What are your thoughts on this?

  44. 16.02.2015 11:13:35 64.668 -17.462 1.5 km 3.6 99.0 4.3 km NE of BB
    16.02.2015 11:12:16 64.667 -17.464 2.0 km 1.6 99.0 4.2 km NE of BB
    16.02.2015 10:47:19 64.670 -17.454 0.1 km 1.4 99.0 4.8 km NE of BB
    16.02.2015 10:39:48 64.678 -17.418 0.1 km 1.4 99.0 6.7 km NE of BB
    16.02.2015 10:34:01 64.672 -17.470 1.2 km 2.8 99.0 4.4 km NE of BB

    GPS starts working again with the first eq at 10:34 🙂
    … and very, very clear view on MILA cam2 at the moment!
    http://www.livefromiceland.is/webcams/bardarbunga-2/

  45. Four very shallow quakes at Big B in the last 40 minutes. There have been lots of these lately! What is going on? Please comment if you have any ideas. I am wondering are these quakes magma or rift related?

    1. Well I don’t think its subsidence related,so that means its magma related.New phase starting?Magma could be closer to the surface and less able to induce larger quakes.Hey just my 2 cents worth, did not go to” big boy school”.

    1. Definitely interesting. As Holuraun is not deflating, pressure is still there. Size of the lower source is unknown. The amount of earthquakes and the big inflation/deflation there is indicating a magma source closer to the surface as well.

  48. Something going on worth a look. The GPS trace has been bouncing all over the place for the last couple of hours. A few minutes ago it was hovering at plus 8 metres – now dropped to minus 2 . I have never seen the yellow 180 minute trace move so fast. Has anyone got an answer.

    1. I think now that the subsidence component has ceased, the instrument fluctuations that were always present have become more apparent as they are now showing against the background of a flat line not a descending line.Oops I think I may have one too many drinks…

      1. Thanks for that and you may be right- although watching the rise and fall is conjuring an image in my mind of a boat on a turbulent sea. Is it possible that the eruptions under the glacier are forcing the crust up and when pressure is released either by venting or subsidence, it is plunging back down before it equalises close to the original level?

      2. Is not the GPS now located within an big ice cauldron? And the ice is flowing, but also breaking under the influence of gravity? So that there would be chunks of it tumbling down the – partially steep – walls of the kettle. I think this could be the abrupt movements we see. Or else hydrothermal venting deep under the ice.

        @JB: Pls. stop belittling yourself – it’s annoying! Let’s just stick to the subject – which is volcanoes and not volcano drinks or university degrees or whatever. 🙂

      3. No, I would doubt that because the gps track returns to much the same level it was on after the fluctuations,if it was ice moving then the level of the reading would change and stay in the new position.Make sense?

      4. My guess is a large block of the caldera floor was slipping into a shallow magma chamber and now this centralised block has locked in place,hence the sudden level off in the gps line,maybe compression of the caldera floor has locked the slippage of this block?

      6. Yes,it is flat,now maybe look for a response in the ring fault as the stress may now be transferred there?

      7. The Scientific Advisory Board made the following comment today in their update……..”the rate of the subsidence of the Bárðarbunga caldera is still significant.”

      8. Can’t imagine the caldera has dropped into a magma chamber however deep-seated. This would have shown by a “big bang” now, I think. 😉

      9. Is not the caldera floor at depth in contact with any magma chamber,so if subsidence is occurring it would be into that space through the chamber losing pressure or density?The floor quite often subsiding in large blocks?

  49. The way it is diminishing almost daily seems to indicate that the guy could be right about it stopping in early March.

  50. While the deflation and the eruption in Holuhraun are connected. They are not fully connected. The eruption can continue even if subsidence stops. This is going to be the case if the source of the magma is from a magma chamber deeper than 10 km. As seems to be the case.

    What everyone is worrying about at the moment are new vents as current one closes up.

    Donations buttons have returned. 🙂

    1. My concern is inflation, given the information that there is an upper magma chamber with contents, and the fractured state of the rock due to months of intense eqs then any inflation represents a danger.

      There is still high tremor recorded on sils. It is some time ago that Jon warned that subglacial eruptions were a real risk. I agree totally.

      I would add that long term eruptions can deplete magma of certain elements/compounds, and such basaltic magma can be left with a higher silica content as rhyolitic. Since the source has been open to much speculation we will have to wait and see.

      1. As to the danger of inflation and the risk of subglacial eruptions: This is exactly what Ármann Höskuldsson, volcanologist, warned about in a lecture today.

        But I never heard about a basaltic magma with higher silica content as rhyolite. What magma could that be? What is its name?

        Basaltic magma is characterised by a rather low Si content.

      2. @IngeB

        The process is called fractional crystallisation as in Bowens reaction series.

        During the various stages of cooling (esp over long periods) the basaltic magma gives up its magnesium and iron and at each phase the remaining silica % increases.

        That’s assuming the magma is coming from a single deep chamber.

      4. Inge, I know there has been much said by many people, but I try to make a point of reading everyone’s posts.

        I have for some time speculated that the holuhraun would recede due to crystalline deposition as temp falls. This is the very process I am referring to, in action. If you google fractional crystallisation there are many deeper uni articles.

        When the event started, temps of 1150C were cited. This was high enough to entrap decompression melt of some country rock, but not high enough for others. Crystalline deposition had to be occurring right from the start, a kind of push me, pull you scenario. Eventually deposition wins. Its taken longer than I thought.

        However, as I pointed out earlier there is magma in chambers at higher altitude and something has the pressure to keep it there. If the same deep source feeds both bb and holuhraun, then it could be richer in silica by now.

        All guess work and we shall see over time.

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