Posted on by Jón Frímann

Friday update on Bárðarbunga volcano 26-September-2014

This is the Friday 26-September-2014 update on Bárðarbunga volcano. This information is going to get outdated quickly.

Current status in Bárðarbunga volcano at 20:31 UTC

  • Largest earthquake today had the magnitude 5,2, it happened at 16:49 UTC. Second largest earthquake today took place at 18:54 UTC and had the magnitude of 4,3. There have so far been fewer larger earthquakes today than in last days.
  • The caldera dropped 30cm in the magnitude 5,2 earthquake. The caldera continues to drop around 50cm/day according to GPS measurements. Total caldera drop is now around 29 meters.
  • Smaller earthquakes have been taking place in Bárðarbunga volcano. This means the drop is continuing during those earthquakes.
  • Magma continues to flow into Bárðarbunga volcano around the same rate as before. This can be seen on GPS data on nearby GPS monitoring stations. For GPS information please check University of Iceland GPS information page here.
  • Bad sandstorm was in Holuhraun today. It was so bad that it was only possible to see 50 – 100 meters in front of people according to Rúv news earlier today.
  • The eruption in Holuhraun continues in the same manner today as yesterday. The lava field is now larger than 40 square kilometres. What the exact size is I don’t know since it is not known today due to weather.
  • Earthquake activity continues under the dyke and that suggests the pressure is increasing in it.
  • Currently there is no eruption under the glacier. If it was it would be visible on SIL stations around Vatnajökull glacier.
  • Nothing more has happened in Bárðarbunga volcano today far as I know. That might change without warning.
  • Storms are expected to take place in Iceland all weekend. There is going to be around three or four storms taking place this weekend with strong winds up to 20m/s and it can go up to 40m/s in wind gusts. This is going to effect SIL stations and my geophones as the storms pass over parts of Iceland.

Current status Saturday 27-September-2014 at 20:30 UTC

  • No major change has taken place today in the eruption in Holuhraun. There is also no sign that is ending. Most of the eruption takes place in one crater at the moment. New fissures might open up without warning in the area where the dyke is located.
  • Bárðarbunga caldera continues to drop around 50cm/day.
  • Largest earthquake today so far is a magnitude 5,2 that took place at 19:31 UTC. Second largest earthquake today was at 02:00 and had the magnitude of 5,0.
  • Due to snowstorm there is almost no visibility to the eruption area in Holuhraun. For the people in the field the visibility today was reported to be 50 to 100 meters.
  • There has been a lot of smaller earthquakes taking place in Bárðarbunga volcano. Some of those earthquakes are taking place due to caldera subsiding. Some of those earthquakes are taking place because the magma inside Bárðarbunga volcano is looking for a new pathway up the surface. It either has not found it or does not have the pressure yet to go up the crust yet.
  • There is less activity today in the dyke. There is however worrying earthquake activity in the dyke at the start of Dyngjujökull glacier. It might mean that magma is trying to get up to the surface. There already have been eruptions under the glacier in this area without any earthquake activity before they started. All of those eruptions lasted for a short period of time.
  • Nothing else is to report so far today (27-September-2014).

Update Sunday 28-September-2014 at 17:17 UTC

  • Largest earthquake today took place at 12:34 UTC. Other earthquakes have been smaller today.
  • Bárðarbunga caldera has dropped 7,4 meter since 12-September-2014 according to GPS measurements in the centre of the caldera. That GPS data can be found here.
  • The lava field is now 44,5 square kilometres wide. It is now larger than Mývatn (around 40 square kilometres wide) for comparison.
  • Harmonic tremor suggest that pressure is increasing in the Bárðarbungu volcano magma chamber. It drops once the magma finds way out, then it starts building up again.
  • No other information have been released today. Other activity is the same as for the past few days.

Storm notice!

Three bad storms are expected in Iceland in next few days. In parts of Iceland wind is expected to go up to 50m/s in wind gusts. This is going to effect all earthquake recording and monitoring of Bárðarbunga volcano.

Next update

Next update is going to be on Monday 28-September-2014. I wish everyone a good weekend.

Article updated at 20:31 UTC on 27-September-2014
Article updated at 17:17 UTC on 28-September-2014

447 Replies to “Friday update on Bárðarbunga volcano 26-September-2014”

  1. @wial see:

    “Earthquake activity continues under the dyke and that suggests the pressure is increasing in it.
    Currently there is no eruption under the glacier. If it was it would be visible on SIL stations around Vatnajökull glacier.”

    Who are you calling a troll? Yourself?

    2. For any future reference. An eruption under a glacier where explosive activity is taking place looks like this on SIL stations. This is Grímsfjall volcano eruption in May 2011. The largest eruption in that volcano in 140 years. It made a volcano ash cloud that did go up to 20 km high up in the atmosphere.

      http://icelandgeology.net/?p=960

    3. Any significant eruption under the glacier outside of the caldera would be obvious fairly quickly. The ice is much thinner, we topology is such that the water would run out under the glacier and we would see evidence in the form of an increased water flow. Some very small eruptions might happen under the glacier and no result in enough additional flow to be noticed, but I think we can say with safety that there is no significant eruption outside of the caldera under the glacier.

      Inside the caldera is a different story as the ice is much thicker and there is no path for water to run off. We wouldn’t notice a small eruption there at all, most likely.

  2. Magma draining from Barðarbunga caldera by gravity flow to feed the Holuhraun eruption VERSUS magma for Holuhraun eruption being derived from a deep source.

    Can these seemingly competing descriptions be reconciled?

    1. Why would it be “gravity flow”? The caldera is deep underground. From wherever it is flowing, it is rising.

    2. Its reconciled if there are two chambers. One high, one low. The low isnt as near as gassy as the first couple. But its still sinking into WHAT?

  3. well, this changes things,

    Univ. of Iceland @uni_iceland · 7h

    Measurements of #Holuhraun eruption plume suggest it’s 80-85% H2O, ~10% SO2 and only ~5% CO2 #Bardarbunga

    I am personally going with a dome building event in the NE corner now.

    Thanks for pointing out the steam re-condensation idea, hadn’t thought of that.
    There are 2 sub-glacial lakes under the icecap, but is possible one already emptied into Grimsvotten crater lake.

    (are the captchas in icelandic now too ? sheesh)

    1. Do you know this guy?

      http://www.es.lancs.ac.uk/people/hught/hugh.html

      “Glaciers and ice sheets on many active volcanoes are rapidly receding. There is compelling evidence that melting of ice during the last deglaciation triggered a dramatic acceleration in volcanic activity. Will melting of ice this century, which is associated with climate change, similarly affect volcanic activity and associated hazards? This paper provides a critical overview of the evidence that current melting of ice will increase the frequency or size of hazardous volcanic eruptions. Many aspects of the link between ice recession and accelerated volcanic activity remain poorly understood. Key questions include how rapidly volcanic systems react to melting of ice, whether volcanoes are sensitive to small changes in ice thickness and how recession of ice affects the generation, storage and eruption of magma at stratovolcanoes. A greater frequency of collapse events at glaciated stratovolcanoes can be expected in the near future, and there is strong potential for positive feedbacks between melting of ice and enhanced volcanism.”
      from: http://rsta.royalsocietypublishing.org/content/368/1919/2535

      The glacier is weakening from what I can see in the graphs, last time I checked Bardarbunga was a stratovolcano.

      This is a quote from your link:
      “Ice sheets are heavy. Each year, Antarctica’s loses around 40 billion metric tons. They are so heavy, in fact, that as they grow, they cause the Earth’s crust to bend – like a plank of wood when placed under weight. The corollary of this is that, when an ice sheet melts, and its mass is removed, the crust springs back. This upward flexing can lead to a drop in stress in the underlying rocks, which, the theory goes, makes it easier for magma to reach the surface and feed volcanic eruptions.”

      1. The relationship between volcano height, climate and glacier cap is intimite. Change the volcano height or temperature or precipitation and there is a change of state between no glacier and thick ice cap. In the past both more and less volcanoes had icecaps. We are in an inbetween period (I like Andy’s chaotic explanation)

        If there was some overall positive feedback it would be quite evident in the geological record as to eruption rates , volcano height and style. Glaciers grow and shrink so easily with changing climate

      2. Antarctica is at currently at the highest ice level ever recorded, so their statement of loses of around 40 billion tonnes of ice a year throws the whole conjecture into doubt.

    3. Phew, I’m not as crazy as I thought re the tides and glaciers. And if deglaciation causes eruptions, and Vatna is one of the last glaciers to go, and it’s going increasingly fast, we can expect some fireworks in the years to come — maybe enough, ironically, to cool the planet for a while. It’s not all positive feedback, after all. (Another negative feedback is the fate of the boreal black spruce forests — they’re being pushed north but soon will run out of land, while the southern trees replacing them are much more reflective of sunlight — although to be sure this is far outweighed by positive feedbacks like how much darker melted water is than snow and ice, let alone the permafrost and clathrate methane — but I digress).

      1. … But I digress

        and also forget there have been fireworks, a plenty in the years gone by. 🙂

  5. Receding glaciers did cause the laacher see caldera eruption in germany 12900 years ago. However back at bardabunga i think that the combination of spreading plate boundary and hotspot makes it pretty pretty insensitive to climate. The ice thickness on bb hasnt changed that much. Please stay on topic. Climate discussions about immesurable massively chaotic
    poorly understood systems with emotive topics that cannot be proved or disproved belong elsewhere.

    2. The climate isn’t the problem in this case, the integrity of the glacier is, look at the stress it has been under: http://en.vedur.is/earthquakes-and-volcanism/articles/nr/2971

      (the demo shows enough if the 3D model doesn’t run)

      The problem is that the glacier has been weakened, not by climate in this case but by the earthquakes. There are reports of cracks and the GPS movements proof that there is space for movement.

      “Bardarbunga volcano is buried under an ice cap 1,310 to 1,970 feet (400 to 600 m) thick. Three circular crevasses, described as ice cauldrons, were discovered in the ice cap during a reconnaissance flight Aug. 27, the Met Office said. Each pit is about 32 to 50 feet (10 to 15 m) deep. The pits indicate either an eruption or geothermal heating that is melting ice deep below the glacier’s surface, according to the Met Office.

      Scientists can only detect a subglacial eruption at Bardarbunga by watching for melting and “listening” for the seismic signals of lava melting ice.”

      from: http://www.livescience.com/47632-iceland-volcano-new-eruption.html

      Yes there is a lot of ice on top of Bardarbunga, but even the Met Office recognizes the fact that the glacier is under stress and is monitoring.
      This isn’t just climate or emotive in this case.
      There is a correlation between glaciers and volcanoes.

    3. Actually the ice thickness is changing to a measurable and increasing extent and we know the shield volcanos in the region formed as a consequence of the end of the last glaciation in a way in which fissures also played an essential role, so it really isn’t irrelevant to the topic, in general.

      However, I agree, we do need to keep such discussions to a minimum because as you say they can be very emotive in a non-helpful way.

      Here though http://eaadamic.wordpress.com/2013/04/28/icelands-glaciers-responses-to-a-warming-climate/ is a well-researched blog entry/paper with illustrations discussing the melt of the Vatnajökull glacier. E.g. “Because of the high amount of ice mass stored at low elevations in Vatnajökull, this ice cap is sensitive to even small changes in temperature.” Just looking at the tongue of Dyngjujökull (visible in the background of the mila cams) on maps, it’s pretty obvious it’s receded a sizeable distance in recent times. Weight is shifting. That does matter. Whether it has any particular predictive value is another question.

      And now I’ll try to shut up about it yet again.

      1. Any glacier is sensitive to change in height temperature precipitation and particulates. They are inherently unstable, either growing or shrinking. That’s the nature of the beast.

        For Iceland the glaciers are probably critically dependent on the gulfstream and percipitation patterns. You are less (or maybe more?) likely to predict how those might change in the future

        Regarding Barðarbunga, would be nice to see a new subsurface radar profile and also a surface height profile. The caldera is a big place. Not sure the single gps sample point gives a representative value

    4. I read a paper a while back that when the glaciers built up on the land, as they pressed down on the crust, it caused some relocation of magma in the mantle. It would be sort of like squeezing one side of a water balloon and it causes the water to relocate and when the pressure is released, it rebounds.

      So as the ice sheets built up, it caused an activation of some volcanic systems farther south and as the ice sheets retreated, those systems again became dormant as everything moved back north again.

      1. .7 km of ice on top of a caldera lid which is 25(?) km across.

        Less than 70 meter of subsidence so far for the rocky caldera lid which is 25,000 meters in width. That 70 meters subsidence represents 10% of the covering ice thickness. (Moving down in unison with the rock cap)

        Hard for me to imagine what will or won’t happen. Hard to concptualize what’s going on with the caldera and lava lakes at Kilaueau

  6. Thanks again Jon for your indispensable updates and all your hard work. have a good weekend.

  7. “Measurements of #Holuhraun eruption plume suggest it’s 80-85% H2O”

    Interesting.

    “Thanks for pointing out the steam re-condensation idea”

    Yeah, there’s almost no way to push steam through over half a kilometer of ice. It is going to condense back to water long before it makes it to the surface unless there is a very, very deep crack that goes nearly all the way from surface to bottom, which is not all that likely. Such a crack would probably collapse on itself first decent sized quake.

  8. I am seeing harmonic tremor signal that suggests an eruption has started under the glacier. So far it doesn’t look as this is a large eruption at the moment. I am also waiting confirmation on this from the news.

  9. A mechanism by which the subsidence at Barðarbunga feeds Holuhraun with magma which comes from greater than 10 km depth is to have both locations connected to a common magma chamber of greater than 10 km depth. Thus bardarbunga’s gravity flow subsidence is pushing magma residing at greater than 10 km depth to the surface at Holuhraun. Is that crazy or not?

    1. That is the scenario I had initially suspected but then I realized it could not be true. The scenario was a reservoir of magma with a conduit up to the caldera “plug” acting almost as a piston. The reservoir breaks another exit into the dike, pressure reduces and the “piston” (caldera plug) drops. But that can not be what is happening. While the GPS on the ice inside the caldera is reporting deflation, all other GPS units around the mountain in which the caldera is located is showing inflation. In other words, the broader evidence is that the area is still inflating from magma intrusion. Secondly, the dike appears to be expanding at a greater rate than it is erupting indicating even more magma being introduced. Thirdly, there appears to possibly be another dike formed or forming trending northwest the caldera. If the pressure inside the caldera were reducing, the probability of breaking out to form a new dike to the northwest would be reduced.

      Indications are that overall in the entire system we have new magma intrusion. The overall area of the entire glacier is inflating. We have a lot of earthquakes of significant size under the caldera. The surface of the ice directly above those quakes is dropping.

      The system is very complex, the location is unique in its particular configuration, and it has a history of extremely large eruptions in a short period of time.

      But I still say we do not know with certainty what the surface of the caldera itself is doing, we know only what the surface of the ice is doing. We don’t even know how much water there is between the bottom of the ice of the glacier and the surface of the caldera. There might be 50 meters of water, 100 meters of water, or 10 centimeters of water, we just don’t know.

      1. If magma is present, the caldera cannot drop. Ever.
        Watch the magma, this is not an explosive event. It is worse.

      2. I pretty much agree. A conventional caldera collapse occurs only after rapid emptying of the magma chamber. We have not seen that. The caldera formed at Askja after the 1875 eruption there is over 200 meters deep and the subsidence continues today.

        One correction, the bottom of the caldera is under about 850 meters of ice, not 700. The caldera itself is about 700 meters deep with another 150 meters of ice packed above the rim of it. I think it is unlikely that it is ice all the way to the bottom of the caldera. It is likely water at the very bottom due to geothermal heat but how much, I don’t believe anyone knows because I don’t think anyone has drilled into it to find out.

        Askja caldera is a lake as it is not high enough in altitude to remain frozen year-round (Iceland’s second largest lake). It isn’t unlikely that the caldera of Bárðarbunga is a subglacial lake.

      3. Why the sag in the middle of the caldera? If it is water, it has to drain somewhere. Otherwise the ice above would float.

    2. No, it doesn’t have to drain at all. It is in a bowl. If what I think is happening is happening the sag in the ice is due to it melting from the bottom. The water level isn’t high enough to float the ice.

  11. I actually do not believe that there may be 700 meters ice on it lie.
    how cold the surface is. it would not surprise me if there are only 50 meters of ice it is. and why? love about those geothermal.
    Caves in Netherlands how deep so too are definitely lower than 8 degrees.

  18. We are seeing very rapid decline now. I wonder if we are seeing heavy rain there. That can cause rapid glacial ablation.

      1. It’s too high up (around 2000 m) and northerly to be rain at this time of year. There was new snow eg. near the Kverkfjöll webcam yesterday, and it is not on the top of the mountain.

  21. The radar would detect any water/ ice boundary, thats how all sub glacial lakes have been detected. No one is reporting water in the caldera. The long time plot since sep. 12th of gps measured subsidence shows remarkable linearity. Any change to this will be significant.

    1. Limited budget. Only one (public ?) GPS site across a large caldera. Be nice to see a new surface scan and ground penetrating radar profile

      1. Even now it was something difficult to find a place for the GPS, because there are no icefree nunataks on this mountain. And the weather there during the winter time is fierce, so a GPS station they place there is very difficult to service and always in danger to get lost in storms and esp. snow storms. Even without an impending / rather well possible eruption at the place, the stations would be endangered. And the money lost.

    2. Where does all of that steam that is venting through the Holuhraun fissure come from? Only one possibility – vaporized meltwater from the glacier inside the Bardabunga cauldron.

      1. I would suppose, it is groundwater and water inclosed in the magma (otherwise it couldn’t flow).

      2. See eg. for water (H2O) in rhyolitic magma bodies:
        http://onlinelibrary.wiley.com/doi/10.1029/1999JB900207/pdf

        Generally: “Dissolved H2O in the silicate liquid portion of magmas is one of the most influential components of igneous systems. It affects the density, viscosity, and the phase equi-
        libria of these systems.” http://minsocam.org/MSA/AmMin/toc/Articles_Free/1998/Moore_p36-42_98.pdf

        Which I would translate into :
        The water is part of the magma (and the magma to be imagined more or less as a sort of liquid and a mixture of different elements, ao. water – the honey, Haraldur Sigurdsson mentioned http://vulkan.blog.is/blog/vulkan/entry/1443833/ ). And it is even a very important part of it, because it influences am. the viscosity, i.e. if this specific magma is more like honey or more like peanut butter) and the phase equilibia, ie. if it is more fluid or gaseous. And therefore of course also the explosivity. Fluid magma -> effusive eruptions (lava), gaseous magma -> explosive eruptions.

        In the whole: Most of the water degassing in this case is included in the magma when it mounts from depth. At this point, the melting water just plays a role with cooling the borders of the lava field, as the headwater streams of the river Jökulsá á Fjöllum hit the lava field. And perhaps some small portion of it is percolating down through these lots of fissures one sees on the pictures and is hitting the ascending magma. But that can’t be much, because otherwise we would have steam explosions.

  22. If the GPS reading indicate the larger area is inflating, yet the ice above the caldera is subsiding, and nobody can see if the caldera floor is itself actually subsiding.
    Then to my (uninformed) mind the first thing that comes to mind is of course that the ice may be melting below. Ice takes about 9% more volume than water. So if there’s a subsidence then this could correspond to about the volume of the subsidence divided by 9 times 109, and the answer is how much ice would have to melt to lose that amount of volume.
    My guess is that it’s not that much as the subsidence of the ice is not 29 meters across the whole area but only at its point of greatest subsidence (and no subsidence at the edge / ridge of the caldera?). Rough guess less than 100 meters of ice at the bottom of the whole caldera (very rough guess as I don’t know the dimensions involved of the volume of subsidence nor the area of the caldera floor).

    Is the above scenario a possibility? Or is there compelling evidence that this cannot be the case?

    Sorry if this has been asked and replied to before, but I have not read nearly all the comments past weeks.

    1. Yes this idea has been posed many times. It’s an ongoing debate but two big points to keep in mind: 1) the shape of the earthquakes as measured by multiple sensors indicate subsidence of the rock itself, all around the caldera rim. 2) ground-penetrating radar from plane overpasses repeatedly confirms this.

      If there’s data indicating the ice is melting over the caldera lid, I haven’t seen it (which doesn’t mean much). The ice is already as compressed as it’s going to be, so it’s not a matter of it settling due to the earthquakes, either.

      Now, somewhere near the magma chamber rock is swelling and shrinking due to changes in heat. It could even be swelling but sliding down faster than it swells. It could be shrinking as magma vacates down dikes. I haven’t seen much discussion about that, but it’s got to be a salient factor and perhaps we can make educated guesses as to what’s happening in that regard.

      1. “2) ground-penetrating radar from plane overpasses repeatedly confirms this.”

        That is inaccurate. There has been no ground penetrating radar of the actual caldera itself that has viewed deep enough to see the bottom. The only radar imaging so far has shown the ground through the glacier OUTSIDE the caldera where it is much thinner . The radar images I have seen that include the caldera do not show all the way through to the surface, they show only a flat surface some several hundred meters deep. The bottom of the caldera is about 850 meters under the top of the ice.

  23. I hope there is a bug, because at 6h00 the GPS says the caldera drop -1,5m in few minutes 8-/

      1. Are you sure? I don’t know how to read the charts very well, but several sites are reporting a 4.8 at 2:0015 UTF 64.66N 17.68W. Is it an error in reporting?

      3. Ok, it’s probably a ‘bug’ of GPS system in this place.
        I suppose it when i saw the drop, but not sure of course, thanks

  24. “The radar would detect any water/ ice boundary, thats how all sub glacial lakes have been detected. No one is reporting water in the caldera. ”

    Nobody has shown any pictures of the caldera itself that I have seen, only of the glacier outside the caldera. The glacier is MUCH larger than the caldera. Not sure the radar they are using can penetrate nearly a kilometer.

      1. Ah thank you Crosspatch these graphics are excellent especially the second one for me. Now I understand when you discuss about the rim of the caldera and where the earthquakes are placed and the dyke. I am learning so much from Jon and you guys here.

  25. This is sketchy, not Iceland, and is all the information I have:

    NHK Japan reporting volcanic eruption with injuries to people. That’s all I have right now.

      2. Looks like it came as a total surprise . They raised the warning level from 1-3 out of 5 after the eruption…I think. From the looks of the video it is mostly Phreatic .

  27. Don’t get hung up on the latest GPS readings again. This keeps occuring here and it’s been discussed time & again that latest readings are subject to errors, which is why averaging periods are used to correct these and you should ONLY be looking at the trend line in Blue (the 3 hour average) for any sense of accuracy. Most of the 1M drop the GPS was showing has recivered on latest readings – and the mountain definitely didn’t drop a metre and rise a metre an hour later. We’d know about it if it did!

  28. Just getting a little view on Mila cam 1 – looks like there has been a dusting of snow overnight?

  29. Thankyou IngeB you seem to know a thing or three. So sticking to what can actually be measured observed and simply explained we have EQs that whos vibration movement couples show fault slippage rather than explosions. Also the long period vertical GPS is remarkably linear reminiscent of school exam questions of containers filled by some pipes at different rates and emptied by other pipes at other rates. That the container might vary in size or others might appear was never in the exam questions luckily.

  30. Just getting a little view on Mila cam 1 – it looks like there has been a light dusting of snow overnight?

  31. crosspatch

    An excellent post by you at 21.15 on the 25th Sept

    I believe the caldera is rifting and the whole volcanic plug is dropping. This I suggest is scientifically supported by the distribution of the eartquakes around the contact of the plug with the wall of the vent. It can be seen that the distribution of earthquakes is greater in the NNW and SSE (or there abouts) of the plug. For me this suggests that the vent wall is getting pulled at these points either side of the plug and that the rifting of the crater is occuring from the SNE to the NSW. I think of it as a wine cork held in a nut cracker, as I slowly release the pressure on the handles of the cracker, the cork slowly comes away from the sides and then drops. So this type of caldera collapse is quite unusual, in that :

    1) the caldera collapse is into an active and sometimes inflated magma chamber.
    2)The weight of this substantial core is being partially supported by the pressures from below.

    I believe the collapse will occur immediatly after the widening of the rift along the fissure. If I am correct it would make sense if a new fissure eruption occured SNE and outside of the crater just before the caldera collapse or during it. As the rift ruptures with the release of energy. I expect a very large earthquake (7 or greater) from the rift at the moment of the caldera collapse.

    It is made complex by the offset of the rift in the vicinty of the volcano, hence the line of the rift is not the same as the current fissure event.

    As for the impact of such a collapse, I don’t know. Are there any historic or geolgically historic eruptions produced by the collapse of a volcanic plug into an active full volcanic chamber fed by a mantle plume?

    I am expecting at least a VEI6 and more likely a VEI8 because of the contained mass of the volcanic plug. I hope it just stops! If it happens and help is requested from Iceland, I am sure the UK and Europe will do all they can for the people of Iceland. If it’s a VEI8 the whole of NW Europe will need help.

    1. Bárðarbunga has never had a VEI bigger than 6, so it is not probable that this will be such catastrophic.

      1. It never happens until it happens. There is always a first time. So yes, the track record of Bardabunga reduces the statistical probability of a VEI6+ eruption, but it does not exclude it.

      2. While I do not like the doomers, Bardarbunga is a very young volcano that gives every indication of having a very large magma chamber. It also has a buddy a few dozen kilometers away that has multiple caldera formations on record and probably the largest hot magma chamber on the planet.

        As I would consider the distinction between a “middling” VEI 6 and any VEI 7 that has actually happened to be fairly minor, this is not something to denigrate.

      3. Yeah in a way, the Vatna system is like a supercomputer. BB is just one big core, but historically (Laki), Vatna can do a lot of “parallel processing”. Any one volcano or fissure is not that big compared with a supervolcano like Yellowstone, but get a few of them going together, along with multiple fissure swarms, and you’ve got something out of science fiction.

        Odds are very low of this happening, though, even if BB has a full scale caldera collapse eruption.

    2. VEI-8 lol. just lol. You would need a LOT more force, orders of magnitude more. VEI-6 might happen, or it might not. The caldera could completely collapse and never even once erupt in the caldera.

      or it could start an eruption in the caldera tomarrow. *shrug* what happens, happens, but there’s just not enough force to provide for a VEI -7 or 8. if there was enough force for that, the caldera woulde be inflating, not deflating. yes deflation could trigger a large eruption. but the fact that it IS deflating is certain to put an upper limit on the force involved. Work out the cubic km of the volcanic plug of the caldera floor, and remember that there is NOT enough pressure to even keep that up, let alone eject far more massive amounts of magma.

      1. StridAst, your arguing in a closed system. What will transpire over time in between the entire mantle and Lithosphere is in fact unpredictable. A further acceleration in plate separation and magma finding new pathways of intrusion from depth would change the whole equation. Even in your closed system argument, you have no way of knowing what is going on down there. All is speculation so to assert definitively is to eventually be proven wrong. This eruption could develop into a VEI9 if it wanted to. I personally think this eruption will not be isolated the current fissure and caldera but will expand to the SW of BB. A VEI8+ is the more likely scenario in my mind, which doesn’t need to rely on science to see.

      2. A VEI-8 would be the largest eruption ever recorded (discovered) in the last many tens of thousands of years.
        Even the mere chance of it happening is *very low*.
        The most probable outcome of this eruption, in terms of VEI, is a 4-5 level.
        Even a VEI-6 I believe has very low probability, let alone 7 or 8.
        The Great Laki eruption of 1783 was a VEI-6,
        https://www.youtube.com/watch?v=LeDYtj1TYOk
        it changed the climate in the entire world for many months, like Pinatubo did in 1991.
        I could be wrong, but at this moment I don’t see Bardarbunga developing into a large eruption like Laki in 1783.

      3. I really loled hard there. VEI9. lmao as if there has ever been a single known VEI9 At least on earth. The current largest known explosive eruption on earth is Wah Wah Springs. (it’s here in utah where I live) Eruptions of the various Traps don’t count, considering they are effusive and not explosive. therefore, vei-0 much like the current eruption going on from BB.

        You are right, you don’t need to rely on science to see what you are seeing 😀 considering science doesn’t exactly allow you to see that. Well, perhaps chemistry allows you to see it, or perhaps biology 😀 Those are both sciences after all….

      1. Volcanologist Ármann Höskuldsson said in a discussion with district representatives in East Iceland ( http://www.visir.is/bardarbunga-gaeti-taemt-sig-a-solarhring/article/2014709279923 ) , that the biggest eruption possible in Bárdarbunga would be over in 1-2 days. He compares it to Pinatubo in 1991 (a VEI 6 http://www.volcano.si.edu/volcano.cfm?vn=273083 ). The eruption column then could reach a height of about 30 km and the jökulhlaup in the river Jökulsá á Fjöllum would be 250 m3/sec. x 40 (= 10.000 m3/sec). [I think that is not enough, even Gjálp in 1996 produced more, up to 45.000 m3/sec]

        He says that this explosive eruption would come from a shallow magma chamber which would be emptied rather fast. The eruption in Holuhraun could on the other hand still continue afterwards. He argues that the latter would be possible, because this lava comes from a deeper source.

      1. reality would not allow for any conjecture.

        The thought police have never been able to contain thought, idea’s, intuition, etc

  32. There is a heat source, and glacier ice, eventually water.
    Still no evidence for a subglacial lake ?
    Melt water – if there is any – would be captured between rocks and a thick glacier.

    I am wondering whether some kind of steam-powered “fracking” is impossible (oscillating steam pressure, re-condensation was already mentioned).
    Probably these thoughts are not new, however, which tremor plots etc. could be expected in that case ?

    1. There’s enormous heat under all of us, fed by a combination of gravity and billions of years of slow dirty bomb radioactivity, but we don’t feel it unless we’re in a hot spring or some such. Calderas do melt ice and turn it into lakes, it happened just recently in Iceland, but I’m still waiting for someone to tell me it’s happened in BB’s caldera. Likely it will, at some point, and then, yes, god’s espresso machine will go to work on the water in the magma and the ice, fracking that stuff so fine it becomes volcanic ash. A frackuccino, if you will.

      2. I may have overstated the case, but Askja.

        http://en.wikipedia.org/wiki/Askja

        “In early April 2012 it was noted that the lake in the caldera was totally clear of ice, which usually does not happen until in June or July in a normal year. It is believed that increased geothermal activity in the volcano is heating the lake. Travel in the area was restricted until further research could be carried out. [4]”

  33. Quite an impressive inflation from GPS at Bardarbunga, approximately 30 cm which has just tapered off in last hour.

    The status quo continues Mantle Versus Gravity. The upper crust has sustained enormous pressure from both directions. A new overflight video of the area would be interesting to see new stress fractures in the ground surface. (if anyone has one to post/link please).

    1. Yes, and based on previous patterns, we can almost predict with certainty that a 5+ quake is going to come along in the next 1 to 3 hours. I too really want to see if there is more surface evidence of cracks in the ice. We might have to wait until visibility is a bit better.

      1. Journalist Ómar Ragnarsson says on his own blog that he flew over the site yesterday and intends to set pictures on the net. http://omarragnarsson.blog.is/blog/omarragnarsson/entry/1452463/ Could be that he does it via RÚV.

        He compares the area with a battle field …

        Today snow is covering the area partially (see webcams). RÚV even reports (Icelandic) that the scientists don’t see a thing at their hut near Askja because of snowstorms and intend to have their operating center from tomorrow on at Mývatn because of the weather.

  34. Volcanic eruptions of VEI more than 6 normally occur at subduction zones (convergent plate boundaries) or hotspots under thick continental crust (Yellowstone) with very viscous magma. Iceland lies on a spreading plate boundary where very fluid basaltic magma is the main eruptive product. We should not be frightening people with irresponsible talk of VEI8s.

    Glacier ice is only brittle (able to crack) near the surface. At depth, under great hydrostatic pressure, it flows, slowly but orders of magnitude faster than the mantle flow that gives rise to isostatic uplift. This is why drillholes in ice close up quite fast unless they are filled with drilling fluid. There may well be meltwater under the ice in the caldera, but rather than forming a lake it could be doing surprising things like flowing uphill under the overburden pressure of the ice (which many glacial meltstreams do) or seeping out through the fractured caldera walls.

    The standard technique for measuring the thickness of glacier ice, airborne radioechosounding, is tuned to penetrate km of ice, as in Greenland and Antarctica. This is how the bedrock surfaces have been mapped and how subglacial lakes under the Antarctic like Lake Vostok and Lake Ellsworth were discovered. If there is a significant body of water now at the base of the ice in the caldera, the next scientific overflight will see it and will be able to map it from the pattern of reflectors on their charts. Someone recently posted the URL for the bedrock crossprofiles measured so far (yesterday?).

      1. What you see in the foreground is Kverkfjöll and as this is another active and big volcanic system, there are often some fumaroles active there.

      2. No, of course it’s kverkfjoll, but what i was talking about and i can’t see now was two small vents in the line of the active Holuhraun fissure eruption.

    2. I think you meant the picture at 13.10h. There are some clouds that drifted away…but you can look back in the time if it was another one…

  37. I’m not convinced the GPS readings showing the huge drop then inflation are real.

    We know it’s snowed – can see it on the cams. We know snow affects the signal. We can see the errors on the chart (the big spikes).

    I suggest maybe a layer of snow settled on the antenna and has since thawed.

    Where are the quakes associated with all this movement? It seems highly unlikely a 10km * 4km * 2km slab of rock can move this much without making some sort of noise.

    I’m not saying there hasn’t been any movement at all – we think there has previously been inflation events, just that it’s not likely there has been the amount of movement the chart is showing.

    1. I have read that Vonaskard sil/gps is being used as a reference point for the gps on B. I think the figures are accurate. However I have also read that the larger area as a whole is inflating. There is just so much going on and as Jon points out the pressure is building as more magma is coming in than is going out at Holurhaun.

      We all know its a watch wait and see, even for the IMO top brass. I think for the record we should write down our personal views of the unfolding of events and see if we are close when it happens. I do have a bleak outlook for this myself and although I have recorded my opinions rigidly I pray I am totally wrong. It would not be good for Iceland or the wider area.

      1. That’s fair comment. But ignoring the drop, there’s a pretty flat line on the graph – no net loss, no net gain – and I’d say that was more likely than the thing inflating and deflating over a couple of hours.

        If there is THAT much Magma rising below this system, then not only does Iceland have a potentially huge problem, but most of Europe has too – and I just don’t think this is going to lead to anything that big.

  38. Any recent update on the fissure eventually affecting Askja? I read about the explosive effect of the basalt in the intrusion intersecting cooling rhyolite crystal mush and I was curious about what the experts think

      1. Much less of one, but I remember reading something about the dike hitting a wall of hard granite blocking its access to Askja before it came up at Holuhraun. And I’ve seen it said the earthquakes NE of Askja were happening before all this started in August, even if they do appear to have some linear relationship to the new dike and might be affected by all the shifting and disturbance going on.

    2. There is no granite to be found in Iceland, except for one single location, not anywhere near Askja. It´s all softer rock.

      1. Actually “granitic” basalt does seem to exist around Askja, or so the following article claims, with citations. Whether “granitic” is granite is another question.

        http://www.dailykos.com/story/2014/08/25/1324426/-40km-Long-Fissure-Is-Ripping-into-Violent-Askja-Linking-Iceland-s-3-Largest-Volcanoes

        “But that’s not what concerns me. I’m concerned about Askja. There’s something about Askja that makes it more violent than Bárðarbunga. Iceland is the only place on earth where a mid-ocean ridge, a hotspot and granitic rock come together and the place where they come together is Askja. Unlike other mid-ocean islands Iceland has a thick crust in the central region because the hot spot is captured on the ridge and they rate of lava production has been high relative to the spreading rate.
        Thickness of Iceland’s crust.attribution: https://community.dur.ac.uk/g.r.foulger/Offprints/OlderCrust.pdf
        The crust of central Iceland is twice as thick as normal oceanic crust.
        This thickened crust has pushed down basalt to depth and the basalt has partially melted to produce granitic intrusions at depth.And that makes for trouble at Askja. The world’s most violent volcanoes are located at continental hotspots where basaltic magma interacts with granitic rocks. Yellowstone, Wyoming; Valles Caldera, New Mexico; and Long Valley California are 3 explosive volcanic systems that produced catastrophic eruptions when injections of mantle basalt melted granitic rock.”

        I think I learned about it right here though: http://icelandgeology.net/?p=4789

  39. Is that water building up just the corner right of the screen on Mila 1. Just thinking it could be a start of a new lake caused by the lava field blocking it’s flow. or is it just a light snow covering.

  41. Wow, for a minute there I thought we had new activity on the glacier over by Kverkfjoll. Looked just like a steam plume. But we have cold weather, and warm water and lava field producing that as the cold air moves over. Those clouds are not over the glacier.

      1. We can see in Kverkfjoll cam too. This is not a cloud! it came from ground and moves fast!

      3. I think we’re talking 2 different things here. Cam1 showing cloud feature that I’m talking about starting off the left side of cam. If your talking left side of eruption, that would be more center, center right of cam 1. I can’t really see much, but I think your talking about Kverkfjoll cam where there is a very low white cloud band starting near the eruption site. Am i right?

    2. Ok Luisport, I see what you looking at. At this point all I could say is what I said before, lava field and water producing that. And that area is really off the beaten path from the dyke itself. Hasn’t been any quakes in that area.

      2. It could be the end of the lavaflow.
        If you look here two days before in the morning, you can see the white steam from the lavaflow at the right side:
        http://brunnur.vedur.is/myndir/webcam/2014/09/24/webcam_mogt_kverkfjoll.htmlwn
        With the cold wether, the steam could form his own clouds. This morning I could the cloud at bardabungacam 1 coming from left towards the fissure…but it’s really tricky with the wether conditions and lava and highlands and dust…

      1. Most likely, not sure why though. Looking at the quake depths most are above 10km, and I didn’t see any below 15km, so from this I’m guessing it’s not a fresh influx of magma.

        Or perhaps the pathways from deep are fully opened now and this is why we don’t see the really deep quakes.

      2. Even if you could otherwise see a really deep, small quake, you won’t see it in active volcano plumbing. Too soft and too noisy.

        Today is a definite change in activity. I’m not going to make much of the subsidence since there were *massive* instrumentation issues last night, but this is different.

    2. That’s a new pattern as far as I can recall — a lot of microquakes distributed throughout, not so much in a ring. Given magma per se doesn’t cause quakes since it’s fluid, what could be causing these? As they say on the House TV show, a rash — a new symptom!

      Maybe it’s just the notorious lack of precision in 3dbulge … although quality per IMO is listed at 99 for almost all of them …

      There seems a bit more emphasis in the direction of Tungnafellsjökull. Jón has noted the new activity there previously. Maybe a dike trying to open?

      1. This is not a new symptom, it all started out like this last month.

        Magma does cause earth quakes as it heats up the surrounding rocks, cracking them and forcing it’s way through it.

      2. I would concur with the idea of general heating influx. No particular “blasting operation” is needed under the volcano itself to clear room so it will not be as intense as what was seen when the dyke was trying to cut a path all the way to Askja.

      4. @ IngeB

        If I’m reading the table right, those quakes are about 13 km East of Kistufell; right where the fissure is.

      5. Right, Peter, it is not under Kistufell, see that now.

        The dyke getting more fresh magma from a deep reservoir?

    3. Ray of hope: If tidal action has anything to do with it (I admit its very uncertain) then activity will be decreasing now. Note that the volcano in Japan was subject to the same forces. Also, the Holuhraun fissure eruption may function as a sort of pressure relief vent for Barda, making a violent eruption there less likely.

      1. It’s more a pressure relief for the dyke, not Bárdarbunga herself. It has helped to avoid a bigger eruption at the dyke and under the glacier up to now and helped to avoid that the dyke does some other not very helpful things… But this is also important.

  43. Subsidence of the caldera has been practically stopped for 18 hours, and the quakes of M >3 now concentrate on the northern part of the ridge. Can one interpret these recent changes ?

    1. I think Bardarboom did (21:14).

      Perhaps the quakes under Kistufell also have something to do with it.

    2. weak equlibrium magma press x glacier “weight”. I (only) guess that we are near bigger quake (M5,5+), which will cause a new glacier surface movement

  44. I suppose with all the big quakes that have gone on, we have quite a bit of fractured rock now. These micro-quakes are the fracturing of the bigger cracks that have formed. A solid plug that is turning to rubble down there. At some point, magma is going to reach the surface with all the pathways being created.

  46. here is the radio sounding pic, showing the sub-glacial lakes, tho it is believed one at least drained to Grimsvotten in the opening of the show

    http://tinypic.com/view.php?pic=317a24m&s=8

    the quakes around the interior surface of caldera , are from compression of the surface from a dome building on the NE caldera rim seam, i think.

    1. Might well be. We are now seeing a lot of quakes at around 1km and shallower depth. I still believe there is an eruption ongoing under that ice but we just haven’t seen any evidence of it yet and probably won’t unless it melts the entire caldera glacier. It would likely begin to spill water over the rim, though, before it melted the last 150 meters or so of it. It takes a LOT of heat to melt that much ice, though.

      3. OK another question that probably doesn’t have an answer and shouldn’t be asked: I too noticed we seem to get a lot of 5.2s in particular. Is there anything about that particular level of energy release that tells us anything about the nature of the event? And are all the 5.2s similar in mechanism and/or location?

  49. Thank you, Jón, for the update. Interesting. 🙂
    Let’s hope that the magma stays under the glacier.

    1. It’s “only” a track, but the scientists couldn’t go behind this line and from the other side it’s a long travel…

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