Eruption at Holuhraun & Bárðarbunga, Iceland

#1

It’s hard to believe that the eruption at Holuhraun is still going on, over 100 days since it started! The seismic activity has lessened a bit, but in absolute terms is still very high. The fissure eruption is still producing a lot of lava - over 77 km2 now, and by some estimates over 1 km3 has been erupted. The caldera at Bárðarbunga is still slowly collapsing, although the GPS monitor has sunk so far that it can no longer communicate with the base station so exact data is no longer being produced. I’m struggling to find out exactly how much subsidence there has been in total, but it was 42m at the beginning of November, so I’d guess 50-60m. 


The updates from the Icelandic Met Office are pretty monotonous though, “Eruption same as before”, basically! But there’s no reason to think there’s any end in sight! 


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#2

Seismic activity is decreasing


The earthquake sequence around Bárðarbunga in 2014 continues at high levels, but has shown clear signs of gradual fading during the last weeks and months. This slow decay of activity is reflected by lower magnitudes and numbers of earthquakes, seen as a general decrease of seismic moment release.

Wonder if this means that we’re going to see a fading in the eruption at Holuhraun as well. 
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#3

The Holuhraun lava field is going to get a new name, just to confuse everyone who’d got used to Holuhraun after originally calling it Bárðarbunga. 


The lava field now covers over 85 square kilometres and is Iceland’s biggest eruption for 200 years. New video shows just how impressive the lava lake is! I’ve read that the lava is now moving through closed lava tubes about 15 km, which will keep the lava nice and hot until it reaches the end of the lava tube! 

Nasa photo, via the IMO


And another satellite photo which shows Iceland in its winter coat, except for Holuhraun! 


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#4

haha that bottom pic is awesome. The weather has been wild in Iceland this winter, and that pic illustrates it beautifully.
I understand the lava fleld is already being called Nornahraun (witch’s lava) but I guess that might not stick.

Winter in Iceland can be pretty grim (certainly was when I was there) but on the plus side, the blackbirds one of my relatives gets in her garden are ravens. How cool is that? (sorry total derail…)

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#5

Yes, I’ve seen people refer to it as Nornahraun too - the argument is that there are already two Holuhrauns, so they don’t want a third, which is fair enough but they really should have thought about this months ago when it became obvious that significant lava was being erupted! Whether the locals, who will get to decide, like Nornahraun is anyone’s guess. 


Certainly, though, a few of my geologist friends a bit miffed at yet another possible name change. There’s only so many times you can change a name before it gets still. I am seeing a few people tag tweets with #bardarbunga #holuhraun #nornahraun, which is a right waste of characters! 
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#6

So is there a job I can do in Iceland, thus allowing me to move there, for a primary school teacher who speaks no Icelandic? I really wish I could move there!!

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#7

Ach learn icelandic. It’s not so hard really :slight_smile:

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#8
Ach learn icelandic. It's not so hard really :)

Ha ha ha. 


You going to give us lessons?
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#9

Æ ég bara get það ekki. Því miður.
I’m not terribly good at it. There is an online course though, that you’re kind of expected to do if you go ther to work or study.
Eta I will clarify that the fact I don’t know the grammar well enough to teach it to anyone else. I can sound like a native, but come unstuck if I have to write anything :slight_smile:

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#10

So if anyone is interested, the eruption is looking pretty cool on the webcam right now :slight_smile:

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#11

Eruption intensity is decreasing, and “markedly” so, apparently (sorry, PDF:


http://en.vedur.is/media/jar/Notes-from-surveillance-flight-to-the-eruption-site.pdf

Observations from the previous surveillance flight held on 10 JAN had already indicated that the intensity of the eruption had decreased since early DEC 2014. Observations made on 21 JAN not only confirm this, but also indicate that the intensity of the eruption has decreased (markedly) further. The collective evidence is given here below.

Vent activity and appearance:
By comparison of the below two images from 10 JAN (left) and 21 JAN (right), it is evident that the bubble bursting activity (already reduced from NOV) has reduced even more during JAN. On 10 JAN occasional larger bubble bursts still had the thrust required to send spatter outside the high southern crater wall. The northern end of the rampart remain active and the thermal erosion of the northern crater wall observed on 10 JAN has by now caused the wall to collapse and lengthen the rampart. There is still no pathway for the lava to flow directly N/NW. The level of the lava stand inside the crater is now at the lowest level since the lake first formed. 
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#12

Still going… I thought for a moment when I checked the IMO website that maybe it had stopped and I hadn’t noticed, having been a bit busy lately, but they’ve just redesigned their front page a little bit. 


It’s been over five months now, and the eruption is still going and the Barðarbunga caldera is still subsiding. They’ve managed to get GPS data from the caldera again, but subsidence does seem to have slowed a lot

There’s no reason to think that it’s going to stop any time soon, though of course, it might stop tomorrow. 



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#13

Oh, and it’s called Nornahraun now, because apparently there were already two Holuhraun in the area. Hraun means ‘lave flow’, and norn means ‘witch’ (though Luehea can correct me if I’m wrong) so Nornahraun means ‘witch’s lava flow’. 


Anyway, here’s a new photo: 



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#14

yeah, some field work!

I can indeed confirm that Nornahraun means “witch’s lava”. It’s named for the “witch’s hair” or pele’s hair that spread over the area in the early days of the eruption.

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#15

Here are some pretty pictures from the various flights over the eruption from the start to the 31st january this year

The captions are in Icelandic - the second one down reads
"Ef grannt er skoðað má sjá þyrlu við mökkinn (t.v.)" which means
"if you look closely you can see the helicopter in the smoke/steam*" You have to look pretty hard! gives you a great sense of just how big the hill has got - it rises over 40m or well over 100ft above the surrounding landscape.

*I loosely translate “mökkin” to be “murk” - not smoke or steam or fog, but kind of a mix of all three. I checked it on Google translate just to see, and it “helpfully” translates it as “Mocha”.  :-S

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#16

Nice photos! It seems that the intensity of the eruption is dying away now. On the 19th, the IMO said:


Overall assessment: The general assessment is that the intensity of the eruption continues to decrease. Now only one active vent inside the crater, lava stand inside crater continue to sink, eruption column reach no more than 1000 m above ground, all but the uppermost 2-300 m of the lava channel is crusted over.

The closed lava pathways feeding sectors of the lava field to the NE and E remain active, with the predominant mode of emplacement being by inflation. With further reduction in effusion rate, the activity along closed pathway ENE appears to be retracting westward, no longer able to sustain active breakouts by Jökulsá (17-18 km from vent).

Unless something changes, I think we’re in the closing phase of this eruption. 
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#17

I agree. And I bet the tour companies are willing it to finish soon so that the gas and ick stops in for the holiday season in May…
It’s certainly on my to do list next time we go!

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#18

The eruption has stopped!! 


http://www.livescience.com/50004-iceland-eruption-ends-bardarbunga.html

At least for now. 

The huge Holuhraun lava field is still pocked by steaming craters, but no glowing lava was seen from the air or detected by satellites on Friday (Feb. 27). Scientists with the Icelandic Meteorological Office declared an end to the six-month-long eruption on Saturday (Feb. 28).

They’ll continue to monitor it, but it will be interesting to see if the caldera at Barðarbunga stays deflated, or reinflates. Really, anything could happen. We won’t know until it does. 
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#19

Interesting look at the gas output of Bárðargbunga:

Over six months, it spewed out:

  • 11 million tonnes of sulphur dioxide
  • 6.5 million tonnes of carbon dioxide
  • 110,000 tonnes hydrogen chloride

That’s quite a lot, but not as much as Laki, and not as much carbon dioxide as human’s produce!

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