iceland Bárðarbunga and Askja - Volcanic Activity

[john pike]

Monday
22.09.2014 18:45:46 64.671 -17.479 7.3 km 4.6 99.0 4.2 km NE of Bárðarbunga

 

 

http://en.vedur.is/earthquakes-and-volcanism/earthquakes/vatnajokull/

Edited September 22, 2014 by john pike

[If Wishes made Weather]

Ah - I see it now.  Right at the depth that so many of the larger quakes have been. The tremor plots certainly are all over the place.

[john pike]

hi tim

 

its a bit hard keeping track of this at present

 

note the last 4.6 quake just showing happened at 18,45

 

nearly 3 hours ago

[john pike]

 

and another

[john pike]

Monday

22.09.2014 21:17:48 64.612 -17.480 1.1 km 1.2 90.03 3.9 km SE of Bárðarbunga Monday

22.09.2014 21:15:46 64.617 -17.478 1.1 km 2.5 90.03 3.5 km SE of Bárðarbunga Monday

22.09.2014 20:15:36 64.668 -17.400 0.8 km 1.4 90.05 6.8 km ENE of Bárðarbunga

 

http://en.vedur.is/earthquakes-and-volcanism/earthquakes/vatnajokull/#view=map

 

not checked yet though but are shallow

[john pike]

Monday

22.09.2014 21:17:48 64.616 -17.485 0.1 km 2.0 99.0 3.4 km SE of Bárðarbunga

 

thats checked and 0.1km depth

[john pike]

 

http://en.vedur.is/earthquakes-and-volcanism/earthquakes/#view=map

 

notice the gap area is going now

 

http://en.vedur.is/earthquakes-and-volcanism/earthquakes/#view=map

[john pike]

http://www.livefromiceland.is/webcams/bardarbunga-2/

 

cor thats big

[john pike]

 

and again up this goes

 

expect more quakes

 

when they show ??????

[john pike]

another quake around 11.50

 

probably around a mag 4

 

but too slow updating tonight so going to bed

 

goodnight all

[Love Snow]

Jon fr said in comments

My early maths suggest that new point of return is around 55 – 75 meters at present. I haven’t finished checking and refining my calculations yet. The caldera is going to stay up for as long there is magma below to support it. The risk is that magma is going to find a weak spot in the caldera rim and rush out with a force. This has happened in the past in other volcanoes.

[SteveB]

A 5.2 recorded at around 4.30 this morning at a depth of 4.9km

 

A couple of mid 3's as well, with one being at 0.5km

[NorthNorfolkWeather]

A 5.2 recorded at around 4.30 this morning at a depth of 4.9km

 

A couple of mid 3's as well, with one being at 0.5km

 

 

All seeming to get quite a bit shallower.

 

They quakes are still being reported late, I looked at the site about 90 mins ago and there was nothing

[SteveB]

Not sure whether it means anything, could you be down to lack of personal - someone who usually does the checking being off sick or on leave!

 

Surely something got to give soon with all these quakes, how many +5 must that be now, at least 20 since the eruption began!

[NorthNorfolkWeather]

Coming thick and fast now M3+ at least every couple of hours since midnight

 

Date Time Latitude Longitude Depth Magnitude Quality Location Tuesday
23.09.2014 07:57:20 64.671 -17.485 6.9 km 4.0 99.0 4.0 km NNE of Bárðarbunga Tuesday
23.09.2014 06:18:24 64.679 -17.462 8.0 km 3.5 99.0 5.3 km NE of Bárðarbunga Tuesday
23.09.2014 04:33:55 64.683 -17.418 4.9 km 5.2 99.0 7.1 km NE of Bárðarbunga Tuesday
23.09.2014 01:54:06 64.676 -17.415 8.0 km 3.6 99.0 6.7 km NE of Bárðarbunga Tuesday
23.09.2014 01:51:51 64.656 -17.379 0.5 km 3.9 99.0 7.3 km ENE of Bárðarbunga Tuesday
23.09.2014 00:06:57 64.682 -17.422 7.9 km 3.0 99.0 6.9 km NE of Bárðarbunga

 

 

One very shallow at 01:51

Edited September 23, 2014 by NorthNorfolkWeather

[Freddie123]

Wonder if we are on the edge now of something significant happening or just an upturn for a few hours?

[NorthNorfolkWeather]

Wonder if we are on the edge now of something significant happening or just an upturn for a few hours?

I think it will keep us waiting,  we've had significant quakes (M4+) for over a month, could just keep going.

 

I think the main point is that it even has the experts guessing

[SteveB]

3.0 @ 8.4km

3.4 @ 7.9km

4.5 @ 6.2km

 

They are coming fairly regularly now.... 

[NorthNorfolkWeather]

3.0 @ 8.4km

3.4 @ 7.9km

4.5 @ 6.2km

 

They are coming fairly regularly now.... 

I noticed they were getting closer to the surface.  Not a huge amount of separation between the quakes in terms of distance either, I think as one fault pings the next up the line stresses and the itself goes

[BrickFielder]

GPS Shows a bit of a wobble in the downward movement around Bárðarbunga

 

Source of these images is the university of Iceland web site

 

http://jardvis.hi.is/gps_timaradir_vid_bardarbungu

 

 

GFUM Sil seems to have ice on the antenna again.

 

I would take this to indicate that the flow of magma into Bárðarbunga over the last 24 hours has matched or exceeded the eruption quantity. Which begs the question why subsidence at the caldera seems to be continuing. Although we should note that earthquakes have been somewhat deeper.

 

So here we go into the whacky world of theory again where I get everything wrong again. It turns out that inside a magma chamber not all magma may be in the same state. Some may be partially solidifed and some might be crystal mush and some might be very liquid magma. If there is a new injection of magma then some of the crystal mush may be reheated and become more liquid. When it does so I am guessing it will expand a little and put pressure on the magma chamber walls and roof.

 

Adding new magma to the chamber, in addition to transforming some crystalline material into liquid, a consequence of unlocking the crystal framework could be rapid convective overturn in the magma chamber, creating additional stresses on the surrounding rocky container.

 

https://depts.washington.edu/physpet/Publications_files/27-OB-GB-Elements.pdf

 

 

You would think this would tend to push up the caldera, but it may also push the walls of the chamber outwards. In a rifting environment are the walls more likely to move or 3-10km of caldera roof ? If it is the walls expanding then the ring faults would be moving outwards as well. Possibly causing the caldera to drop within the ring faults.

 

Ok some more links for those interesting in reading some more in depth thoughts.

 

ftp://seis.es.uwo.ca/pub/ktiampo/magma/Stress_magma_chamber.pdf

 

http://www.geotop.ca/pdf/stixJ/Kennedy_et_al_Nature_2008.pdf

 

 

As ever dont take anything I say too seriously as I might well be incorrect.

 

 

[john pike]

More Big Quakes in Bárðarbunga, Pollution in the East By Eygló Svala Arnarsdóttir September 23, 2014 07:40

Toxic gases are being emitted in the Holuhraun eruption. Photo: Jóhannes Benediktsson.

Three earthquakes above magnitude 3.0 have been measured around Bárðarbunga volcano under Vatnajökull glacier since midnight, the strongest of which, of magnitude 5.2, occurred at 4:30 am, approximately 7 km (4.6 miles) northeast of the volcano.

The volcanic eruption in Holuhraun north of Vatnajökull continues, as can be seen on webcams, ruv.is points out.

According to the Icelandic Met Office’s forecast, sulfur dioxide (SO2) pollution from the Holuhraun eruption site will likely be carried with westerly winds to the east across Hérað, Egilsstaðir and the East Fjords today.

In the evening, winds might start blowing in from the northwest, carrying gas to the southern East Fjords and Höfn.

Measurements of air quality can be found on the webpage loftgaedi.is. The Icelandic Met Office issues forecast on its webpage and warnings if conditions change for the worse.

Information on the SO2 pollution is now also available in English on the website of the Environment Agency of Iceland (see the tab to the right, Info and FAQ).

People who feel discomfort are advised to stay indoors, close their windows, turn up the heat and turn off air conditioning if there is visible haze. Use periods of good air quality to ventilate the house.

If you are outside, breathe through your nose as much as possible. Individuals with respiratory and/or heart diseases are strongly advised to have their medication with them.

 

 

http://icelandreview.com/news/2014/09/23/more-big-quakes-bardarbunga-pollution-east

 

 

 

[The PIT]

Brickfielder the magma that was already in there has been reheated and melted and then moved into the newly formed dike which allowed to drain away and only now is the input close to the output. It's quite possible there are small eruptions under the ice which we don't know about or magma is just forming sills and new dikes effectively being stored below ground. This could allow for an uptick in activity later if the input still exceeds the output and no further expansion of the dike or sills is possible.

[john pike]

http://www.livefromiceland.is/webcams/jokulsarlon/

 

look how much ice is in jokulsarlon now

 

[NorthNorfolkWeather]

A lot of steam rising tonight viewed from Camera 2

 

 

[john pike]

Eruption continues with steady and large lava output rate

Update Tue 23 Sep 08:51

The fissure eruption in Holuhraun continues with similar intensity as during the past days and shows no sign of stopping soon. The latest satellite images indicate that the lava now flows into two main branches, one (the older one) to the north and a new one to the east.

Astonishing lava volumes:

The lava flows erupted since the beginning cover around 37 square km and comprise a total volume of 0.4-0.6 cubic kilometers. If compared to an explosive eruption (for which the VEI scale was designed) using the Volcanic Explosivity Index (VEI) scale, the eruption has already reached the category VEI 5. It has so far erupted about the same volume of magma as the 1980 Mt. St. Helens eruption.

The discharge rate was estimated to 250-350 cubic meters per second. This corresponds to a cube measuring approx. 300 m on its sides. It would be enough to fill a soccer field with a pile 2-3 km tall of lava!

The subsidence of the Bardarbunga caldera continues with same rate as before, approx. 50 cm each day. It has now subsided by almost 30 meters in total.

Satellite image from 22 Sep, showing the 2 main lava flows from the Holuhraun eruption (image: Institute of Earth Sciences. Landsat 8, NASA & USGS)

Lava flow map as of 20 Sep (Institute of Earth Sciences)

 

http://www.volcanodiscovery.com/bardarbunga/seismic-crisis-2014/updates.html