Eruption in the Bárðarbunga volcanic system in 2014

from Wikipedia, the free encyclopedia
Outbreak on September 4, 2014
Lava in Holuhraun, September 4, 2014

The eruption in the Bárðarbunga volcano system  [ ˈb̥aurðarˌb̥uŋg̥a ] 2014 began in the night of August 28th to 29th, 2014 and came to a standstill at the end of February 2015. He had been feared due to massive swarmquakes since August 16, 2014. On February 28, 2015, the Icelandic Meteorological Institute announced that the volcanic eruption had ended, but the outgassing continued. Please click to listen!Play

course

August 2014

Since August 16, 2014 there have been massive swarm quakes on and in the vicinity of Bárðarbunga. Within the first three days, 2800 single earthquakes - most of them with a magnitude of 1–2, the strongest on August 18 at 02:37 UTC (identical to the local time zone) with a magnitude of 4.5 - were registered. The quakes began under the caldera and moved north and east in two clusters in the following days.

On August 18, the warning level for the volcano was changed from “yellow” to “orange” - increased probability of eruption. The earthquakes were a strong indicator of magma movements below the surface. Their hypocenters were at a depth of 5–10 kilometers. For safety reasons, the areas and paths affected by a possible glacier run on the north side of Vatnajökull to Mývatn (road F910) and Öskjuleið LF88 south of Grímsstaðir have been closed. On the evening of August 19, a civil emergency was declared and the evacuation of these areas began.

By evaluating the data from GPS measuring stations around the volcano, a horizontal displacement of the earth of 14 cm was found between August 16 and 22. The average continental drift in Iceland so far has been about two centimeters per year. The frequency of the quakes continued to increase and on August 22, 2014 was over 1,000 individual quakes per day; the strongest occurred on August 21 at 23:50 UTC with a magnitude of 4.7.

On August 23 at around 2 p.m. UTC, based on the analysis of the seismic data, a small subglacial eruption under the Dyngjujökull northeast of the Bárðarbunga was suspected. The ice cover there was estimated to be between 150 and 400 meters thick. The warning level for the Bárðarbunga was raised to "red" and the airspace above the volcano was closed. The evacuated restricted area on the ground was expanded again and now also included the Dettifoss and the Jökulsárgljúfur National Park . Residents of Kelduhverfi , Öxarfjördur and Núpasveit were asked to follow the news and keep mobile phones ready to receive. On the afternoon of August 24th, the warning level was set to "orange" again and the airspace blockage was lifted, but the blockages on the ground remained in place.

The quake frequency had decreased somewhat since August 22nd, but the hypocenters had moved upwards and were now mostly at a depth of 3 to 5 kilometers. The strength had also increased: on August 24th at 0:09 UTC an earthquake with magnitude 5.3 and at 5:33 UTC one with magnitude 5.1 was registered.

In the meantime, the warning level for the Askja volcano , which lies northeast of Bárðarbunga, has also been raised to “yellow”.

On the night of August 28th to 29th, lava emerged in the Holuhraun lava field north of Dyngjujökull along a roughly 300 meter long crevice. The alert level in the region was then raised to "red". International air traffic was not affected.

On the morning of August 31, another crack opened at the same point north of Bárðarbunga over a length of 2 kilometers, from which lava and steam emerged. After the warning level had meanwhile been downgraded to "orange" again, it was now increased again to "red", which blocked the air space above the volcano. A lava flow formed in the course of the eruption.

Since September 2014

Lava fountains on the evening of September 13, 2014.

The convective pyrocumulus cloud that formed over the erupting volcano produced a weak multivortex tornado on the morning of September 3rd, and small tornadoes continued to form in the period that followed.

The seismic activity decreased somewhat, but there were concerns that the eruption might shift under the glacier . A rift valley formed, some of which lay under the glacier. More magma flowed into the dyke than erupted, causing the pressure to rise.

Above the Bárðarbunga caldera, the glacier sank, as of November 28, 2014 already more than 50 meters, with continued subsidence. The quake characteristics also changed; so the number of quakes decreased, but their strength increased. Furthermore, large amounts of sulfur dioxide (SO 2 ) were released. The ESA observed an increase in the SO 2 concentration over the North Sea from 1st to 4th of September. On September 18, the Icelandic Meteorological Institute measured a degassing rate of the volcano of 200 to 500 kg SO 2 and 250–750 kg CO 2 per second. On September 20, a total of 64 earthquakes were recorded in the volcanic complex, the two strongest reaching magnitudes of 5.0 and 5.1, respectively.

On September 23, a powerful north-west foehn transported sulfur dioxide emitted from the Bárðarbunga to Central Europe. In Austria , the highest sulfur dioxide values ​​since the start of the measurements were recorded in some places. The highest concentration was measured with 247 micrograms of sulfur dioxide per cubic meter of air on the Masenberg in eastern Styria , the legal limit value of the Air Pollution Control Act is 200 micrograms of sulfur dioxide per cubic meter of air.

On September 22nd, the Icelandic Meteorological Institute stated the ejection of lava at 250 to 350 m³ per second, the total output since the beginning of the eruption was estimated at 0.5 to 0.6 km³ of lava. By September 30th, the new lava field had increased to 48.2 km², and sulfur dioxide emissions were given as 35,000 tons per day. The earthquake activity also remained at a high level, since the start of activity on August 16, around 25,000 earthquakes have been registered in the volcanic complex. For comparison: in normal years without volcanic activity, around 10,000 to 12,000 earthquakes are registered across Iceland.

As of November 17, 2014, over 1 km³ of lava had been ejected and the lava field had reached a size of 72 km². By January 10, 2015, the area increased to 84 km². The thickness of the cooled lava in December was around 10 meters in the eastern sector of the field, 12 meters in the center and around 14 meters in the western sector around the lava lake above the crevice. The basalt field was criss-crossed by canals through which fresh lava flowed to the edges. The outlet temperature of the lava was around 800 ° C and only lost 1 ° C on its way through the canals. Analyzes of the lava also revealed that the magma that fed the eruption rose from a depth of 9 to 20 kilometers. In the period from August 16 to December 9, around 34,000 earthquakes were recorded in the region around the volcanic complex. The magnitude and location of the quakes could be determined at around 17,500, of which around 7,000 had occurred in the caldera of Bárðarbunga. In addition, GPS measurements showed that from the Dyke on a line of around 25 km in the direction of Urðdarhals and Kverkfjöll, the earth drifted apart by 1.3 meters.

The eruption, which continued until the end of February 2015, was the greatest in intensity in Iceland since the Laki eruption from 1783 to 1784. On February 28, 2015, the Scientific Advisory Board of the Icelandic Civil Protection Agency announced that the eruption in Holuhraun. Outgassing continued to occur. The warning level for the airspace was downgraded from "orange" to "yellow". It was precisely this fact that worried volcanologists . It was feared that the eruption openings would close, causing an increase in pressure in the volcano and, as a result, a huge eruption, which with an ash cloud could also disrupt the flight.

Webcams

There are the following webcams that observe the volcano from a distance:

  • at Grímsfjall , 30 km south of Bárðarbunga
  • at Vaðalda , east of the Askja -Caldera, about 60 km north of the Bárðarbunga
  • at Vaðalda, 2nd webcam

Web links

Individual evidence

  1. ↑ a b Bárðarbunga - updated information. Icelandic Meteorological Office, August 24, 2014, accessed on August 24, 2014 (English): "Observations show that a sub-glacial eruption did not occur yesterday"
  2. ↑ Bárðarbunga - update. Icelandic Meteorological Office, February 28, 2015, accessed March 1, 2015 .
  3. ↑ http://www.visir.is/2800-earthquakes-in-three-days/article/2014140818954
  4. ↑ http://ruv.is/frett/possible-volcanic-eruption-at-bardarbunga
  5. ↑ Archive link ( Memento of the original from August 24, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.  @1@ 2Template: Webachiv / IABot / www.vegagerdin.is
  6. ↑ Information from the Icelandic Civil Defense (almannavarnir.is) from August 19, 2014 in Icelandic: Lokanir á svæðum norðan Dyngjujökuls ( memento of the original from August 20, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. and in English: Civil Protection in Iceland ( Memento of the original from August 24, 2014 in the Internet Archive ) Info: The archive link was automatically inserted and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / www.almannavarnir.is @1@ 2Template: Webachiv / IABot / www.almannavarnir.is
  7. ↑ http://ruv.is/frett/landrek-upp-a-14-sentimetra-sidustu-daga
  8. ↑ http://earthquake.usgs.gov/earthquakes/eventpage/usb000s569#summary
  9. ↑ Bárðarbunga - updated information , accessed on 23 August 2014.
  10. ↑ http://www.ruv.is/frett/small-eruption-believed-to-have-started
  11. ↑ http://www.jonfr.com/volcano/
  12. ↑ http://en.vedur.is/earthquakes-and-volcanism/volcanic-eruptions/
  13. ↑ Archive link ( Memento of the original from August 24, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.  @1@ 2Template: Webachiv / IABot / www.almannavarnir.is
  14. ↑ http://en.vedur.is/earthquakes-and-volcanism/articles/nr/2947
  15. ↑ http://www.ruv.is/frett/fissure-eruption-in-holuhraun-lava-field
  16. ↑ http://www.ruv.is/frett/fresh-eruption-north-of-bardarbunga  ( page no longer available , search in web archives )  Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice.@1@ 2Template: Dead Link / www.ruv.is  
  17. ↑ http://www.skywarn.at/forum/viewtopic.php?f=45&t=19880&start=125#p312600
  18. ↑ http://www.blick.ch/news/ausland/schweizer-fotografiert-bardarbunga-spektakulaere-bilder-vom-tor-zur-hoelle-id3162184.html
  19. ↑ http://www.ruv.is/frett/scientists-advised-to-leave-holuhraun
  20. ↑ http://www.ruv.is/frett/subsidence-by-hundred-of-meters-possible  ( page no longer available , search in web archives )  Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice.@1@ 2Template: Dead Link / www.ruv.is  
  21. ↑ http://www.ruv.is/frett/gravely-concerned-about-bardarbunga
  22. ↑ Bárðarbunga , accessed September 28, 2014.
  23. ↑ http://www.zamg.ac.at/cms/de/umwelt/news/hohe-so2-in-teile-oesterreichs-durch-islaendischen-vulkan
  24. ↑ How sulfur came to Austria. In: science.orf.at. September 26, 2014, accessed November 24, 2017 .
  25. ↑ Bárðarbunga Update , accessed October 4, 2014.
  26. ↑ a b Holuhraun eruption - fresh video ( English ) In: ruv.is . November 17, 2014. Retrieved November 30, 2014.
  27. ↑ Satellite image of the week: 1,000 billion liters of lava. In: Spiegel Online . January 10, 2015, accessed June 10, 2018 .
  28. ↑ Bárðarbunga 2014, additional information (German)
  29. ↑ Growth of the Holuhraun Lava Field NASA Earth Observatory (English)
  30. ↑ Bárðarbunga 2014 - updated information (German)
  31. ↑ 100 Days of continuous eruptive activity of Holuhraun (English) (PDF document) Summary of the first 100 days of the activity
  32. ↑ Iceland. Civil Protection and Emergency Management: The volcanic eruption in Holuhraun has come to an end , February 28, 2015
  33. ↑ A silent volcano scares Iceland. In: news.orf.at. March 2, 2015, accessed November 24, 2017 .
  34. ↑ a b Another webcam put up overlooking Bárðarbunga volcano Article in Iceland Magazine from August 19, 2014, on: icelandmag.com
  35. ↑ Webcam at Grimsfjall on: vedur2.mogt.is
  36. ↑ Bárðarbunga webcam on the Vaðalda, at: livefromicierend.is
  37. ↑ Bárðarbunga-2 2. Webcam on the Vaðalda, on: livefromicierend.is