Bárðarbunga

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Bárðarbunga
Eruption in the 2014 Bárðarbunga volcanic system in Holuhraun on September 4, 2014

Eruption in the 2014 Bárðarbunga volcanic system in Holuhraun on September 4, 2014

height 2010  m
location Iceland
Coordinates 64 ° 38 '27 "  N , 17 ° 31' 40"  W Coordinates: 64 ° 38 '27 "  N , 17 ° 31' 40"  W.
Bárðarbunga (Iceland)
Bárðarbunga
Type Subglacial volcano
Last eruption 2014 (in the Holuhraun )
particularities covered by the glacier shield of Vatnajökull
Þjórsárhraun lava field

Þjórsárhraun lava field

The Bárðarbunga ( Bardarbunga ,  [ ˈb̥aurðarˌb̥uŋg̥a ] ) is a subglacial central volcano with a caldera under the Vatnajökull glacier in Iceland . It reaches a height of 2010 m, making it the second highest mountain in Iceland. With the connected system of fissures, it also forms the volcanic system of the same name . The last eruption of the volcano so far lasted from August 2014 to February 2015. Please click to listen!Play

location

The Bárðarbunga is located on the northwestern edge of Vatnajökull between Grímsvötn and Tungnafellsjökull . Some glacier tongues reach down to 1300 m in the direction of Vonarskarð . The most important one is Köldukvísljökull .

Surname

In his writings from 1794, the natural scientist Sveinn Pálsson speaks of Jökulfell when he means the Bárðarbunga.

The volcano was later named after the settler pioneer of the Viking Age Bárður Heyangur-Bjarnarson , who at the time of the conquest of the land first settled in Bárðardalur north of the Sprengisandur , which was also named after him , but then went south over the Bárðargata named after him (probably over the Vonarskarð pass ) Fljótshverfi had moved.

The Icelandic word bunga means arching in German .

Volcanism

The Bárðarbunga was little known for a long time because the volcano is so far away from the populated areas and also because of its position under the large glacier shield it produces relatively seldom visible eruptions.

However, geological studies have shown that under the ice, with an area of ​​80 km², one of the largest calderas in the country is hidden. It measures 10 km in diameter and is 700 m deep. It was first spotted on satellite images on January 31, 1973.

Bárðarbunga volcanic system

With the connected fissure systems, the Bárðarbunga also forms the volcanic system of the same name, approx. 150 km long. To the northeast it extends 50 km to the height of the Askja , in the southwest it extends 100 km to the border of the Torfajökull system.

The following units also belong to the volcanic system:

  • and many more rows of craters, crevice volcanoes and lava fields.

It has now been possible to assign numerous tephra layers , which were initially ascribed to other volcanoes, to the Bárðarbunga.

Eruption story

On average, the volcano erupted in the Holocene at intervals of around 250 to 600 years. Numerous prehistoric eruptions (i.e. before the 9th century) took place in the southwestern part of the volcanic system.

About 8500 years ago the most powerful effusive eruption of a series of eight events occurred in the area of ​​the Veiðivötn fissure system, with a volume of about 21 to 30 km³ of lava. The resulting lava field Þjórsárhraun covers an area of ​​950 km² with a total length of 130 kilometers, making it the largest lava field in Iceland.

Vatnaöldur and Veiðivötn

Two outbreaks after the settlement of Iceland are known: the Vatnaöldur eruption in 870 AD and the Veiðivötn eruption in 1480. Both outbreaks were relatively large; they produced rows of craters in the part of the Icelandic highlands that is northeast of the Hekla .

Torfajökull and Veiðivötn

In the 15th century, the huge explosive eruption on the Veiðivötn probably triggered another in the neighboring Torfajökull system. Something similar had happened in the year 870, and because dark basalt was expelled from the Vatnaöldur and light rhyolite in Torfajökull , one speaks here of the easily recognizable, because two-colored, land acquisition ash layer , which plays an important role in tephrochronology in Iceland . The settlement of Iceland is scheduled to begin around the same time.

Dyngjuháls

Smaller eruptions occur more frequently in the northeast of Bárðarbunga on the ice-free Dyngjuháls , the last of them from 1862 to 1864.

Subglacial eruptions

Studies of glacier ice and ash layers have shown that numerous eruptions also took place in and under the glacier itself, probably in the northeast of the caldera or in itself. These eruptions seem to follow a cycle, some between 1701 and 1740 and others after 1780. Another eruption was detected after 1864. The last clearly proven eruption took place in 1910 at Loki-Fögrufjöll (subglacial, explosive). Since then, several more undiscovered eruptions are suspected, but none of them have been detected so far, as they must have occurred under the ice sheet of the glacier.

Bárðarbunga and Gjálp

According to the latest findings, the eruption in Gjálp 1996 may have been triggered by a previous earthquake in Bárðarbunga. The eruption in Gjálp also triggered a small eruption in the neighboring volcano Bárðarbunga on November 6th, which only lasted briefly, but produced a 4000 m high eruption column .

Holuhraun

After the occurrence of massive swarm quakes since August 16, 2014, a persistent effusive fissure eruption began in the night of August 28 to 29 in the Holuhraun lava field northeast of the glacier and lasted until February 28, 2015.

Potential dangers

Proven cyclical series of earthquakes as well as smaller earthquakes occurring almost daily on the volcano point to the always existing possibility of further eruptions. The volcano is notorious for the courses of glaciers that flow into the lowlands in all directions when an eruption occurs. Lava flows and Tephrafall would also be dangers if a major eruption occurred.

At intervals of around 500 to 800 years there are always large crevices in the southwest of Bárðarbunga. This could affect and damage the numerous hydropower plants located there. The ash would also have a negative impact on air traffic and the climatic conditions in the North Pole region. The outbreak in August 2014 caused fears about health, environmental and climatic effects , primarily due to the increased discharge of sulfur dioxide .

Air crash in 1950

On September 14, 1950, the cargo plane Geysir of the airline Loftleiðir of the Douglas C-54 B type crashed on its return to Reykjavík from its first flight to Luxembourg at the Bárðarbunga at a height of 1,800 meters. Due to bad weather on the glacier and damaged radio equipment, the six-person crew was without contact with the outside world for several days. For the bailout an equipped with skis landed Douglas C-47 of the USAF on the glacier, but could not start again and had to be abandoned first. After six days, all crew members of both aircraft were rescued from Akureyri by a ski patrol, albeit partially injured . The C-47 was bought by Loftleiðir, salvaged in April 1951 and put back into service.

See also

literature

  • Hjörleifur Guttormsson, Oddur Sigurðson: Leyndardómur Vatnajökuls. Viðerni, fjöll and byggðir. Stórbrotin náttúra, eldgos og jökulhlaup. Fjöll og firnindi, Reykjavík 1997, ISBN 9979-60-325-9 .

Web links

Commons : Bárðarbunga  - collection of images, videos and audio files

Scientific treatises

Sport on the Bárðarbunga

Individual evidence

  1. ↑ a b Bárðarbunga in the Global Volcanism Program of the Smithsonian Institution (English)
  2. ↑ a b Íslandshandbókin. Náttúra, saga og sérkenni. 2. bindi. Örn og Örlygur, Reykjavík 1989, p. 937.
  3. ↑ a b Guttormsson, Sigurðson: Leyndardómur Vatnajökuls. 1997, p. 79.
  4. ^ Hans Ulrich Schmid: Dictionary Icelandic - German. With a brief Icelandic theory of forms. Buske, Hamburg 2001, ISBN 3-87548-240-9 , p. 33.
  5. ↑ Guttormsson, Sigurdson: Leyndardómur Vatnajökuls. 1997, p. 67.
  6. ↑ 2007 Field trip to Veiðivötn ESC - Annual Workshop in Volcano Seismology
  7. ↑ cf. G. Larsen, Thor Thordarson: Phreatomagmatism in the Eastern Volcanic Zone (English); Accessed July 25, 2010
  8. ↑ Hversu áreiðanlegar eru aldursgreiningar innan jarðfræðinnar? Háskóli Íslands, Dæmi 3. Vísindavefurinn, accessed July 25, 2010 (Icelandic).
  9. ↑ Bárdarbunga - Eruptive History. volcano.si.edu, accessed June 21, 2011 .
  10. ^ The Gjálp eruption in Vatnajökull 30/9 - 13/10 1996 , Institute of Earth Sciences, University of Iceland (English), accessed on August 10, 2010
  11. ↑ Page about volcanoes ( Memento of the original from August 22, 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. the Ríkisútvarpið RUV - The Icelandic National Broadcasting Service  @1@ 2Template: Webachiv / IABot / www.ruv.is
  12. ↑ a b Vatnajökull - earthquakes during the last 48 hours , Icelandic Met Office, retrieved on December 23, 2014, earthquake measurements by the Icelandic Meteorological Office: on Vatnajökull, the caldera of Bárðarbunga is located in the extreme northwest of the glacier shield, clearly marked as a ring opposite the alone standing Tungnafellsjökull. (English)
  13. ↑ Magnús T. Guðmundsson and others: Volcanic hazards in Iceland. Jökull , 58 , 2008, e.g. BS 254 ; Accessed September 14, 2014
  14. ↑ ELDGOS.IS Bardarbunga (Icelandic)
  15. ↑ Climate consequences of volcanic eruptions: It could get cold. In: Spiegel Online . October 10, 2014, accessed December 23, 2014 .
  16. ↑ Aircraft accident data and report of the accident involving the Douglas C-54B at Loftleiðir on September 14, 1950 in the Aviation Safety Network , accessed on August 25, 2014.
  17. ↑ Iceland's first airline: a nation takes to the air , article in Lögberg-Heimskringla of October 2, 1992 at Tímarit.is
  18. ^ Roger Boyes: Meltdown Iceland: Lessons on the World Financial Crisis from a Small Bankrupt Island . Bloomsbury, New York 2009, ISBN 978-1-60819-018-8 , pp. 34 ( online in Google Book Search).