Krafla

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Krafla
Aerial View of Krafla and Leirhnjúkur 21.05.2008 16-08-27.JPG
Aerial view of Krafla (mountain) and Krafla caldera with Leirhnjúkur in 2008
Highest point
Elevation800 m (2,600 ft)
Coordinates65°44′0″N 16°47′0″W / 65.73333°N 16.78333°W / 65.73333; -16.78333Coordinates: 65°44′0″N 16°47′0″W / 65.73333°N 16.78333°W / 65.73333; -16.78333
Geography
Krafla is located in Iceland
Krafla
Krafla
Location in Iceland
LocationIceland
Geology
Mountain typeCaldera
Last eruptionSeptember 1984

Krafla (Icelandic pronunciation: ​[ˈkʰrapla]) is a volcanic caldera of about 10 km in diameter with a 90 km long fissure zone. It is located in the north of Iceland in the Mývatn region and is situated on the Iceland hotspot atop the Mid-Atlantic Ridge, which forms the divergent boundary between the North American Plate and the Eurasian Plate. Its highest peak reaches up to 818 m and it is 2 km in depth. There have been 29 reported eruptions in recorded history.

Overview[edit]

Iceland Mid-Atlantic Ridge map

Iceland is a place where it is possible to see plate tectonics at work. It sits astride the Mid-Atlantic Ridge; the western part of the island nation is part of the roughly westward-moving North American plate, while the eastern part of the island is part of the roughly eastward-moving Eurasian Plate. The north–south axis of the Mid-Atlantic Ridge splits Iceland in two, roughly north to south. Along this ridge many of Iceland's most active volcanoes are located; Krafla is one of these.[1]

Krafla includes the crater Víti, one of two well-known craters by this name in Iceland (the other is in Askja). The Icelandic word "víti" means "hell". In former times,[when?] people[who?] often[when?] believed hell to be under volcanoes.[citation needed] Víti has a green lake inside of it.

South of the Krafla area, but not actually within the caldera is Námafjall, a mountain, beneath which is Hverir, a geothermal area with boiling mudpools and steaming fumaroles.

History[edit]

The Mývatn fires occurred between 1724 and 1729, when many of the fissure vents opened up. The lava fountains could be seen in the south of the island, and a lava flow destroyed three farms near the village of Reykjahlíð, although nobody was harmed.

Between 1975 and 1984 there was a volcanic episode within the Krafla volcano. It involved nine volcanic eruptions and fifteen uplift and subsidence events. This interrupted some of the Krafla drillfields. During these events a large magma chamber emerged. This has been identified by analysing the seismic activity.

Since 1977 the Krafla area has been the source of the geothermal energy used by a 60 MWe power station. A survey undertaken in 2006 indicated very high temperatures at depths of between 3 and 5 kilometres, and these favourable conditions led to the development of the first well from the Iceland Deep Drilling Project that found magma 2.1 km deep beneath the surface.[2]

Photogallery[edit]

See also[edit]

References[edit]

  1. ^ Kious, W. Jacquelyne; Tilling, Robert I. (February 1996). "This Dynamic Earth: The Story of Plate Techtonics. Chapter 3: Understanding plate motions - Divergent boundaries". United States Geological Survey. USGS. Retrieved 15 January 2020. The volcanic country of Iceland, which straddles the Mid-Atlantic Ridge, offers scientists a natural laboratory for studying on land the processes also occurring along the submerged parts of a spreading ridge. Iceland is splitting along the spreading center between the North American and Eurasian Plates, as North America moves westward relative to Eurasia.
  2. ^ http://www.iddp.is/ Iceland Deep Drilling Project

External links[edit]