Krafla
Encyclopedia
Krafla is a caldera
Caldera
A caldera is a cauldron-like volcanic feature usually formed by the collapse of land following a volcanic eruption, such as the one at Yellowstone National Park in the US. They are sometimes confused with volcanic craters...

 of about 10 km in diameter with a 90 km long fissure zone, in the north of Iceland
Iceland
Iceland , described as the Republic of Iceland, is a Nordic and European island country in the North Atlantic Ocean, on the Mid-Atlantic Ridge. Iceland also refers to the main island of the country, which contains almost all the population and almost all the land area. The country has a population...

 in the Mývatn
Mývatn
Mývatn is a shallow eutrophic lake situated in an area of active volcanism in the north of Iceland, not far from Krafla volcano. The lake and its surrounding wetlands have an exceptionally rich fauna of waterbirds, especially ducks...

 region. 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

Krafla includes one of the two best-known Víti craters of Iceland (the other is in Askja
Askja
Askja is a stratovolcano situated in a remote part of the central highlands of Iceland. The name Askja refers to a complex of nested calderas within the surrounding Dyngjufjöll mountains, which rise to , askja meaning box or caldera in Icelandic-Location:The region is only accessible for a few...

). The Icelandic word "víti" means "hell". In former times, people often believed hell to be under volcanoes. The crater Víti has a green lake inside of it.

The Krafla area also includes Námafjall, a geothermal area with boiling mudpools
Mud volcano
The term mud volcano or mud dome are used to refer to formations created by geo-excreted liquids and gases, although there are several different processes which may cause such activity. Hot water mixes with mud and surface deposits. Mud volcanoes are associated with subduction zones and about 700...

 and steaming fumaroles.

The Mývatn fires occurred between 1724–29, when many of the fissure vent
Fissure vent
A fissure vent, also known as a volcanic fissure or simply fissure, is a linear volcanic vent through which lava erupts, usually without any explosive activity. The vent is usually a few meters wide and may be many kilometers long. Fissure vents can cause large flood basalts and lava channels...

s opened up. The lava fountain
Lava fountain
A lava fountain is a volcanic phenomenon in which lava is forcefully but non-explosively ejected from a crater, vent, or fissure. Lava fountains may reach heights of up to . They may occur as a series of short pulses, or a continuous jet of lava. They are commonly seen in Hawaiian eruptions.-See...

s could be seen in the south of the island and a lava flow destroyed three farms near the village of Reykjahlíð
Reykjahlíð
The village of Reykjahlíð has approximately 300 inhabitants and is situated on the shores of Lake Mývatn in the north of Iceland. It is the seat of the municipality of Skútustaðahreppur.-Overview:...

, 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
Power station
A power station is an industrial facility for the generation of electric energy....

.
A survey undertaken in 2006 indicated very high temperatures at depths of between 3 and 5 kilometres and these favourable conditions have led to the development of the first well from the Iceland Deep Drilling Project (IDDP), that found magma only 2.1 km deep.

See also

  • Geography of Iceland
    Geography of Iceland
    Iceland is a medium-sized island in the North Atlantic ocean. The island is located east of Greenland and immediately south of the Arctic Circle, atop the divergent boundary of the Mid-Atlantic Ridge in the North Atlantic Ocean. It lies about from New York City and from Scotland...

  • Lakes of Iceland
  • List of volcanoes in Iceland
  • Volcanism in Iceland
  • Geothermal power in Iceland
    Geothermal power in Iceland
    Due to the special geological location of Iceland, the high concentration of volcanoes in the area is often an advantage in the generation of geothermal energy, the heating and production of electricity...


External links

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