Disappearing KolbeinseyAs islet, defined as a very small island, can simply be a rock in the sea (Ba
Disappearing KolbeinseyAs islet, defined as a very small island, can simply be a rock in the sea (Ball’s pyramid off the coast of Australia: http://on.fb.me/10Xi6Bf), a sand bank (such as Oodaaq north of Greenland) or a river or tidal island (those in the river Thames). Kolbeinsey on the northern coast of Iceland is a basaltic islet which is currently only 42 m long and 5 m high. However, this was its size in 1989 and the islet has declined significantly ever since. No one has measured it in recent times. Reportedly, it was 700m long in 1616. Due to rapid erosion the island is expected to disappear by 2020. Actually, in 2006 half of the heliport of the islet, which was located on the highest point had disappeared. (Here you can see a picture of a much larger Kolbeinsey in 1932: http://bit.ly/ZvWsBX) Lately, it looks like Kolbeinsey actually compromises of two islets. There is no vegetation except for some mosses in summer. Basically, it is a barren en desolate place.The 14th century saga of the men of Svarfardalur mentions that Kolbeinsey was named after Kolbein Sigmundarson, an original settler of the Kolbeindalur (valley). He stranded on a rock northwest of Grimsey after he had become dissatisfied with the political circumstances in Iceland . Most likely he and his crew died on the island since there was no food or shelter. The islet was also known as Seagull Rock or Mevenklip. An 18th century poem of two brothers who sail to the islet is known in many variations, which mostly end in disaster. According to Icelandic folklore, the bones of the brothers still lay on the eerie islet and a devilish arctic fox is believed to inhabit it. In addition, sources mention seven other mysterious islands in the area of which Kolbeinsey supposedly was the biggest. Most likely the other islets disappeared into the sea a long time ago, if they ever existed at all.Kolbeinsey islet is part of the Kolbeinsey Ridge which compromises the northern portion of the Mid-Atlantic Ridge. The Mid-Atlantic Ridge, where tectonic plates are pulling away from each other creating new oceanic crust, walks straight through Iceland creating new land. The islet was formed in the late-Pleistocene or Holocene as a submarine volcano. A submarine eruption was reported in 1372. Other reports of activity have uncertain locations or have been discredited.The Kolbeinsey ridge is joined in the southeast by the Grimsey Oblique Rift, which has been very active lately. On the 2nd of April 2013 three major earthquakes occurred (M5.5, M4.7 and M4.5) which activated an intensive earthquake swarm that lasted weeks. There were a measured 712 earthquakes in two day’s time. The Grimsey Oblique Rift is characterized by strike-slip tectonics in which plates move up and down (similar to the San Andreas fault). For more information on earthquakes in Iceland see: www.vedur.is.–BOImage: Courtesy of Sindre Skrede. The image shows Kolbeinsey most recently in 2011.References and further reading:On this site you can see how Kolbeinsey has declined in size through time: http://bit.ly/XBKfik)http://en.vedur.is/about-imo/news/nr/2685http://www.volcano.si.edu/world/volcano.cfm?vnum=1705-01%3D -- source link
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