Storegga slide
Coordinates: 64°52′N 1°18′E / 64.867°N 1.300°E
The three Storegga Slides are considered to be amongst the largest known landslides. They occurred under water, at the edge of Norway's continental shelf in the Norwegian Sea, approximately 6225–6170 BCE. The collapse involved an estimated 290 km (180 mi) length of coastal shelf, with a total volume of 3,500 km3 (840 cu mi) of debris, which caused a very large tsunami in the North Atlantic Ocean.
The three Storegga Slides are considered to be amongst the largest known landslides. They occurred under water, at the edge of Norway's continental shelf (Storegga is Norwegian for "the Great Edge"), in the Norwegian Sea, 100 km (62 mi) north-west of the Møre coast, causing a very large tsunami in the North Atlantic Ocean. This collapse involved an estimated 290 km (180 mi) length of coastal shelf, with a total volume of 3,500 km3 (840 cu mi) of debris. This would be the equivalent volume to an area the size of Iceland covered to a depth of 34 m (112 ft).
Based on carbon dating of plant material recovered from sediment deposited by the tsunami, the latest incident occurred around approximately 6225–6170 BCE. In Scotland, traces of the subsequent tsunami have been recorded, with deposited sediment being discovered in Montrose Basin, the Firth of Forth, up to 80 km (50 mi) inland and 4 m (13 ft) above current normal tide levels.
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