A prehistoric catastrophic rock avalanche at Holsteinsborg, West Greenland.

Abstract

The deposits of a rock avalanche have been identified near Holsteinsborg, West Greenland, where they cover about 2km2 and involve at least 2.8x106 m3 of rock debris which has been transported up to 7km from its source. The possible transport mechanisms responsible for this deposit are discussed by analogy with recent rock avalanches. This suggests that the avalanche was a high velocity flow cum slide with a dispersed load of rock debris, snow and ice which was generated by a rock fall from the side of the mountain of Avqutikitsoq. The date of the avalanche is estimated from the somewhat uncertain lichenometrical evidence to be l6th or l7th century. -Author