@Geoblogfeed: Geology between Pseudoscience and Pseudotachylite

Geoblogfeed

The landslide of Köfels: Geology between Pseudoscience and Pseudotachylite http://bit.ly/fckyBh


http://historyofgeology.blogspot.com/

The landslide of Köfels covers an area of at least 11,5 square kilometres with an estimated volume of 2 to 3 cubic kilometres, the largest landslide in the crystalline Alps. The landslide descended from the western slope of the valley, damming in transverse the Ötztal and branding against the opposite valley flank, this mass - the Tauferberg - blocked the mouth of the tributary valley of Hoarlach. The river of the Ötztal, the Ötztaler Ache, became dammed to a 7 kilometres long lake. In the basin of Längenfeld lake sediments have been drilled up to a thickness of 92m. Simultaneously the river has cut a deep gorge into the dam, the Maurach gorge is still today the only way trough the landslide barricade.
Pieces of wood recovered from a gallery driven in the Tauferberg during exploration work for a power station resulted in a conventional radiocarbon age of 8.710+/-150 years BP (ca. 9.800 years cal BP), this early Holocene age is supported by additional cosmogenic isotope dating of surface boulders that yielded an age of 8.889+/-490 to 10.630 +/-570 years BP.