Causes, processes and risk assessment of a landslide on a talus slope of the Bavarian Alps

摘要

Landslides in the talus of limestone ― mountains sides are very rare. Such a disaster occurred in November 1996 in the catchment area of the Krottenthaler torrent in the Bavarian Alps. About 1,3 million cubic meters collapsed and slid or flowed into the valley bottom and partially closed it. The termination of the disaster and the landslide causes could be deduced by geological and geomorphologic surveys and investigations. In the year 1998 the situation could be estimated as stable with a small remaining risk. The masses at the toe of the landslide are now debris sources of the torrent. Floods, as they happened meanwhile, causes erosion at the flanks of the accumulations and increased sediment discharges. In consequence of the risk assessment and the hazard potential at the lower course a flood-dosing-dam with a retention basin was built to check debris flow depositions of agricultural and settlement areas efficiently.