ABSTRACT
Geomorphological studies of alpine slopes have emphasised the role of extreme events – rockfalls, landslides, mudflows and debris slides, flows, avalanches. strophic events may dominate morphological development of alpine slopes; indeed, in arid mountains even constructional landforms such as debris fans are caused by rare, extreme debris flows. Soil investigations have been used to approach these issues in a study of catastrophic slope erosion in Ulvadalen, western Norway. The tree line history of the Romsdal area is unknown, but there is evidence for Flandrian fluctuations elsewhere in Scandinavia. The main pedological influence on slope stability is thought to lie in the temporally-increasing drainage impediment which arises because translocation rates into the B horizon are maintained while the increase of solum thickness becomes slower. Various dated surfaces have been used to establish soil ‘chronosequences’, including fluvial deposits, till, mining debris, volcanic material, aeolian sand, raised shoreline sediments and slope deposits.
