Rainfall as a trigger of shallow mass movements. A case study in the Dolomites, Italy

Abstract

 The article presents results of regional analysis on a historical basis correlating the occurrence of shallow mass movements and disruptive events in time with precipitation trends. For the latter, different time-spans have been considered in an attempt to find the most typical ones which might have triggered landslides. Research was carried out in the 850 km² wide basin of the River Cordevole in the Dolomites (NE Italy). Data concerning slope movements and floods, which have affected the area since the last century, were collected. Events which took place after 1920 have been correlated with the significant pluviometric events recorded. In spite of the regionally high variability of both geological conditions and spatial distribution of precipitation, three types of typical pluviometric trends related to an effective rainfall period of 15 days and to a peak rainfall of 24–48 h preceding the onset of the movements were identified.