Analysis of debris-flow events in the Eastern Pyrenees, Spain

摘要

A total of 89 debris-flow events was analysed by different types of approaches. Firstly, a statistical analysis of all the events was carried out in order to determine significant parameters related to the failure mechanism as well as to the mobility. Second, a numerical approach was applied to study the velocity and the runout distance of those debris flows that are characterised by volumes larger than 1000 m~3. The results indicate that most events initiated as shallow landslides in loose colluvium and transformed down-slope into debris flows. Moreover, there exists a relationship between the drainage basin area upstream of the debris flow initiation and the volume mobilised.