Debris-Flow Runout and Deposition on the Fan

Abstract

Debris flows are at the interface of several research directions dealing with natural hazards processes. It is therefore not surprising that methods for the prediction of flow and runout of debris flows have similarities to approaches originally developed for snow or debris avalanches and streamflow hydraulics (Körner 1980; Lied and Bakkehoi 1980; Perla et al. 1980; Iverson 1997). However, debris-flow volume and bulk flow behaviour may change during travel through the channel, e.g. by entrainment of loose sediment and/or incorporation of water from a tributary. At present, no generally applicable model is able to cover the range of all possible material mixtures and event scenarios. This complexity results in different torrential processes and results in a large variety of approaches to predict debris-flow mobility.