Morphological characteristics of drainage networks related to landslide cluster in the Colombian Andean

Abstract

Debris flows are a highly destructive and common phenomena in Colombia. A large percentage are triggered during seasonal rainfalls. And the Andean region is the most affected area, which exhibits a dynamic landscape made up of weak and highly weathered materials and affected by tectonic stress. As a result of this setting, sometimes many landslides are generated in clusters. Those hillslope landslides are the sediment source for the formation of debris flows. The main goal of this study is to know the state of the dynamics of 3 basins that have been affected by cluster landslides and their subsequent debris flows that have occurred in the northern region of the Colombian Andes using diverse morphometric indices. In general terms, the results show a transitory state into basins, with an evident migration along the margins of the network drainages due to unbalance state. This means more susceptible areas with greater geomorphodynamic activity.