Hazard Maps of Shallow Landslides Associated to Infiltration Processes in the Sapuyes River Basin

Abstract

Hazard mapping of shallow landslides associated with infiltration processes at a regional scale was carried out by means of the spatial and temporal distribution of safety factor and its classification, within hazard level ranges, into cells that represent hillside units in Sapuyes river basin, located near the city of Pasto in the Nariño department. Hazard assessment follows the theoretical approaches of the Iverson model (2000), which takes into account the redistribution of underground pore pressures associated with the transient infiltration of the rain and its effects on the time and location of landslides, considering that shallow landslides are associated with periods of rain with a short duration and greater intensity. Results showed that both the pressure heads and the safety factor are valid approximations for hazard analysis at regional scale and allow observing the transient physical process involved in the development of shallow landslides.