Applied Geomorphology to assessment of natural hazards at the southern area of Pichilemu district, O’Higgins Region, Chile

Abstract

Based on an applied geomorphology approach, the coastal area between Punta Lobos headland and Cáhuil locality (O’Higgins Region) was studied with the aim of identifying and characterizing natural hazards, and also for evaluating the specific susceptibility of hydrometeorological hazards occurrence related to fluvial and ponding floods. Morphodynamic processes and conditioning factors that contribute to generate geomorphological instability were analyzed through geomorphological, historical, hydrological, and multitemporal analysis of aerial photographs and satellite images. In addition rainfall statistics procedures were utilized. From the obtained results, it was determined that the study area presents different hazard conditions (magnitude, frequency, spatial extent) due to landslides, liquefaction and soil erosion processes, but also fluvial, ponding, tsunamis and storm surge floods.