Determination of the Volume of Debris from Yingxiu Landslides, Southwest China: Geomorphological and Field Observation Approaches

Abstract

The May 12th 2008earthquake of magnitude 8.0 on the Richter scale,whichstruck the Yingxiu catchment, southwest China, triggered co-seismic landslides. Of these landslides, 41 were mapped and characterized during fieldwork, based on geomorphology and field observation. The landslide debris became a time bomb for the August 14th 2010 rain-induced debris flow that ravaged the Yingxiu community, leading to death toll of 56 people and destruction of properties worth millions of Chinese Yuan. This research was aimed at determining the volume of materials moved during the landslides. This may give an approximate value of the volume of the landslide debris still left in the catchment. This indicates the need for the assessment of the potential hazard of the catchment. The knowledge of the volume of materials moved can also be used in the calibration of landslides or debris flow model, especially in a data poor environment. Based on geomorphological mapping and field observation used, the volume of materials moved during the Yingxiu Landslides was 1,538,475.8 m3.