LANDSLIDES HAZARDS ASSESSMENT WITH WEIGHTS OF CASE STUDY IN GUIZHOU, CHINA

Landslides are the most common geohazards in mountainous terrains and can cause extraordinary landscape changes and destruction of people's lives and properties. So assessing landslide hazards is significant and can provide valuable information to planners,developers and engineers. This paper examines some landslides at a hilly area of western China,Guizhou province. The purpose is to generate a landslide susceptibility map using the weights of evidence. It is based on the GIS technology and combined with landslides inventory and environmental factors. The causal factors include lithology,tectonic,elevation,slope,aspect,relief,distance from road and distance from stream. The weight of each causal class is calculated in a GIS software ArcGIS 10. Then the landslide hazard index of each unit is produced and divided into four classes: very high hazard,high hazard,medium hazard and low hazard. Finally,a success rate curve is built to detect the capability rate of the method. The study area under the curve is 0.71.A hazard zonation map is produced and the predictive power of the map is tested on the basis of landslides inventory. The evaluation results are in line with the landslides distribution. The weights of evidence are effective to assess the landslides hazard in regional scale.