RISK ASSESSMENT AND ZONING OF THE GEOLOGICAL HAZARDS IN MAYANG COUNTY OF HUNAN PROVINCE BASED ON WEIGHTED INFORMATION MODEL

According to the data of 1:50 000 detailed geological hazard survey in Mayang County, 9 factors including the density of geohazard sites, landform, structure type of rock-soil mass, geological structure, rainfall, vegetation, human engineering activity, threatened population and potential economic losses are selected as the evaluation indexes, and then the analytic hierarchy process (AHP) is used to rank and weight the importance of each index. Finally, the risk assessment and zoning of geohazards are carried out based on the weighted information model. The results show that Mayang County is mainly threatened by low-medium geohazards, among which the low and medium risk areas cover 984.44 km² and 414.08 km² respectively, with very low and high risk areas of 81.11 km² and 86.57 km² respectively.