GIS-Based Geological Hazard Mapping Using Statistical Analysis and Cell Assignment Method for Western Sichuan Region, China

Abstract

Geological hazards pose severe threats to the natural ecological environment, which endanger human life, cause damage to the environment, and undermine social stability. Studying geological hazards is intended to minimize or reduce any potential losses or threats. Although geotechnical hazards present a complex problem, hazard mapping and zoning studies can improve predictions and reduce losses. Based on the principle of geological hazard zoning, this paper describes a GIS-based approach to regional mapping for geological hazards, including collapse, landslide, debris flow, and overall geological hazards. First, four main factors affecting the occurrence of geological hazards, namely, digital elevation model (DEM), soil property, vegetation type, and average annual rainfall, are determined for analysis. Afterward, the investigated region of western Sichuan province, China, is divided into cells using GIS. The factors are then valued and assigned to the cells for statistical analysis. According to the relationship between the development/occurrence of geological hazards and various influencing factors, the region is first zoned with different degrees of susceptibility. Moreover, the response degree values for different levels of susceptibility to different influencing factors are determined for each cell, and then the superposition values of response degree for each cell are calculated for different geological hazards. Finally, the mapping of each geological hazard is done based on the calculated superposition value ranges. The mapping result demonstrates that the proposed approach is efficient and practical for determining the hazard susceptibility of regional geological hazards in western Sichuan province. The conclusions of this study can provide valuable information regarding the prevention and management of similar disasters in a region.