Research On Geological Disaster Risk Zone In Yang County Based On GIS

Yang County is located in the hinterland of the southern slope of the Qinling main ridge.In recent years, due to the poor conditions of the region and the adverse factors such asrainfall, earthquakes and human engineering activities, Geological disasters in Yang Countyshowed a clear upward trend. It is a serious threat to the lives and property of the people.Geological hazard zoning is through the range of possibilities and hazards of geologicaldisasters occur in the future to predict the risk area. It is not only used to reduce and avoid thehazards of geological disasters on people’s lives and property, guide the work of YangCounty relocation site, but also to provide scientific basis for Yang County economicdevelopment planning and environment protection.This paper relies on the Geological Survey of Yang County, Shaanxi Province. Throughthe reorganization of the investigation results of geological environment, geological hazardsconditions in Yang County, this paper has obtained the the types, characteristics and laws ofthe geological hazards in Yang County. Based on the sub topic The characteristics andlaws of the geological hazards in Yang County,This paper has selected terrain slope,landform, engineering geological rocks, geological structure, vegetation coverage, theaverage annual rainfall, human factors engineering activities the seven major indexes. Withthe GIS technical support, This paper has established Yang County geological hazardevaluation system, and ultimately selected the information quantity method to achievegeological hazard zoning. Meanwhile, This paper has established Yang County spatialdatabase and completed the extraction of the evaluation factors and rasterized layer. As aresult that the county rules by1km×1km grid is divided into3,429units. Combined theinformation quantity method with the Yang County spatial database, this paper obtains theinformation quantity of the seven major indexes in different conditions and finally gets thecomprehensive information values for each evaluation unit to achieve the geological hazardzonation by means of MAPGIS software, input editing, property database management, spatial analysis, engineering output function. As a consequent, the region is divided intohigh-risk zone, medium-risk zone, low-risk zone and very low risk zone and also draw thegeological hazard zoning map.