The Building Of The Geological Hazards Database And Hazard Assessment In Pingchang County Based On GIS

Pingchang County is located in southeast of Bazhong city and the south of Micang mountain,where with complex landforms,which is mainly composed with low mountains,some combining hills and middle mountains.Frequent geological disasters seriously affect the lives and property of the people and the local economic development there.Pingchang County lacks a scientific and effective geological disasters query,management,analysis platform and the overall evaluation of geologic disaster hazard assessment due to technical limitations.Therefore the building of the geological hazards query and management system will provide a scientific and efficient platform to geological disasters query,management and the hazard assessment in Pingchang County will also make a great contribution to the understanding of geological disasters development distribution,current distribution status and development trend of scientific forecast.According to the classification and unified coding of the geological disasters,combining with the landslides,collapses and debris flows,this paper has built the outside attribute data based on Microsoft Access.At the same time,the geological disasters spatial database also has been built based on the platform of Arc GIS.The outside attribute data and the spatial database is linked through unique fields,completing the building of the geological hazards personal geodatabase in Pingchang County at last.On the basis of geological hazards database,which has been established,and combining with the second development by C# and Arc Engine realized,the geological disasters query and management system of Pingchang County is built,Achieving functions of geological disasters spatial database query,management and spatial analysis,etc.Based on field survey and interior data analysis,and summarizing the geological disasters distribution characteristics and influence factor,the six factors of formation lithology,elevation,altitude difference,slope gradient,slope aspect and profile curvature were selected as the geological disasters hazard assessment factors.With the spatial analysis,statistic analysis,Average processing and normalization processing,the intra-weight and inter-weight of each assessment factor were obtained from the contributing weight model.After that,hazard zoning model was established according to principle of factors superposition.A distribution map of geological disasters in Pingchang County was achieved finally,by using natural breakpoint method,this distribution map of geological disasters was divided into three grades: lowly hazardous zone,moderate hazardous zone,highly hazardous zone.Pingchang County geological disasters prevention and control measures are put forward on this basis at last.