Study Of Geological Hazard Risk In Yuanzhou On The Basis Of GIS

Based on the comprehensive analysis on the remote sensing interpretation data and fielddetailed survey data of geological disasters in YuanZhou, this paper had systematicallystudied development features and formation conditions of the various types of geologicaldisasters in Yuanzhou, developed the quantitative zoning evaluation of geological hazards inYuanzhou with a comprehensive evaluation model based on GIS, and made practical andfeasible anti-disaster plans. The main findings were as follows:1) there were283geologicaldisasters found out by the field survey, including81landslides,73collapses,123unstableslopes and6debris flows. Generally, the geological disasters, such as landslides, collapsesand unstable slopes, had the characteristics of large quantity, concentrated distribution,significant differences on scales and obvious predisposing factors. The surface morphology ofmost landslides was completed and the landslides mass were of large thickness. Thelandslides were mainly attractive landslides and will easily revive in the condition of heavyrains; the collapses were of small-scale but great harm; the unstable slopes were mainly withlinear or ladder slopes and of large-scale, and had big risks of potential sliding.2) Therelationship of geological disasters and the main factors was statistically analyzed, and thenthe evaluation index system of geological hazards was set up. The weight of each evaluationindex, including the intensity of disaster spots, the intensity of disaster area, slope gradient,slope height, slope type, geotechnical structure of the slope, rainfall, human engineeringactivities and seismic factor, was calculated with A.H.P.(3) Hydrology method based on theDEM in the computer automatically had been used to divide the slope units. The databasesystems and spatial analysis capabilities of the ARCGIS software platform were used toquantify and overlay calculate with comprehensive evaluation model. Then the geologicalhazard index of each evaluation unit is gained, and the result can be expressed as high-riskareas, mid-risk areas and low-risk areas.(4) A geological hazards prevention plan was givenout, and also a practical prevention plan had been made in order to prevent the happening of16geological hazards which had been picked out based on their high risks.The result of this paper has provided a scientific reference for land regulation, newcountry construction, and the prevention of geological disasters in social development,ecological and environmental protection in Yuanzhou. And the geological hazards of greatharm have been controlled by measures of monitor, avoidance, treatment, and so on. Thebenefits of this paper on environment and social are significant.