Comprehensive Evaluation On Geological Disaster Of Hongsibu,Wuzhong Town,Ningxia Province

By remote sensing interpretation and field investigation, the type, scale and environmental geological conditions of geological hazards in the Hongsipu District have been found out, analyzed in the investigation area and landslide, collapse, debris flow, ground collapse and unstable slope distribution and formation mechanism, and the development trend is predicted. Comprehensive evaluation model based on the Geographic Information System and quantitative and qualitative methods were used, and the regional geological hazard prone and dangerous was zoning evaluated, besides, a practical prevention plan of geological disaster was made. The main research results are as follows:First, fifty-five geological hazard points including one landslide point, one potential landslide point,eleven collapse points, thirty-six potential collapse points, four debris flow points and two surface collapse points were investigated in Hongsipu District by field survey. The development of geological disasters has many characteristics, such as large number, large scale difference, distribution concentration and so on.Second, the influencing factors of the landslide, collapse and debris flow mainly include the geological framework, the shape of the slope, the geological structure, the precipitation, the earthquake and the human engineering activity. The geological hazard of Hongsipu District is mainly distributed in piedmont diluvial oblique plain and the geological hazard points of alluvial plain, red-rock hills, loess hills and wind deposition sand area are very few. The geological hazards of diluvial oblique plain region are mainly collapses, potential collapses and debris flows. Collapses and potential collapses are mainly concentrated along rivers and large valleys, and debris flows mainly occur in the ravines of the piedmont inclined area forming high and medium prone areas. The ground collapse is mainly developed in the coal mining area.Third, by using the method of quantitative evaluation and qualitative analysis of GIS, the analysis of the geological hazards in Hongsipu District was carried out. among them, the high prone area covers an area of 267.55 square kilometer accounting for 9.71% of the whole area; the medium prone area covers an area of about 1296.97 square kilometer accounting for 47.06% of the whole area; the low prone area covers an area of about 1191.69 square kilometer accounting for 43.24% of the whole area.Fourth, according to the geological disaster prone degree, disaster risk degree and the scope of the threat, as well as regional environmental geological conditions and the construction of national economy and social development planning, of Hongsipu District and the geological hazard were quantitative assessment of risk zoning Among them, the high risk area covers an area of 342.88 square kilometer accounting for 12.44% of the whole area; the medium risk area covers an area of 1038.15 square kilometer accounting for 37.67% of the whole Hongsipu District; the low risk area covers an area of 1375.18 square kilometer accounting for 49.89% of the whole area.