Study On The Geological Hazard Classification For Susceptibility About Landslide And Collapse

Lintong district is located in the central area of Guanzhong Plain,the tectonic fracture development and the tourism boom,human activity intensity.Geological conditions of southern Rocky Mountains and hilly area of the Loess Plateau are complex,causing it is become to one of the geological disaster prone areas in Shaanxi province.The application of scientific methods to analyze and evaluate the Susceptibility of landslide hazard in the area,which can provide the basis for the disaster prevention and mitigation work.This thesis takes Lintong District of Shaanxi Province as the research object,Relied on the " detailed investigation of geological hazards in Lintong District of Shaanxi Province in 2016",On the basis of ascertaining the number and development characteristics of landslide hazard,the distribution regularities and the geological environment conditions about inducing its formation,Evaluating it on Susceptibility assessment and mapping the susceptibilities zone of geologic hazard about landslide and collapse in the study area.The main research contents are as follows:(1)Through the field reconnaissance,combining with the relevant data of regional geological hazard investigation,the development of landslide and collapse hazard in the study area can be obtained:There are 90 landslides and collapses in the whole area,of which there are about 40 landslides,accounting for about 44%of the total disaster.The Collapse disaster in 36,accounting for the total number of 56%.Through statistical analysis can draw,the main factors affecting the formation of collapse and landslide in the study area are as follows:Topographic and geomorphologic conditions,lithologic and tectonic conditions,Rainfall factor and human engineering activities.(2)Using statistical method combined with GIS spatial analysis platform,the spatial and temporal distribution of landslide hazard in the study area is summarized:Due to the south of the study area is mountainous and hilly landform,strong erosion,form broken,disasters,geological disasters in the northern environment,almost no development;landslides during the rainy season,the Holocene period and modern human activities strongly centralized occurrence.(3)Using the GIS mesh function Grid,The research area is divided into different scales grid.Calculating the total number of the disaster points under different scales,then carry through linear-regression analysis to lnN(r)-lnr and obtain the fractal dimension(Ds).The fractal dimension of the study area is 0.9357,which shows that the spatial distribution of the landslide and collapse disasters in this area has significant fractal characteristics.(4)Comprehensive analysis of landslides in this area the formation conditions and influencing factors,selected the topography,elevation,lithological assemblages,fracture development degree,the average annual rainfall and human engineering activities and disaster point density as evaluation factors,and using AHP,the index weights are given quantitatively,were:0.1471,0.0496,0.1741,0.1247 0.0626,0.2580,0.1839.(5)Based on the GIS platform,make the evaluation factor layer separately,and use the spatial analysis function of MAPGIS to overlay the area to get 468 evaluation units.Through the fuzzy comprehensive evaluation method,the relative membership degree of each evaluation unit is obtained,and finally,the division and evaluation of the landslides prone degree in the study area are realized.The results show that the whole area can be divided into 1 high-prone areas(A),and the 2 middle susceptibility zones(B1,B2),the 2 low susceptibility zones(C1,C2)and the 1 no-developed areas(D).