The Study About Susceptibility Of Geological Hazards On The Loess Plateau Area

As one of common nature disasters of the geological disaster, because of Geological disasters has the characteristics of wide distribution, strong activity, occurred at high frequency, threatens construction and normal operation of highway, affects production and living of people, even cause serious accident of casualties, the study of the geological hazard sensitivity evaluation can make it play an important role in disaster prevention and disaster reduction,and protect the lives and property of the people. Based on the analysis of the detailed investigation data in Linxia area of Gansu, combined with GIS technology, started system and in-depth study for the geological hazards sensitivity of Loess Plateau Linxia area by the analytic hierarchy process, the following results are obtained:1. Loess Plateau has the following characteristics:complex topography, gully everywhere, new tectonic activity strongly, and the vast areas covered by Loess Groundwater is mainly the loose rock pore phreatic water and fissure water. Distribution of lithology, geological structure is complex. The type of rock and soil is sandy loam, loam and clay (they are mainly composed of soil, loess and loess like soil special soil).2. In the study area, geological disaster types are mudslides, landslides and collapses and unstable slope. With the forming geological hazards, the main influencing factors are the topography, slope rock soil structure and geological structure, the secondary factors are groundwater and vegetation, the triggering factor are rainfall, earthquake and human engineering activities.3. In the study area, landslide plane is a convex shape and a straight line type, slope and height is main influencing factors of the formation of landslide. The variation is of landslide occurrence probability with the slope increases, the landslide formed in slope of 20 to 70 degrees, the avalanches formed in the slope is greater than 70 degrees. The solifluction occurres in the basin area is 0.1～5.0km, degrees of gully slope 15 to 45, longitudinal slope of principal sulcus drop 50～300‰.4. Based on the above research, using analytic hierarchy process to the research division of the district for geological disaster prone areas, prone areas, low and easy to send three zone. Furthermore, the high area is divided into 4 sub zones and in areas prone to divided into five sub zones and low easy hair is divided into three sub regions.