Research on Development Characteristics and Distribution of Landslides in Weibei Loess Tableland Area

On the basis of field investigation,remote sensing interpretation and engineering geological survey,the basic types,development characteristics and distribution of landslides in Weibei loess tableland edge are analyzed.Due to the geological structure,the river lateral erosion,lithology,human activities and other factors,the maximum density of landslides is up to 96.8%,and landslides distribution in the Loess Plateau edge of the northern bank of Weihe River,the west bank of Qianhe river,the east bank of Jinlinghe river and Changshou gully.Landslides have the following characteristics: imbalances,group-occurring,secondary and progressive in the same pace and so on.In addition,the Baoji-Weibei landlsides consist of three types: loess landslides,loess interface landslides and loess-hardclay cutting layer landslides.The last type of landslides is the most developed which accounts for 80% of the total number of landslides.Their sliding surfaces mainly locates among or between terrace clay,hipparion laterite and Pliocene hard clays.The scale of loess-hardclay cutting layer landslides is always huge and threats Baoji City.