ROCKMASS DEFORMATION AND ITS MECHANISM IN SANMASHAN RESETTLEMENT AREA OF FENGJIE COUNTY, THREE-GORGE RESERVOIR REGION

Because of the karst dissolution, the argillaceous limestone of the 3 rd member of middle Triassic Badong Formation (T 2 b 3 ), has been deformed in Sanmashan resettlement area of Fengjie County, Three-Gorge Reservoir region. On the basis of the deformation intensity, 3 different deformation zones are identified. They are slight dissolution-subsidence zone in the upper part(Ⅰ), dissolution-subsidence zone in the middle part(Ⅱ), and bank landslidein the lower part(Ⅲ). The dissolution subsidence zone(Ⅱ)is a main resettlement zone and should be kept off water. The bank landslide zone is difficult to control the slide and the resettlement buildings must be set away from there.