Abstract: Researches on the development rule of toppling deformation slopes is of great significance in prevention planning for toppling deformation and site selection for hydropower projects. And statistical research is conducive to the analysis of toppling deformation slopes in China. In this article, the west region of China is determined as the study area in view of the distribution of toppling deformation slopes. Four influencing factors are selected for geographical susceptibility zoning evaluation, namely landform, stratigraphic age, seismic intensity and tectonic stress distribution. Toppling deformation slopes of 11 rivers in west China are taken as examples for the evaluation of geographical position susceptibility. The relations between distribution features and development factors (lithology, slope height, slope angle, elevation, horizontal depth and vertical depth) are revealed according to the zoning results. Results show that 1) toppling deformation slopes mainly exist in Sichuan, Qinghai and Yunnan provinces; 2) Hengduan Mountains with extremely large and large heaves belong to the zone of extremely high susceptibility; 3) areas of high susceptibility are located in the middle reach of Yalong River, the middle and upper reaches of Lancang River, the upstream of Yellow River, Dadu River and Minjiang River. The research results offer reference for prevention planning of toppling deformation and site selection for hydropower projects in southwest China.

Key words: toppling deformation slope, regional geology, hydropower projects in west China, geographical position, susceptibility, development rule