关键词: 中高山地区, 滑坡形成, 主控因子, 主成分析

Abstract: The form of a landslide is a combination of internal static intrinsic factors and the external dynamic triggering factors. For the internal intrinsic factors, the impact of the topographic, tectonic and lithological conditions on the landslide development is different.  A thorough analysis the relationships among these factors are important to the reveal of the mechanism, forecast as well as mitigation of the landslides. This paper presents the investigation results of 51 landslides in Tongren Prefecture, Guizhou Province. The eight (8) factors: the topography of the slope, slope angle, elevation difference, lithology underneath the potential sliding body, bedrock inclination, geological structure of the sliding area, thickness of the sliding body as well as the inclination angle, are analyzed by using the principal factor method. The influence of each factor is able to be quantified; therefore, the weighted influence factor is assigned to each factor. A landslide evaluation model in Tongren Prefecture is established on the principal influence factors. The results indicate that the following six (6) factors:  the topography of the slope, the inclination angle, slope angle, elevation difference, lithology underneath the potential sliding body, and bedrock inclination, are the principal influence factors in the landslide in the Tongren Area. Among these principal factors, the sliding body factors (lithology underneath the potential sliding body, the inclination angle and the geological structure of the sliding area) are the first and primary controlling factors. Whereas, the slope surface factors (the topography of the slope, slope angle and the elevation difference) are the secondary factors.  The sliding surface factor (inclination angle of the sliding body) is the third controlling factor.

Key words: Mountain Areas, Development of Landslides, Principal Factors, Principal Factor Method