关键词: 多元统计, 探索性因子分析, 灾害分布, 地震次生灾害： 多因素分析

Abstract:

The multivariate statistical analysis is applied to study the secondary geological disasters in four river basins of Suishui River, Chaping River, Mianyuan River and Shitingjiang River in Longmenshan area where the geological disasters were the densest in 5.12 Wenchuan Earthquake. Through Exploratory Factor Analysis, the ten factors that influence the development of earthquake secondary disaster have been reduced to five factors as the fault distance, elevation and geologic structure factor, the distance factor, the direction factor, the gradient factor and the relative elevation factor. The weight analysis of these factors explains the important distribution characters of the earthquake secondary hazard in Longmenshan area, that the hazards are in a zonal distribution along the seismic fracture and has a significant hanging/foot wall effect. Meanwhile, the statistical analysis results indicate that the development of the hazard is more easily to be affected by macroscopic factors such as fault distance and absolute elevation in strong earthquake areas, so in the susceptibility analysis of secondary geological hazard in the area near active fault and the potential earthquake source area, even the slope with favorable tectonics and geological structure should be brought into in the evaluation range by comprehensively considering the influence of the fault distance and absolute elevation.

Key words: multivariate statistics, Exploratory Factor Analysis, hazard distribution, earthquake secondary disaster, multi-factor analysis