EXTRACTION AND ANALYSIS OF LUSHAN EARTHQUAKE TRIGGERED LANDSIDESA CASE STUDY IN BAOSHENG TOWN, YAAN CITY

On April 20, 2013, a strong earthquake of MS 7.0 struck the Lushan County, Sichuan Province, China. Because of the complex terrain conditions of the local area, the strong earthquake triggered numbers of secondary geological disasters, such as landslides, collapses, and debris flows. The Baosheng country, seriously attacked by slope mass movement disasters, was taken as an example for the study area in the paper. The combination of the remote sensing images and the DEM is used for visual interpretation. To evaluate and modify the accuracy of the visualization result, the spectral information and gradient information are then utilized. Moreover, the technology of spatial analysis and statistical analysis method is applied to the analysis of regularity of landslide mechanism, including topography, lithology, geological structure, and seismic intensity. The results show that the slopes of the earthquake-induced landslides are mainly concentrated in the range of 30～50,developed primarily in Mingshan group of earlier-Tertiary strata and Guankou group of Cretaceous composed of siltstone, mudstone and conglomerate, and mainly in the area of intensity Ⅸ.