STUDY ON WENCHUAN EARTHQUAKE-INDUCED LANDSLIDE RISK ZONATION

Landslides that are occurred during the earthquake are called seismic-landslides. This paper discusses the difference between the earthquake-induced landslide risk zonation and the general landslide risk zonation. It considers that some factors related to earthquake should be taken into the consideration in earthquake-induced landslide risk zonation. They include the distance between the landslide location and epicenter and the fault's buffer distance. They can reflect the role of earthquake dynamic energy to landslide formation. However, it is hard to reflect the earthquake effect in the vulnerability assessment. Five factors including landslide density, population density, road density, building density, and cultivated land density are adopted to evaluate the study area vulnerability. Finally, the contributing weight model is adopted to evaluate the landslide risk. The result shows that the higher and the high risk region are accounting for 9.03% and 14.61% of the whole study area respectively. This demonstrates that the disaster area after the Wenchuan Earthquake is still facing the landslide hazard threats. In the meizoseismal area, the counties of Beichuan, Qiangchuan, Dujiangyan, and Pengzhou should be regarded as the main landslide risk prevention areas. After field sampling and validation, the results are proved to be consistent with the actual Wenchuan earthquake regions. Thus, the method in this paper is reliable.