Types and Characteristics of Typical Landslides Triggered by the M8.0 Wenchuan Earthquake

Abstract.

The M8.0 Wenchuan earthquake, which occurred on May 12, 2008 in Sichuan Province, China, induced thousands of geo-hazards. The most important and hazardous one was landslides, and caused serious casualties in worst-hit areas. The landslides show different characteristics compared with the gravity-driven landslides, because of the different responses of different geological and geomorphologic characteristics to earthquake-producing dynamic. On the basis of extensive field investigation, the induced landslides were classified into 3 kinds of basic types: slide-type landslides, slide-flow type landslides and fall-slide type landslides according to the movement characteristics and modes of the landslides. Moreover, according to the characteristics of the sliding and material composition of the slide-type landslides and macro disrupted degree of the sliding mass, sliding landslides were classified into three kinds of secondary types: coherent landslides, disrupted landslides and debris landslides. On the basis, basic characteristics, especially movement characteristics and processes for all types of landslides were thoroughly analyzed by different types of typical landslides cases. This is not only helpful to comprehensively understanding the types and characteristics of earthquake-induced landslides, but also can provide a mitigation and prevention basis for future earthquake-induced landslides.