ABSTRACT
Landslides occurred frequently in China and they are characterized by their large scale, complex mechanism of formation and serious destruction. Large-scale landslide has a large incidence due to its instability, great potential, and always breaks away from mother rock, and then forms high-speed, long distance collapse-slide-fluid complex hazard geological bodies, causing destructive breakage and heavy death. In the world, China is one of the areas where the most severe landslide hazards happen. Since 1980s there has been a trend to aggravate the landslides due to high-speed development of engineering constructions and change of corresponding natural characteristics. The landform of Danba, which was marked by strong uplift due to neotectonic movement and sharp downcutting of the Dajin River, provided favorable conditions for development of the landslide. The river-blocking event of the extraordinary Yigong Landslide included collapse-landslide clasticgrain flow blocking river-the lake breaking-flood-remodeling terrain of the river valleysecondary collapse and slide of the valley, which was a very complete geological hazard chain.
