Loess Landslide Types and Topographic Features at South Jingyang Plateau, China

The South Jingyang plateau, which has a total area of 70km², is located in Shaanxi Province, China. Groundwater table in this loess plateau has been significantly raised since 1976 when the loess cover began to be artificially irrigated. Up to now, more than 50 landslide events at 27 sites have occurred not only resulting in large economic loss and numerous deaths but also exacerbating water and soil erosion that reduced plateau area badly. After filed visits and landslide measurement at South Jingyang plateau, the following types of loess landslides there can be recognized on the basis of the initiative mechanisms: loess flowslide, loess slide and loess fall. We also analyzed the mechanisms of terrain-edge cracks and steep scarp and their relations with group-distribution and retrogressive occurrences of loess landslide. The mechanism of the long runout loess landslide has also been discussed.