Characteristics and causes of the mudflow-landslides in loess

Landslides often occur in the heads and banks of some small valleys in loess area,and sliding distantly along the ditches,from a fewhundred to thousand meters. Sometimes,a large number of landslide deposits sliding out of the channel and forming a large fan-shaped deposit and bringing about unexpected loss. The shape of such landslides is similar to the viscous mudflow,but its causes not only by heavy rains but also by precipitation hysteresis,earthquake,freezing and thawing and irrigation. When the landslide slides along the channel,there are obvious and relative fixed sliding surface and sliding zone. Such landslides have more characteristics of landslide,and differences with mudflow. Thus,it is thought that it is a special kind of landslide and called mudflow-landslides in loess. The front part of the sliding body triggered by heavy rains may be transformed to mudflow,forming a landslide-mudflowdisaster chain. The causes and characteristics of such landslides are analyzed in this paper through the cases of the mudflow-landslides in loess in recent years.