Mass wasting, or mass movement, is the process that moves Earth materials down a slope, under the influence of gravity. Mass wasting processes range from violent landslides to imperceptibly slow creep. Mass wasting decreases the steepness of slopes, leaving them more stable. While ice formation or water infiltration in sediments or rocks may aid mass wasting, the driving force is gravity. All mass wasting is a product of one or more of the following mass wasting processes: flow, fall, slide, or slump.

The four processes of mass wasting are distinguished based on the nature of the movement that they produce. Flow involves the rapid downslope movement of a chaotic mass of material. Varying amounts of water may be involved. Amud flow, for example, contains a large amount of water and involves the movement of very fine-grained Earth materials. Fall involves very rapid downslope movement of...