mass wasting
The movement downslope of rock fragments and soil under the influence of gravity. The material concerned is not incorporated into water or ice, and moves of its own accord, but slides are often triggered by increase in water pressure on rocks and soil.
A widely used classification of mass movement uses the combination of types of movement (falls, topples, slumps, slides, and flows) with the nature of the material (bedrock, debris, and fine soil). In this classification, the term creep is synonymous with flow. Many cases of mass movement include more than one type of movement.
