A slope collapse with a backward rotation is a "slump".
A slump is a form of mass wasting that involves movement along a curved surface, the upper part moving downward while the lower part moves outward.
Mass wasting is the gravity driven down-slope movement of earth materials. There are numerous types of mass wasting distinguished by the type of earth material moving down-slope, the speed with which it moves, and sometimes the mechanics involved in its motion.
The following are all types of mass wasting: creep, earthflows, landslides, mud and debris flows, rockfalls, rock and debris avalanches, rockslides, rock topple, and slumps.
Geologic, climatic, and human factors may all contribute to the occurrence of mass wasting events.
To learn more, visit the National Park Service.
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