Answer
Landslide - According to Microsoft Dictionary, a landslide is the sliding down of a mass of earth or rock from a mountain or cliff.
Lahar - According to Microsoft Dictionary, a lahar is a destructive mudflow on the slopes of a volcano.
Creep - According to Britannica, a creep is a deformation and flow, in physics, alteration in shape or size of a body under the influence of mechanical forces. Flow is a change in deformation that continues as long as the force is applied.
Mudflow - According to Microsoft Dictionary, a mudflow is a fluid or hardened stream or avalanche of mud.
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