Rockslides

the breaking off and falling of large masses of rock on steep and precipitous slopes of hills, mountains, stream and river valleys, and seashores. Rockslides occur as a result of weakening of the cohesion (integrity) of rocks, mainly under the influence of weathering processes, and the activity of surface and subsurface water. The volume of the largest rockfall, the Usoiskii rockfall, which took place on the Murghab River (Pamirs) in 1911, was about 2.2 billion cu m. A natural dam and Lake Sarezskoe were formed as a result of this rockslide.