Rock fall
Also called: Rockfall · Topic: Geomorphic Processes: Weathering, Mass Movement, Erosion and Soil Formation · NCERT: Class 11, Ch 5 "Geomorphic Processes"
Meaning
A rock fall is the free falling of rock blocks from a steep slope or cliff. The falling blocks keep away from the slope face and do not slide along it. It is a kind of landslide, which here means a fairly dry, quick mass movement that you can clearly see. A rock fall takes away only the surface layers of the rock face. Frost, heating and cooling, and water in cracks loosen these outer blocks until gravity pulls them down. Rock falls are a common danger on hill roads.
Example
During the monsoon, rock falls often block the Rishikesh–Badrinath road in Uttarakhand. Loosened blocks drop from steep cut slopes straight onto the road.
Don't confuse with
- Rockslide: rock slides along a surface such as a bedding, joint or fault plane, and can involve rock to a great depth. A rock fall drops freely and affects only surface layers.
- Debris fall: the free fall of loose earth debris, not solid rock blocks.
Related concepts
- Mass movement
- Activating causes of mass movement
- Soil creep
- Solifluction
- Mudflow
- Debris avalanche
- Slump
- Rockslide