Rainwash, also spelled rain-wash or rain wash or sometimes called hillwash, is a process of
erosion
Erosion is the action of surface processes (such as water flow or wind) that removes soil, rock, or dissolved material from one location on the Earth's crust, and then transports it to another location where it is deposited. Erosion is distin ...
in which loose surface material is carried away by rainwater that has reached the surface but has not yet become concentrated into rivulets. The term is also applied to the movement under the force of gravity of material loosened by rainwater, or to the material itself.
Rainwash is sometimes regarded as a combination of two processes: ''rain-splash'', which is the detachment and movement of small soil particles from raindrop impact, and ''soil-wash'', in which material is moved downslope by surface water flow.
References
Erosion
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