出典:Wikipedia
出典:『Wikipedia』 (2011/07/08 17:46 UTC 版)
Corrasion is a geographical term for the process of mechanical erosion of a rock surface caused when materials are transported across it by running water, glaciers, wind, waves or gravitational movement downslope, for example, the wearing away of fine particles of rock on a river or seabed by a sandpapering action, causing it to collapse and form a dip in the bed. The resultant effect on the rock is called abrasion. This sometimes happens at the bottom of cliffs to a slanted edge. Other forms of sea erosion include hydraulic action and attrition.