Abrasion (geology)

Corrasion ( lat. corradere to " scratch ", " grind " ) primarily denotes the removal of rock by wind touches, but also comparable processes in rivers as well as in machinery and technical equipment.

Corrasion by wind

Corrasion or Windabrasion refers to the removal of rock by moving material (dust, grains of sand, fine gravel ) with the character of a sandblasting machine. The surface of the rocks then receives a cut ( Wind Cut ). Expression and strength of corrasion depend on the wind speed, the wind direction and the resistance and of the land cover ( absence of vegetation), the precipitation and the opportunities for the wind to attack here and take particles ( deflation). A low ground cover in combination with a high proportion of sediments or unconsolidated rocks of low to medium grain size ( coarse silt, sand, fine gravel) favor the corrasion.

The effects caused by corrasion rock formations have, depending on the above conditions on different forms, which is why mushroom rocks, Yardangs, ventifacts, grooves and wind bites differs.

Furthermore, there is the appearance of the scree caused by caused by wind abrasion from previously covered with sharp-edged rock fragments surfaces.

Corrasion by water

In rivers, the term refers to the crushing of entrained debris and the concomitant erosion of the walls in cave systems.

Corrasion in the art

In the technical field is meant by corrasion the mechanical destruction or attrition of machine parts by solids. This problem is a problem of its final solution is still far away even with modern, the pressure lines upstream tailings ponds, especially in the Pelton and Francis turbines of high-pressure pump storage power plants.