wind action

[geologia] s. ação do vento, f.; ação cólica, f.

Wind is the least effective of the agents of erosion and its effects are often exaggerated. It works best in areas where there is no surface vegetation, and where there are large exposed plains. These conditions are most readily found in a desert, near the margins of large ice sheets and sometimes in areas of farmland which have been cultivated. Sand storms rarely cause materials to rise more than two metres from the ground. Moving sand has an abrasive effect on rocks, smoothing off cliffs and any projecting exposed surfaces.Extensive loose deposits of sand are sorted by the wind and reworked into sand dunes.