v. Landforms Made By Winds
Winds, particularly in hot deserts, cause deflation, abrasion, and impact. Deflation means the lifting and removal of dust and smaller particles from the surface of rocks.
The impact is a sheer force of momentum which occurs when sand is blown into or against a rock surface.
Abrasion is the physical process of rubbing, scouring or scraping whereby particles of rock (usually microscopic) are eroded away by friction.
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Erosional Landforms |
Depositional Landforms |
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Pediplains: When the high relief structures in deserts are reduced to low featureless plains by the activities of wind. Playas: Playa is a flat-bottom depression found in interior desert basins and adjacent to coasts in arid and semiarid regions, periodically covered by water Deflation Hollows: Deflation is the removal of loose particles from the ground by the action of wind. When deflation causes a shallow depression by persistent movements of wind, they are called as deflation hollows. Others – Mushroom, Table and Pedestal Rocks |
Sand dunes: According to the shape of a sand dune, there are varieties of sand dune forms like Barchans, Seifs, etc. The crescent-shaped dunes are called Barchans. They are the most common ones. Seif is similar to the Barchans but has only one wing or point. Longitudinal dunes form when the supply of sand is poor and wind direction is constant. Transverse dunes are aligned perpendicular to the wind direction. |