Landforms In Deserts
WIND EROSION
o Rock pedestals or mushroom rocks
o The sand-blasting effect of winds against any projecting rock masses wear back the softer layers so that an irregular edge is formed on the alternate bands of hard and soft rocks.
o Such rock pillars will be further eroded near their bases where the friction is greatest.
o This process of under-cutting produces rocks of mushroom shape called mushroom rocks or gour in the Sahara.
- Zeugen
- Yardangs
- Mesas and buttes
- Inselberg
- Ventifacts or dreikanter
- Deflation hollows
WIND DEPOSITION
- Dunes are hills of sand formed by the accumulation of sand and shaped by the movement of winds. They may be active or live dunes, constantly on the move, or inactive fixed dunes, rooted with vegetation.
- Barchan are crescentic or moon-shaped dunes that occur individually or in groups. They are live dunes that advance steadily before winds that come from a particular prevailing direction.
- Seifs or longitudinal dunes
- Loess
WATER ACTION
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Flash-floods
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Deep gullies and ravines
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Plavas, salinas or salars
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The Bajada is a depositional feature made up of alluvial material laid down by the intermittent streams.
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The Pediment is erosional plain formed at the base of the surrounding mountain scarps.