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1. With the aid of well labeled diagrams, describe the formation of:
i) A Barchan
(ii) Rock pedestal
(iii) An oasis
2. Name three features resulting from water deposition in desert

Answer Text:
i) A Barchan

- Sand accumulates around an obstacle lying on the path of wind.
- Deposition continues making the mound to grow bigger.
- Wind blows sand over leeward side creating smooth gentle windward slope.
- Wind eddies act on the leeward slope making it to be steep and concave in shape.
- Side wind move the sand grains on the sides forward creating the two edges which are curved.
ii) Wind abrasion acts upon rock with alternating hard and soft layers.
-Soft layers are eroded more than hard layers leaving hollows and protrusions.
- There is more undercutting at the base where there is more abrasion.
- There results an irregular rock with a narrow base

- Pre- existing depression/ localized fault attacked by wind eddies
- Depression is excavated by removal of unconsolidated materials/ wind erosion by
deflation
- When water bearing rock is reached/ aquifer water oozes out to collect in depression
and an oasis is formed
d) - Alluvial fan
- Bajada
- Salinas