Theory question 304
Wind and Desert Landforms(a) Name three processes of wind transportation in an arid region. (b) With the aid of a diagram, describe the characteristics and mode of formation of a deflation hollow.
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(a) Suspension; saltation; surface creep (traction).
(b) Diagram: a shallow basin in the desert floor, sometimes reaching the water table with an oasis.
Characteristics: shallow or deep depression in a desert; may be very large (e.g. Qattara Depression); floor may reach the water table to form an oasis; gentle sides.
Formation: weathering loosens rock particles; strong winds blow away (deflate) the loose sand and dust; removal is repeated over a long time, lowering the land; deflation continues down to the water table, where moist ground stops further removal and water may collect as an oasis.
Name deflation as the process.