Theory question 304
Oceans and Lakes(a) What is a lake? (b) Describe the formation of lakes by wind erosion. (c) Identify three benefits of lakes to man.
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(a) A lake is a large body of water lying in a hollow (depression) on the land surface, surrounded by land.
(b) In deserts, strong winds remove loose dry sand and dust (deflation); eddies deepen and widen the depression; deflation continues down to the water table, where moist ground stops further removal; groundwater seeps in, or rain water collects, forming a lake or oasis, e.g. Qattara Depression, lakes in the Kalahari and Sahara.
(c) Water for domestic use and irrigation; fishing; transport; HEP (man-made lakes); tourism and recreation; moderation of local climate; source of minerals (salt, trona); habitat for wildlife.
Explain each step of deflation.