Where sand does not completely cover the desert floor and the prevailing wind consistently comes from one direction, what crescent-shaped dunes can form?

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Quizplus · Accepted Answer

Barchan dunes are crescent-shaped dunes that form in areas where sand does not completely cover the desert floor and the prevailing wind consistently comes from one direction. They have a gentle slope on the windward side and a steep slope on the leeward side, which gives them their characteristic crescent shape. Star dunes are not crescent-shaped, but rather have multiple arms that radiate out from a central point, and they can form in areas where winds come from multiple directions. Transverse dunes are long ridges that form perpendicular to the prevailing wind direction and are not crescent-shaped. Parabolic dunes are crescent-shaped, but they have arms that curve in the opposite direction of barchan dunes and form in areas where vegetation stabilizes the sand on the windward side, allowing the leeward side to migrate and form the crescent shape.

Where Sand Does Not Completely Cover the Desert Floor and the Prevailing