Algerian Sahara - Usgs Earth As Art

This abstract in browns and grays from central Algeria shows that some parts of Africa's Sahara Desert contain much more than dunes of wind-blown sand. Barren ridges and fragmented mountains (lower right) border a vast expanse of arid plains etched with a complex system of dry streambeds. The streambeds contain water for brief periods following rare, intense rains that often cause flash floods. August 31, 2009.