Basins

thumb|upright=1.5|View from the International Space Station of [[Lake Lucero in the Tularosa Basin, an example of a bolson.]] A bolson is a desert valley or depression, usually draining into a playa or salt pan, and entirely surrounded by recently uplifted hills or mountains. Bolsons are sites of active deposition of sediments (aggradation). They are a type of endorheic basin characteristic of basin and range topography.