sabkha

sabkha, saline flat or salt-crusted depression, commonly found along the coast of North Africa and the southern coast of the Persian Gulf. Sabkhas are generally bordered by sand dunes and have soft, poorly cemented but impermeable floors, due to periodic flooding and evaporation. Concentration of seawater and capillary discharge of groundwater result in deposits of gypsum, calcite, and aragonite. Most sabkhas are thought to have once been small sea inlets and are akin to basins in which evaporites formed in the geological past.