desert
Hot region where aridity (less than 4 in of annual rainfall) is such that plant and animal life is almost nonexistent.
saline lake 
Lake characterized by high salt content due to considerable water evaporation and the concentration of dissolved mineral salts.
oasis 
Desert zone made fertile by the presence of underground or surface water.
palm grove 
Zone where palm trees are planted.
wadi 
Often dry watercourse that is subject to sudden flooding in the event of rain.
mesa 
Isolated plateau with a flat summit and very steep sides; it features a layer of rock that is resistant to erosion.
rocky desert 
Most common type of desert, where rock fragments fracture due to temperature variations between night and day.
sandy desert 
Desert where minuscule grains of rock (sand) form dunes by wind action.
needle 
Tapering pointed column of rock shaped by the wind.
butte 
Rocky hill shaped by erosion, with steep sides and a flat summit; it is smaller in area than a mesa.