Alluvial Fan:
A large, fan-shaped pile of sediment forming at the base of narrow canyons.
Alluvium:
Gravel, silt, and clay deposited by streams.
Arroyo:
A dry desert gully.
Dunes:
Mounds of loose grains of sand piled up by the wind.
Mesa:
Broad flat-topped hill.
Pediment:
A gently sloping surface usually covered in gravel.
Syncline:
An arced fold in the shape of an "u".
Desert Pavement:
A thin surface of closely packed pebbles.
Desert Varnish:
A hard, dark, shiny, coating on rocks.
Blowout:
A depression in the land surface created by wind.
