Geography Option C - Desert landscape features

Yardangs

Ridges formed in areas of alternating hard rocks and soft rocks.

Abrasion by windblown sand erodes the softer rock faster

This leaves behind narrow, streamlined ridges aligned with the direction of prevailing wind

Deflation hollows

When wind removes fine, loose particles from desert surface through deflation

This leaves a shallow depression/hollows in the ground

Desert pavements

Wind removes fine material through deflation, leaving behind heavier particles

Coarse fragments accumulate and compact

Leaves behind a surface of large pebbles that protect the underlying sediments from further erosion

Wadi/Canyon

Formed after by a flash flood during a wetter pluvial period

Force of water erodes the sides and bottom of a river channel

Mesas/Buttes

Remnants of eroded plateau

Water from flash floods and rainfalls erodes the sides (softer rock)

Leaves steep-sided, flat-topped features protected by a resistant hard cap

Salt lakes/Playa lakes

Form when water collects in closed drainage basins after rare rainfall

Evaporates due to high temperature, leaving behind salts and minerals, creating a crusty, white lake bed

Sand dunes

Wind loses energy behind obstacles like rocks and vegetation and deposits sand

Sand accumulates, can grow and shift shape with changing wind direction

Dunes have gentle windward slope and a steeper leeward slope (slip face)