Dune

Inphysical geography,aduneis ahillor ridge ofsand,usuallydepositedbyeolian processes(wind) or sometimes by the flow of water. Dune fields cover large parts of somedeserts,and somebeacheshave dunes.Marshas many dunes. Sand dunes have different forms and sizes based on their interaction with thewind.Sometimes they migrate downwind.

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v t e River morphology(or form)
Large-scale features	Alluvial plain Drainage basin Estuary Strahler number (stream order) River delta River sinuosity Drainage system (geomorphology) River valley
Alluvial rivers	Braided river Floodplain Meander Oxbow lake Rapids River mouth Anabranch Avulsion (river) Bar (river morphology) Channel pattern Cut bank Meander cutoff Mouth bar Point bar Riffle Riparian zone River bifurcation River channel migration Slip-off slope Stream pool Thalweg
Bedrock river	Canyon Knickpoint Plunge pool
Bedforms	Dune Ait Antidune Current ripple
Regional processes	Aggradation Base level Degradation (geology) Erosion and tectonics River rejuvenation
Mechanics	Deposition (geology) Water erosion Exner equation Hack's law Helicoidal flow Playfair's law Sediment transport List of rivers that have reversed direction
River system