The three main processes of a river are erosion, transportation and deposition. Explain what causes these main processes to occur.

Erosional processes:

• Hydraulic action: Force of water on river bank undercuts and removes material.
• Corrasion: Rocks bounce against side and bottom of river and break off more material. Attriction:
• Rocks collide with each other and break up into smaller pieces.

Transportation processes:

• Solution: Dissolved material being carried along by the river.
• Suspension: Small particles carried along by the river.
• Traction: Particles carried along the river bed.
• Saltation: Bedload particles bounced along the river bed.

Deposition processes:

• Deposition: River slows and dumps material including silt.