Rivers GCSE AQA - Erosion, transportation and deposition

Water flows over cracks in the banks and bed, causing pressure in them to rise. As the pressure rises, the cracks expand until pieces of rock break away.

• Abrasion

• Attrition

• Hydraulic action

• Solution

Sediment transported in the river collides with the banks and bed. This means that pieces of rock are chipped away from the banks and bed.

• Abrasion

• Attrition

• Hydraulic action

• Solution

Rocks transported in the river collide with each other. This means that they become smaller, smoother and rounder.

• Abrasion

• Attrition

• Hydraulic action

• Solution

Weak acids in the river water dissolve the bed and banks.

• Abrasion

• Attrition

• Hydraulic action

• Solution

Large, heavy pieces of sediment are rolled along the bed, dragged by the river flow.

• Traction

• Saltation

• Suspension

• Solution

Pebbles are temporarily suspended by the river flow before being deposited. This means that they bounce along the bed.

• Traction

• Saltation

• Solution

• Suspension

Small pieces of light sediment, such as clay, are carried by the river flow. This means that they do not touch the bed.

• Suspension

• Traction

• Saltation

• Solution

Pieces of sediment that are dissolved in the water are moved as the river flows.

• Saltation

• Suspension

• Solution

• Traction

Rivers deposit sediment when their energy is _____.

• Low

• High

Rivers have high energy when their velocity is _____.

• Low

• High