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River landscapes – WJEC Erosional and depositional landforms

Large scale landforms are found in the upper course of a river, meanders and floodplains are found in the middle and lower course, and small scale landforms can be found along all stages of a river.

Part of GeographyLandscapes and physical processes

Erosional and depositional landforms

Meanders

As the river makes its way to the , it gains more water and therefore more energy, so material can be carried in suspension and is used to erode the river banks. starts to widen the river. When a river flows over flatter land it develops large bends called .

  • As a river goes around a bend, most of the water is pushed towards the outside. This causes increased speed due to less friction and therefore increased erosion (through and ).
  • The lateral erosion on the outside bend causes undercutting of the river bank to form a .
  • There is less water on the inside bend of a meander so friction causes the water to slow down, lose energy and deposit the material the river is carrying, creating a gentle slope.
  • The build-up of deposited sediment is known as a (small scale landform) or sometimes river beach.
The fast current on the outside bank causes lateral erosion, creating a river cliff. The slow current on the inside bank causes deposition, creating a slip-off slope.