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River landforms - OCRErosional landforms

Erosional landforms include V-shaped valleys, interlocking spurs, waterfalls and gorges. Meanders and oxbow lakes use erosional and depositional processes in their creation.

Part of GeographyDistinctive landscapes

Erosional landforms

The process of can create different landforms. The erosional features are often found in the of the river.

Waterfalls and gorges

A waterfall forms when water falls down hard rock in a steep sided gorge. A plunge pool forms. The overhang erodes and waterfall retreats.

A is a sudden drop along the river course. It forms when there are horizontal bands of resistant rock (hard rock) positioned over exposed, less resistant rock (soft rock).

  1. The soft rock is eroded quicker than the hard rock and this creates a step.
  2. As erosion continues, the hard rock is undercut forming an overhang.
  3. and erode to create a .
  4. Over time this gets bigger, increasing the size of the overhang until the hard rock is no longer supported and it collapses.
  5. This process continues and the waterfall retreats upstream.
  6. A steep-sided valley is left where the waterfall once was. This is called a .

V-shaped valleys and interlocking spurs

A spur is land jutting out causing a river to meander. Interlocking spurs cause rivers to keep meandering through a V-shaped valley.

In the upper course there is more . The river cuts down into the valley to form a narrow, steep-sided V-shaped valley. If there are areas of hard rock which are harder to erode, the river will bend around it. This creates of land which link together like the teeth of a zip.

A photo of a V-shaped valley
Image caption,
V-shaped valley in West Sussex