Erosional Landforms
The process oferosionwhich creates different landforms along the coastline.
Headlands and Bays
Headlands are formed when the sea attacks a section of coast with alternating bands of hard and soft rock. The bands of soft rock, such as sand and clay, erode more quickly than those of more resistant rock, such as chalk. This leaves a section of land jutting out into the sea called a headland.
Abayis an inlet of the sea where the land curves inwards, usually with a beach.
Cliffs and Wave-Cut Platforms
Cliffs are shaped througherosionandweathering. Soft rock erodes quickly and forms gentle
sloping cliffs, whereas hard rock is more resistant and forms steep cliffs.
Awave-cut platformis a wide gently-sloping surface found at the foot of a cliff.
Formation of a Wave-Cut Platform
- The sea attacks the base of the cliff between the high and low water mark.
- Awave-cut notchis formed by erosional processes such as abrasion and hydraulic action - this is a dent in the cliff usually at the level of high tide.
- As the notch increases in size, the cliff becomes unstable and collapses, leading to the retreat of the cliff face.
- The backwash carries away the eroded material, leaving a wave-cut platform.
- The process repeats. The cliff continues to retreat.
Formation of Caves, Arches and Stacks
- Large crack opened up by hydraulic action.
- The crack grows into the cave by hydraulic action and abrasion.
- The cave becomes larger.
- The cave breaks through the headland, forming a natural arch.
- The arch is eroded and collapses.
- This leaves a tall rock stack.
- The stack is eroded forming a large stump.
Direction of cliff retreat is westward.
