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Coastal landscapes – WJEC Erosional landforms

Large scale landforms include headlands/bays, beaches, cliffs, arches, stacks, spits and wave-cut platforms. There are also small scale landforms such as rock pools and wave-cut notches.

Part of GeographyLandscapes and physical processes

Erosional landforms

The process of can create different large scale landforms along the coastline.

Headlands and bays

along the coastline do not erode at the same pace. A cliff is a steep rock face. When a stretch of coastline is formed from different types of rock, headlands and bays can form.

Bands of soft rock such as clay and sand are weaker, therefore can be eroded quickly. This process forms . A bay is an inlet of the sea where the land curves inwards, usually with a beach. Hard rock such as chalk is more resistant to the processes of erosion. When the softer rock is eroded inwards, the hard rock sticks out into the sea, forming a . An example of this is Saundersfoot Bay in Pembrokeshire, and Worms Head in Gower, Swansea.

Erosional features such as and cliffs can be found on headlands, since they are more open to the waves. Bays are more sheltered with which deposit sediment to form a beach. An example of wave-cut platforms can be found on the Glamorgan Heritage Coast at Porthkerry.

Waves attack the soft rock between sections of hard rock. This is differential erosion. The coastline changes over time, forming a bay where the erosion takes place, and a headland on either side.

Cliffs and wave-cut platforms

Cliffs are shaped through erosion and . Soft rock erodes quickly and forms gentle sloping cliffs, whereas hard rock is more resistant and forms steep cliffs. A wave-cut platform is a wide gently-sloping rocky surface found at the foot of a cliff.

Sea attacks base. Wave-cut notch forms. Cliff collapses. Wave-cut platform forms. Cliff retreats.

A wave-cut platform is formed when the following occurs:

  1. The sea attacks the base of the cliff between the high and low water mark.
  2. A (small scale landform) is formed by erosional processes such as and , this is a dent in the cliff usually at the level of high tide.
  3. As the notch increases in size, the cliff becomes unstable and collapses, leading to the retreat of the cliff face.
  4. The backwash carries away the eroded material, leaving a wave-cut platform.
  5. The process repeats. The cliff continues to retreat.
  6. Rock pools (a small scale landform) are left which often home a wide range of marine life as well as attracting many tourists.