Cliffed coast

In coastal areas in which the land surface dips at a relatively steep angle below the water table, the continuous action of marine waves on the coastline, known as abrasion, may create a steep declivity known as a cliff, the slope angle of which depends on a variety of factors including the jointing, bedding and hardness of the materials making up the cliff as well as the erosional processes themselves.

The waves attacking the cliff-foot form a wave-cut notch by constant abrasion action producing an overhang.

The speed at which this happens depends, in particular, on the strength of the surf, the height of the cliff, the frequency of storm surges and the hardness of the bedrock.

On a cliffed coast made up of material which is only fairly or even hardly resistant to erosion no wave-cut platform but a beach is formed in front of the sea cliff.

If waves carve notches at a narrow point on both sides of a promontory on the rocky cliffed coast, a natural arch may be formed.

The best-known example in Germany is the Lange Anna on Heligoland, while, in England, a prominent example are Old Harry Rocks in Dorset.