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There are different kinds of landform. Examples are:

Wave-cut platform

Wave energy is at its maximum when a high, steep wave breaks at the foot of a cliff. This results in undercutting of the cliff to form a wave cut notch. The continual undercutting causes increased stress and tension in the cliff until it eventually collapses. As these processes are repeated the cliff retreats, leaving a gently sloping wave cut platform which has a slope angle less than 4⁰. The platform, which appears relatively even when viewed from a distance, cuts across rocks regardless of their type and structure. A closer inspection of this intertidal feature usually reveals that it is deeply dissected by abrasion, resulting from material carried across it by tidal movements, and corrosion. As the cliff continues to retreat then the widening of the platform means that wave break further out to sea and incoming waves have to travel over a wider area. This will dissipate their energy, reduce the rate of erosion of the headland and limit the further extension of the platform. It has been hyothesised that wave cut platforms cannot exceed 0.5 km in width.

Where there has been negative change in sea level, former wave cut platforms remain as raised beaches above the present influence of the sea.

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Caves, blowholes, arches and stacks  

Where cliffs are of resistant rock, wave action attacks are lines of weakness such as points and faults. Sometimes the sea cuts inland along a joint to form a narrow, steep sided inlet called a geo, or to undercut part of the cliff to form a cave. As shown in Figure 6.16, caves are often enlarged by the combined processes of marine erosion. Erosion may be vertical, to form blowholes, but is more typically backwards through a headland to form inches and stacks.

These landforms, which often prove to be attractions to sightseers and mountaineers, can be found at the Needles (Isle of Wight), Old Harry (near Swanage) and Flamborough Head (Yorkshire), which are all cut into chalk, and at the Old Man of Hoy (Orkneys) which is Old Red Sandstone.

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Bars and Tombolos

 If a spit extends across a bay linking two headlands, straightening the coastline, it is called a bar. When a spit or bar joins the mainland to an island it is a tombolo. Chesil Beach, off the Dorset coast, presents a gently smoothing face 30 km long and up to 14 m high to the prevailing winds in the English Channel and links the Isle of Portland to the mainland.

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