Coastal Depositional Landforms: Beaches

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Beaches Beaches are mainly constructed of sand and shingle.

Ridges and Runnels form when the sand becomes compact when its wet and the backwash carries material down the beach. Ridges and Runnels run parallel to the shoreline and are broken by channels that drain.

Spring tides often form a storm beach which consists of the largest material thrown up by the strong swash of the larger waves. Following tides often cannot reach these features therefore they remain largely untouched.

There are often a series of smaller ridges formed beneath the storm ridge known as berms. These mark the successive high tides that follow the spring tide through to the neap tide.

Cusps are crescent-shaped indentations that form on beaches of mixed sand and shingle. They are formed where there is a junction between sand and shingle. Once the curving shape is created, swash is concentrated in the small bay that forms in the centre of the cusp. This creates a stronger backwash that removes material down the beach.

Below the cusps, ripples are developed on the sand by wave action or tidal currents.