A wave-cut platform, shore platform, coastal bench, or wave-cut cliff is the narrow flat area often found at the base of a

sea cliff A cliffed coast, also called an abrasion coast, is a form of coast where the action of marine waves has formed steep cliffs that may or may not be precipitous. It contrasts with a flat or alluvial coast. Formation In coastal areas in whic ...

or along the shoreline of a

lake A lake is often a naturally occurring, relatively large and fixed body of water on or near the Earth's surface. It is localized in a basin or interconnected basins surrounded by dry land. Lakes lie completely on land and are separate from ...

, bay, or

sea A sea is a large body of salt water. There are particular seas and the sea. The sea commonly refers to the ocean, the interconnected body of seawaters that spans most of Earth. Particular seas are either marginal seas, second-order section ...

that was created by erosion. Wave-cut platforms are often most obvious at low tide when they become visible as huge areas of flat rock. Sometimes the landward side of the platform is covered by sand, forming the beach, and then the platform can only be identified at low tides or when storms move the sand. __TOC__

Formation

Wave-cut platforms form when destructive waves hit against the cliff face, causing an undercut between the high and low water marks, mainly as a result of abrasion,

corrosion Corrosion is a natural process that converts a refined metal into a more chemically stable oxide. It is the gradual deterioration of materials (usually a metal) by chemical or electrochemical reaction with their environment. Corrosion engine ...

and hydraulic action, creating a wave-cut notch. This notch then enlarges into a cave. The waves undermine this portion until the roof of the cave cannot hold due to the pressure and freeze-thaw or biological weathering acting on it, and collapses, resulting in the cliff retreating landward. The base of the cave forms the wave-cut platform as attrition causes the collapsed material to be broken down into smaller pieces, while some cliff material may be washed into the sea. This may be deposited at the end of the platform, forming an off-shore beach. Because of the continual wave action, a wave-cut platform represents an extremely hostile environment and only certain

organism An organism is any life, living thing that functions as an individual. Such a definition raises more problems than it solves, not least because the concept of an individual is also difficult. Many criteria, few of them widely accepted, have be ...

s can utilize such a niche.

Use of ancient examples

Ancient wave-cut platforms provide evidence of past sea and lake levels. Raised and abandoned platforms, sometimes found behind modern beaches, are evidence of higher sea levels in the geological past, and have been used to identify areas of isostatic adjustment. By using scientific dating methods, or examination of marine fossils found on the platform, it is possible to work out when the platform was formed, thus giving geographers and geologists information about sea levels at known times in the past. This has been used in the United Kingdom and other previously glaciated areas to calculate the rate at which land is rising now that it is no longer covered in ice. Where the coastline itself is changing due to seismic action, there may be a series of platforms showing earlier sea levels and indicating the amount of uplift caused by various

earthquake An earthquakealso called a quake, tremor, or tembloris the shaking of the Earth's surface resulting from a sudden release of energy in the lithosphere that creates seismic waves. Earthquakes can range in intensity, from those so weak they ...

Usage of term 'wave-cut'

According to Trenhaile, Sunamura, and Massalink and Hughes, the term 'wave-cut platform' should no longer be used as it assumes that shore platforms are the result of wave action, which is not always true. Shore platforms, like comparable river and lake platforms, are erosional features that develop when removal of saprock and other debris by waves and currents leaves behind a bedrock surface below the water table.Retallack, G.J. and Roering, J.J. 2012: Wave-cut or water-table platforms of rocky coasts and rivers? GSA Today 22(6), 4-9. File:BleikRaisedBeach&Platform.JPG, Raised beach and shore platform, Bleik, Norway File:WaveCutPlatformsAntelopeIslandUT.jpg, Shore platforms from Lake Bonneville (

Pleistocene The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...

), Utah, United States File:St bees head fleswick bay wave cut platform.JPG, Shore platform at St Bees Head, UK File:Tedbury Camp unconformity.JPG, Jurassic wave-cut platform at Tedbury Camp, southern England File:Austinmer, NSW - Brickyard Point, from the north, near boat ramp.jpg, Commonly called a 'rock platform' in Australia, these two examples at Austinmer, N.S.W, are typical of many on the coast of south-eastern Australia. File:Sydney (AU), Long Reef Headland -- 2019 -- 2786.jpg, The rock platform at Long Reef, N.S.W., Australia. File:Wave cut notch and submerged wave-cut platform, Elet Island, Busuanga, Palawan, Philippines.jpg, Wave-cut notch and submerged platform in Elet Island, Busuanga, Palawan, Philippines

References

{{DEFAULTSORT:Wave-Cut Platform Coastal geography Coastal and oceanic landforms

Formation

Use of ancient examples

Usage of term 'wave-cut'

See also

References