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Wave Action

Coastal Processes
What is coastal erosion?
What is coastal transportation?
What is coastal deposition?

Erosional Landforms
Cliff Recession
Landforms overview
Bays and headlands
Erosion Of A Headland

Deposition Landforms

Salt Marshes
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Coastal Management
Why defend the coast?
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Soft Engineering Techniques

Case Study
The Holderness Coast

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Coastal Processes

Online Activities
[Online activities]: n Activities related to this topic
Coastal Erosion - Match up game
Waves - Match up game
Coastal Deposition - Match up game
Coasts Interactive revision diagram
Coastal Processes - Quiz
Coastal Erosion Landforms - Quiz
[Podcast]: n Audio file for playback on mobile devices and personal computers
Waves and Coastal Erosion 
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View images of coastal environments in the coastal gallery.
View videos of coastal environments in the video gallery.


There are three main processes at work in the sea. These are erosion, transportation and deposition.

What is coastal erosion?

Erosion is the wearing away of the land by the sea. This often involves destructive waves wearing away the coast.
There are five main processes which cause coastal erosion. These are corrasion, abrasion, hydraulic action, attrition and corrosion/solution.

Corrasion is when waves pick up beach material (e.g. pebbles) and hurl them at the base of a cliff.

Abrasion occurs as breaking waves which contain sand and larger fragments erode the shoreline or headland. It is commonly known as the sand paper effect.

When waves hit the base of a cliff air is compressed into cracks. When the wave retreats the air rushes out of the gap. Often this causes cliff material to break away. This process is known as hydraulic action.

Attrition is when waves cause rocks and pebbles to bump into each other and break up.

Corrosion/solution is when certain types of cliff erode as a result of weak acids in the sea.

You can view animations of each of these processes here (this will open in a new window/tab).

You can find out about the landforms created as the result of coastal erosion here.

What is coastal transportation?

Transportation is the movement of material in the sea and along the coast by waves. The movement of material along the coast is called longshore drift.

What is Longshore Drift?

Longshore drift is the movement of material along the shore by wave action.

Image of longshore drift

Longshore drift happens when waves moves towards the coast at an angle. The swash (waves moving up the beach) carries material up and along the beach. The backwash carries material back down the beach at right angles. This is the result of gravity. This process slowly moves material along the beach. Longshore drift provides a link between erosion and deposition. Material in one place is eroded, transported then deposited elsewhere.

How does the sea transport material?

Although longshore drift is the main process of transportation the material moves in four different ways. These are:

Traction - large material is rolled along the sea floor.

Saltation - beach material is bounced along the sea floor.

Suspension - beach material is suspended and carried by the waves. .

Solution - material is disolved and carried by the water.


Deposition is when eroded material is dropped by constructive waves. It happens because wave have less energy. Deposition creates a range of landforms. You can find out more on the depositional landform geotopic.

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