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How does wind affect coastlines?

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Key points

  • Coastlines are shaped by a number of processes such as , and .
  • These processes can lead to a number of different types of landforms such as caves, arches, stacks and stumps.
  • Different types of landforms are caused due to several influences such as the geology of the coast.

Game - Erosion

Play a Planet Planners mission to help locals, tourists, plants and animals deal with erosion.

You can also play the full game

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Landforms activity

Learn more about how coastlines are formed with this activity.

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Coastal processes

Video: Coastal processes and landforms

Learn about coastal processes and landforms

The of a coastal region is formed as a result of various processes:

  1. Rocks are eroded.
  2. Then, the sediment that comes off is transported.
  3. Finally, the sediment is deposited elsewhere.

1. Erosion

Erosion is when the rocks are worn away, in this case by the action of waves. There are several different processes of erosion:

Hydraulic action/powerWhen waves crash against a cliff, they force air into cracks in the rock. The force of this trapped air causes the rock to weaken and eventually break.
Abrasion/corrasionThis is where being carried by the water wears away the surface, almost like sandpaper.
SolutionChemicals in the water dissolve certain types of rock such as limestone. However, there is some debate about how much coastal erosion this causes.
AttritionRocks crashing into each other result in them becoming smoother and more rounded.

2. Transportation

Sediment in the water will be transported. This happens in four different ways:

  • suspension - lighter material floats within the water
  • traction - larger rocks roll along the sea bed
  • solution - some material, such as chalk, gets dissolved into the water
  • saltation - smaller rocks, if they are too heavy to be suspended, hop along the sea bed
Four types of transportation: suspension, traction, solution and saltation
Figure caption,
Different ways sediment can be transported in the sea

3. Deposition

When waves carrying sediment reach the shore, they will deposit it in areas where they lose energy - often in sheltered areas such as bays. This can lead to the formation of beaches. Sometimes the waves will continue to move sediment along the beach. The direction this is moved in will depend on the . If the wind is coming in at an angle, then the waves will also move up and down the beach at an angle. This causes the sediment to be moved in a zig-zag pattern. This is called .

Question

Name the four processes of erosion.

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Quiz: Coastal processes

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Coastal landforms

Geology

The of a coastline influences the landforms we see there. Some rocks are harder than others and so are more resistant to erosion. For example, rocks such as granite are hard and erode much more slowly than softer rocks, such as boulder clay or shale.

Examples of coastal landforms

Question

If a spit connects an island to the mainland (a headland), what landform is formed?

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Quiz: Coastal landforms

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Formations

How a stump is formed

Image gallerySkip image gallerySlide 1 of 5, , Cracks at the base of the headland become exposed through hydraulic action/power, which pressurises air, forcing the crack to widen.

Question

If the roof of an arch collapses, what landform is formed?

How a spit is formed

Formation of spit
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Quiz: Formation of a spit

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Play the Planet Planners game! game

Make decisions for the planet in this KS3 geography game.

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More on Coasts

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