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Coastal processes - AQATransportation

Processes called erosion, mass movement and weathering break down and remove material from the coast. The material is moved along the coastline by the sea and deposited when there is energy loss.

Part of GeographyCoastal landscapes in the UK

Transportation

Beach material can be moved in four different ways. These are:

  • Solution - when minerals in rocks like chalk and limestone are dissolved in sea water and then carried in solution. The load is not visible.
  • Suspension - small particles such as silts and clays are suspended in the flow of the water.
  • Saltation 鈥 where small pieces of shingle or large sand grains are bounced along the sea bed.
  • Traction 鈥 where pebbles and larger material are rolled along the sea bed.

Sediment is carried by the waves along the coastline. The movement of the material is known as . Waves approach the coast at an angle because of the direction of prevailing wind. The will carry the material towards the beach at an angle. The then flows back to the sea, down the slope of the beach. The process repeats itself along the coast in the zigzag movement.

Waves approach a beach at an angle - determined by prevailing wind direction. Waves push rocks up the beach, roll back down and are pushed back up in a zig-zag pattern.