The coastal zone: key processes
Three key processes take place in the coastal zone:
- Erosion - waves can erode the coastline in a similar way to the water in rivers. This usually occurs when the sea takes lots of energy from the power of Waves which remove material from the beach. The swash is weaker than the backwash. waves.
- Transportation - the movement of eroded material up and down, and along the coast.
- Deposition - when the sea loses energy, it drops the sand, rock particles and pebbles that it has been carrying, depositing them.
Four key factors affect the erosion of the coastline:
- Rock type - chalks and limestone can form Steep exposed rock face., whereas clays and softer rock form large A low-lying inlet of land on the coast..
- Rock structure - a discordant coastline, where rocks are at an angle to the edge of the coastline, will erode at different rates.
- The shape of the coastline - headlands of a coastline are exposed to the full force of destructive waves. Bays are more sheltered from the wave energy because of The process where a wave changes direction as it approaches the shore., so erosion is slower.
- The type of wave - the amount of energy a wave has helps determine the rate of erosion.
Deposition is likely to occur when:
- waves enter an area of shallow water
- waves enter a sheltered bay
- there are calm conditions with little wind