Coastal Erosion

Coastal Erosion

1. Erosion Definition

   • When rocks are broken down into smaller particles and moved

2. Types of Erosian

   • Attrition
     • Loose particles hit against each other within the waves
   • Hydraulic Action
     • The force of waves compresses air in the cracks in rock along the coastline
   • Corrosion (Solution)
     • Salts and other acids in sea water dissolve calcium carbonates in the coastline
   • Abrasion (Corrasion)
     • Waves hurl fragments of rock against the coastline

3. How do waves shape the coastline

   • Waves are caused by the wind dragging the surface of the water.
   • FETCH
     • The distance of the water that the wind blows over

4. Processes of transportation

   • Traction
     • Material is rolled along the sea bed
   • Suspension
     • Loose particles in the water travel within the water
   • Saltation
     • Small particles bounce along the sea bed in a 'leap frog' movement
   • Solution
     • Particles dissolve and are carried within the water but cannot ne seen

5. How are beaches formed

   • Constructive waves transport material along the coast by longshore drift
     • The strong swash carries materials
       • The weak backwash deposits the bigger and heaviest material first, at the highest point of the beach
         • The weak backwash carries the smallest and lightest materials down and deposits it last, closest to the water
           • Over time more and more materials are deposited onto the land and a beach forms