Module 7 of 12 · Text
Coastal Processes
- Waves
- Constructive - build up the beach, strong swash and weak backwash
- Destructive -destroy the beach, weak swash and strong backwash
- Freeze-thaw Weathering
- Water enters rocks
- It freezes
- Ice melts and goes deeper into the rock
- Happens many times and the cracks become bigger
- Biological Weathering
- Roots enter rocks
- Roots grow and make them wider
- Rock breaks away
- Chemical Weathering
- Acid in the rain and sea water dissolve the rocks
- Hydraulic Action - waves smash against the cliff causing it to breakdown
- Abrasion - pebels grind agaisnt each other and become smooth
- Attrition - rocks knock against each other causing them to break up
- Solution - sea water dissolves rocks
- Solution - dissolved materials are carried in the water
- Suspension - small rocks flow with the water
- Saltation - small rocks bounce along the sea bed
- Traction - larger rocks roll along the sea bed
- Longshore Drift
- Waves approach the sea at an angle due to the prevailing winds
- Swash carries material onto the beach
- This repeats in a zig zag formation causing a material build up
- Deposition - when waves drop materials onto the beach