Changing landscapes Flashcards
What is hydraulic action
The power of the waves forcing air into cracks, gradually increasing the pressure then the rock cracks or breaks apart
What is attrition
Rocks and pebbles carried by waves smash into each other, wearing each other away and gradually becoming smaller, rounder and smoother
What is abrasion
Process of rocks and pebbles carried by the waves wearing away the coasts as they are thrown against them
What is solution
When chemicals in the seawater dissolve minerals in the rock causing them to break up
What are the landforms of coastal erosion
Headlands, bays, caves, arches, stacks and stumps
Landforms created by deposition
Spits, salt marshes, beaches
What is solution (transportation)
When minerals in rocks like chalk and limestone are dissolved in sea water and carried in solution (load is not visible)
What is suspension (transportation)
Small particles are suspended in the flow of water
What is saltation (transportation)
When small pieces of sediment bounce along the sea bed
What is traction (transportation)
Where pebbles and larger material are rolled along the sea bed
Why does deposition occur
Sea loses energy, dropping the material it has been carrying. Occurs on coastlines that have constructive waves
Name 3 types of weathering
Freeze thaw, biological and chemical
What is biological weathering
Roots burrow down, weakening the structure of the rock until it breaks away
What is freeze thaw weathering
When rocks are porous (contain holes) or permeable (allow water to pass through) and water gets in the freezes due to drop in temp, causing it to expand cracking the rock
What is chemical weathering
Rainwater and seawater are slightly acidic causing them to dissolve rock like limestone and chalk
