Geography- Coasts

Abrasion/corrasion

Fragments of rock are picked up and hurled at the cliff by the sea. They scrape and gouge the rock

hydraulic action

Strong waves crash into the cliff face blasting trapped air into holes and cracks in the rock causing them to break apart

attrition

rock fragments carried by the sea knock into each other, they break down and become smaller and more rounded

Solution/corrosion

chemical action of sea water where. salts and acids in water can dissolve rock

3 agents of erosion

wind, ice and water

weathering

breaking down of rocks in situ

2 types of waves

tidal and wind driven waves/surface waves

what are the 3 ways that waves differ in size?

fetch, wind strength and wind duration

fetch

distance of water the wind blows over

Wind strength

the speed the wind is blowing

wind duration

the amount of time wind is blowing

wave length

distance between 2 crests

crest

top of the wave

trough

bottom of the wave

wave height

distance between top and bottom of the wave

What happens when waves go towards headlands

they converge, increase in height and energy and more erosion occurs

what happens when waves go towards bays

they diverge, decrease in height and energy and more deposition occurs

swash

movement of water up the beach after a wave breaks

backwash

movement of water flowing back down the beach and returns to the sea