Coasts Coastal Erosion Date Today I will Know the key terms Know how a bay and wave cut platform is formed Geography Coasts Processes of Erosion at the Coastline 1 Hydraulic Action ID: 219996
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Slide1
Geography
Coasts
Coastal Erosion [Date]
Today I will:
Know the key terms
Know how a bay and wave cut platform is formed Slide2
Geography
Coasts
Processes of Erosion at the Coastline
1. Hydraulic Action:
Waves crash against a cliff and drive water under great pressure into cracks in the rock. This pressure squeezes the air and as the wave falls back the air expands explosively, loosening pieces of rock.
2.
Corrasion
:
Corrasion
(or abrasion) occurs when stones and pebbles are picked up by waves and thrown against the cliff, causing erosion.
3
.
Solution:
Salty sea water chemically dissolves rocks. This is most noticeable on chalk and limestone cliffs
.
4.
Attrition:
Rock fragments (stones and pebbles) hit against each other and so are reduced in size.Slide3
Geography
Coasts
Backwash:
As the wave loses its momentum, energy is transferred back to the sea – this return flow is called
backwash.
Swash
:
The water which rushes up the beach is called
swash
.
The force of the swash and backwash determines whether the waves are
constructive waves
or
destructive waves.Slide4
Geography
Coasts
If the swash is weaker than the backwash
(destructive wave),
very little
material
is carried up the beach. With a strong backwash, material will be removed and the beach will decrease in
size.Slide5
Geography
Coasts
Wave-cut platform
CliffSlide6
Geography
CoastsSlide7
Geography
CoastsSlide8
Geography
Coasts
Bay
HeadlandSlide9
Geography
CoastsSlide10
Geography
CoastsSlide11
Geography
CoastsSlide12
Geography
Coasts