Coastal: Points for Coastal Erosion Features Flashcards
Hydraulic Action GO!
Hydraulic action is when the sheer force of the waves enters cracks in the rocks, compressing the air and forcing pieces of rock to break off
What is Abrasion?
Abrasion is when rocks carried by the water are thrown against the cliff, causing abrasive action, wearing away the rock.
WCP: How are wave cut notches formed?
Weakness such as joints or cracks in the cliff are undercut by erosion to form a wave-cut notch.
WCP: Ok so think waterfalls…overhanging and collapsing….
The rock above overhangs over the notch (1) Then the unsupported overhang collapses due to the weight and gravity. (1)
WCP: How are wave-cut platforms formed? Retreating, gently-sloping, extends out to sea.
The cliff retreats inland, leaving a gently-sloping rocky surface known as a wave-cut platform which extends out to sea away from the cliff.
Headlands and Bays: What does differential erosion cause
Differential erosion causes soft rock to be eroded quicker than hard rock
Headland and Bays: Where do they form?
They are formed on discordant coastlines where alternate bands of rock are found at right angles to the coast.
Headlands and Bays: What are Headlands?
Headlands are areas of hard rock which jut out to the sea
Headlands and Bays: What are Bays?
A bay is a sheltered area of softer rock between the headlands
What is an example of a Stack?
Old Harry
How are stacks formed from arches? (again, think waterfalls.)
The base of the arch is undercut by erosion, causing the arch to become unsupported (1). Eventually the arch collapses due to gravity to form a stack. (1)
