Coasts Flashcards
What is the case study example for wave cut platform?
Southerndown, South Wales
What is the case study example for cave, arch, stack and stump?
Old Harry Rocks, Dorset
What are the steps to forming a wave cut platform?
1) Weather weakens the top of the cliff
2) The sea attacks the base of the cliff forming a wave cut notch
3) The notch increases in size, and the cliff collapses
4) The backwash carries the sediment toward the sea forming s wave cut platform
5) Process continues as the cliff continues to retreat
What are the steps to forming a cave?
1) The sea erodes away at the headland and the bottom crumbles off, original fault lines
2) The sea erodes it with abrasion and hydraulic action which makes a cave as its being eroded from one side
How is an arch formed?
After a cave is formed, weathering and erosion has broken through the cave to make and unstable arch- from both sides
How is a stack and stump formed?
The bottom of the arch cant hold its weight and vegetation breaks through the rock so it collapses and forms a stack
These stacks have 360 degrees of attack from the sea and form stumps
What is the case study example for a headland and bay?
Swanage, Dorset
What is the case study example for soft rock slumping?
Cliffs of Norfolk
What are the steps to forming a headland and bay?
1) Three strips of land- hard rock, soft rock, hard rock
2) Sea erodes all parts of the cliff
3) The soft rock erodes faster than hard rock, it retreats
4) Retreated soft rock cliffs form an arc shape called the bay, and the headlands are the cliffs sticking out to sea
5) Caves, arches, stacks and stumps starts to form
What are the five factors that cause soft rock slumping?
- Base of the cliff is eroded
- Weathering weakens the rock
- Heavy rain saturates the cliff top and adds weight
- Water flows through permeable rock and erodes it
- Building on the top of the cliff adds weight, pushes down on the weak cliff
What is the case study example for a spit?
Easthead Spit, Hampshire
What is the case study example for a bar?
Slapton Key, Devon
What are a positive and negative effect of longshore drift, for named locations?
Easthead Spit- 90m wide beaches protect settlements being flooded, tourist attraction, protected habitats for animals
Clarence Pier- 2m left of beach, lowered income from tourism, land behind beach has to rely on manmade methods of coastal management to protect land
What are the steps to longshore drift?
1) The prevailing winds hit the sea at an angle and the waves are at that angle
2) Causes the swash to be at and angle to the sea, and the deposition is at the side
3) However the backwash brings it back at 90 degrees to the sea, makes a zig zag
4) Constructive waves moves the sediment across the shore, so sediment deposition is moved from one end of the coast to the other, in the prevailing wind direction
What are the steps to forming a spit?
1) Longshore deposits sand and shingle to one side of the coast, by the headland
2) As it gets to the end it keeps building up at the headland, the prevailing wind direction changes so longshore drift changes direction and forms a recurved edge
3) Between the recurved edge and headland, sea water gets trapped and creates a salt marsh