Coasts Flashcards
What do waves erode cliffs to form?
wave-cut platforms
Where do waves cause the most erosion?
foot of a cliff
Explain the process of a wave-cut platform?
- erosion occurs at foot of cliff
- wave cut notch formed and erosion continues
- rocks above notch become unstable and collapse
- collapsed material is washed away and new notch forms
- as the process repeats, cliff retreats
Explain the process of headlands and bays?
- form when alternating band of resistant and less resistant rock are along the coast
- less resistant rock is eroded quickly by water, forming a bay ( gentle slope)
- hard resistant rock is eroded more slowly and is left jutting out, forming a headland ( steep side)
What happens to soft rock?
easily eroded
What happens to hard rock?
harder to erode with solid structure
What can headlands be eroded to form?
caves, arches and stacks
What do headlands have that mean they can form caves arches and stacks?
resistant rock with weaknesses like cracks
Explain how caves arches and stacks are formed?
- waves crash into headlands and enlarge the cracks by hydraulic power and erosion
- repeated erosion and enlargement of cracks form caves
- continued erosion deepens the cave until it breaks through the headland forming an arch
- erosion con tines and wears away the rock supporting the arch, until it collapses
- a stack is formed
What is a stack?
an isolated rock that’s separate from the headland
What is hydraulic power?
waves crash against rock and compress air in cracks, puts pressure on ricks, repeated compression widens cracks and bits fall off
What is abrasion?
eroded particles in the water scrape and rub against rock, removing small pieces
What is attrition?
eroded particles in the water smash into each other and break into smaller fragments
What is transportation?
movement of material
What is the process that transports material along the coats?
longshore drift
