Coasts Flashcards
How are spits formed?
A prevailing wind hits the beach at an angle so that the waves travel in at a different angle and longshore drift occurs at a different angle, pulling the beach out into the ocean
Salt marshes can form in the area behind a spit
What are spits?
An extended stretch of beach that projects into the sea and is attached to the mainland on only one side
How is a hooked spit formed?
The same as a normal spit but the prevailing wind changes direction slightly once the spit has already started to form, giving a hooked shape to the spit
What is a tombola?
A spit which joins to another part of mainland on its other side
The area of water behind a tombola can create a lagoon
Features of a destructive wave
- created in storm conditions
- short wavelength but high amplitude
- have travelled over long distances
- more backwash than swash
- destroy/break down the beach
Features of a constructive wave
- created in calm conditions
- deposit material & build up beaches
- have a long wavelength and low amplitude
How are caves formed?
Waves attack the headland cliffs and force their way into cracks. They continuously break away these cracks into bigger and bigger holes until a cave is formed
The predominant process is hydraulic action
How are arches formed?
Waves break away caves until the caves reach the other side of the cliff
A cave that passes through a hole cliff and reaches the other side is called an arch
How are stacks formed?
An arch becomes so wide that it cannot support the weight of the cliff above so it collapses to leave the headland cliff on one side and a stack of cliff alone in the sea
How are stumps formed?
Stacks are eroded away by the power of the ocean to leave damaged, smaller and worn down stacks: called stumps
