Coasts Flashcards
(37 cards)
What is a fetch
The distance of open water which the wind blows
What is a beach
A deposit of sand or shingle at the coast often found at the head of a bay
What is a crest?
The top of a wave
What is a backwash
The backward movement of water down a beach when a wave has broken
What is a constructive wave
A powerful wave with a strong swash that goes up the beach
What is a destructive wave
A wave caused by a local storm that crashes down onto a beach and has a powerful back wash
What is hydraulic power?
The power of the waves as they smash into the cliffs. Trapped air is blasted into the holes and cracks in the rocks eventually causing the rock to break.
What is cavitation?
Explosive force of trapped air operating into a crack.
What is corrasion?
Fragments of rock being picked up by the waves and thrown by the sea at the cliff. Scrapes and erodes the rock away at the bottom of the cliff.
What is abrasion?
Sandpapering effect
Pebbles grinding on a rocky platform causing it to become smooth
What is solution?
Limestone and chalk being dissolved by the sea water. Causing cliffs.
What is attrition?
Where rock fragments are carried by the sea and knock against each other causing them to become smaller and more rounded
What is suspension
Transportation
Particles which are carried in the water
What is traction
Transportation
Large pebbles which are rolled along the sea bed
What is saltation
Transportation
Hopping or bouncing of pebbles along the sea bed which are too heavy to roll.
What is a swash?
Waves carry sediment up the sea at a 45 degree angle.
What is a backwash?
Sediment carried back down the beach as the wave draws back at a right angle.
What is longshore drift?
The movement of material along a coast by waves.
What is a wave cut notch/platform
The narrow flat area found at the base of a sea cliff which is created by the erosion of waves.
What is mass movement?
Where rain water seeps through the land and saturates it. It can no longer hold its shape and a landslide occurs.
Holbeck hall in Scarborough
Especially happens in areas with softer clay such as bolder clay
What is sliding?
A plane of weakness gives in due to Gravity and the rock slides down into the sea.
They are huge and very dangerous.
What is slumping?
Removal of the base of the cliff removes support for the rock above.
This makes the rock slump down
Leaving a long curved plane of weakness.
How is a beach formed?
They are formed in the bays due to constructive waves.
How is a bay formed?
A bay is formed in the softer rock
Waves refract onto headlands producing destructive waves.
