Coastal Landscapes in the UK - key words Flashcards
Hydraulic action
Air is smashed into the cracks b the power of the water. Cracks expand and rocks weaken and eventually break.
Abrasion
Rocks hit the bottom of a cliff and break it causing the clif to collapse and a wave cut platform is formed.
Attrition
Attrition is when rocks constantly hit against eachother they break eachother down. Rocks can also make rocks smaller, rounder and smoother.
Corrosion (solution)
Sea water is very corrosive and can slowly dissolve chalk and limestone, which makes the size of cracks/joints bigger so that more erosion can take place.
Wetting and Drying
Softer rocks such as clay can get bigger (expand) when they are wet and then get smaller (contract) when they dry out. This can make the rock weaker so they erode more easily.
Erosion
There are three examples of this:
- Abrasion
- Attrition
- Hydraulic action
Constructive waves
These types of waves create beaches.
Destructive waves
These types of waves destroy beaches.
Swash
This is when material in the wave is washed up the beach.
Backwash
This is when material in the wave is washed back down the beach.
Transportation
This is when material is transported in the wave.
Deposition
This is when material is deposited (dropped) by the wave.
Discordant coastlines
These have alternating layers of rock at right angles to the coast.
Concordant coastlines.
These have alternating layers of rock that are parallel to the coast.
Wave frequency
The number of waves breaking per minute.
Crest
The top of a wave.
Wave height
The vertical distance from trough to crest.
Trough
The base of a wave.
Wave length
The horizontal distance between two successive crests.
Hold the line
Maintain the existing coastal defences.
Advance the line
Build new defences further out to sea than the existing ones.
Do nothing
Build no coastal defences at all and deal with the consequences as it happens.
Retreat the line
Build no coastal defences, but move people away from the coast.
Hard engineering
Man - made structures built to control the flow of the sea and reduce flooding and erosion.