Coasts Flashcards
What is mechanical weathering?
When rocks disintegrate or break up without experiencing any change in their chemical composition,
What is Mechanical weathering also know as?
Physical weathering
What is the most common type of mechanical weathering?
Freeze thaw weathering
How does freeze thaw weathering work?
First water collects on gaps in the rock, over night the temperature falls and water turns into ice. Ice is larger than water and this forces the gap to widen.
Chemical weathering is caused by
chemicals in the rain or in the sea water, these chemicals breakdown the rock washing it away
What is Hydrolysis?
Hydrolysis is the wearing away of the rocks by the acid rain.
What is mass movement?
Mass movement is the downhill movement of sediment that moves because of gravity. It falls from the cliff onto the beach below.
Can you name the four different types of mass movement?
Rock fall: Bits of rock fall of the cliff, usually due to freeze thaw weathering.
Landslide: Large blocks of rock slide downhill.
Mudflow: Saturated soil flows down a slope.
Rotational slip: Saturated soil and weak rock slump down a curved surface.
How many wave types are there?
They’re two types constructive waves and destructive waves
Tell me characteristics of a destructive wave.
.The swash is weaker than the backwash
.The strong backwash removes sediment from the beach.
.The waves are steep and are close together.
Tell me characteristics of a constructive wave.
. Strong swash and weak backwash.
.The strong swash brings sediment to build up the beach.
.The backwash is not strong enough to remove the sediment.
.The waves are low and further apart.
What is a swash?
A swash is the water that rushes up the beach
What is a backwash?
The water that flows backward toward the sea.
What is longshore drift?
Longshore drift is the movement of material, due to the angled approach of waves
What id deposition?
Deposition is when the sea looses energy and drops the material its been carrying.
What are factors that lead to deposition?
.Waves starting to slow down and loose energy
.Shallow water
.Sheltered areas eg bays
.Little or no wind.
What is erosion?
Erosion is the wearing away of rock along the coastline.
There are four types of erosion. Name them
Hydraulic action
Abrasion
Attrition
Solution
What is hydraulic action?
Hydraulic action is the sheer power of the waves as they smash against the cliff. Air becomes trapped in the cracks and causes the rock to break apart.
What is abrasion?
Abrasion is when pebbles grind along a rock platform, much like sandpaper. Overtime the rock becomes smooth.
What is attrition?
Attrition is when rocks that the sea is carrying knock against each other. They break apart to become smaller and rounded.
What is solution?
Solution is when sea water dissolves certain types of rocks. In the UK chalk and limestone cliffs are prone to this type of erosion.
Concordant coastlines
Concordant coastlines means that the bands of rock line up in the same direction as the coastline.
