4.3 Coastal Landforms Flashcards
(27 cards)
What are joints
either a layer or body of rock that lacks any visible or movement parallel to the surface of the fracture.
What are headlands and bays
Are when a cliffside of soft rock and hard rock erode but due to the soft rock eroding faster, the soft rock will become a bay and the hard rock will become a headland.
What is concordant
Where the coast is one type of rock eg all hard rock
What is discordant?
A coastline which is all different types of rocks eg both hard and soft rock.
What are faults?
Faults have a relative movement and show displacement. This means that they are a rock formation.
Hard rocks?
Chalk, limestone, obsidian and more.
Soft rocks?
Clay and sand
How are caves made?
Caves occur when the waves force their way into cracks in the cliff face. The water contains sand and other materials that grind away at the rock until the cracks become so big it becomes a cave.
How are arches made?
If a cave is formed in a headland, it may eventually break through to the other side which will create an arch structure.
How are stacks made?
Stacks are made when the arch erodes away more until it cannot withstand itself and drops leaving only a stack remaining.
Wave cut platforms?
Destructive waves will crash into the coast and will erode away the top half of the cliff first and it will leave a wave cut platform formation.
Why are prevailing winds important?
It can create a long shore drift with the way that the waves are going.
What are the differences between destructive and constructive waves?
Destructive erode away object at a faster rate and hit the coast with more power causing abrasion, attrition, hydraulic action and more while constructive waves will cause erosion at a slower rate and they tend to affect beaches more than cliff sides.
What is longshore drift?
It is when the prevailing wind and wave winds go at different direction meaning the movement of the sediment on the beaches slowing moving across the coast.
What is deposition?
Where sediment from a different area moves over to a place such as a spit and makes new formations.
What are spits?
Spits are when longshore drift moves sediment far enough to get to an edge where the sediment will pile up and make a spit.
What are the factors of wave energy?
how long the wind has been blowing
the strength of the wind
how far the wave has travelled
Where are the biggest waves?
In Cornwall because it has a lot of cliffs on the seaside which will mean that the land will not get smaller breaking the waves apart. Also it is because of the Atlantic ocean.
Abrasion
When rocks smash into the cliffside from the waves.
Hydraulic action
When the power of the waves break the cliffside.
Attrition
When tougher, harder rocks smash together and become smoother.
Solution
Acids on the sea will erode away the cliffside.
Freeze-thaw
This is where the water gets into cracks in the cliff and will solidify in the cliff and expanding making the cliffs cracks bigger.
Explain a Bar.
A bar is very similar to a spit. It is a ridge of sand or shingle which forms across the mouth of a river, the entrance to a bay or harbour. It is usually parallel to the coast.
