Core Theme 1 - Coastal Landscapes Flashcards
When the sea hits the soft and hard rocks, the ___ rock erodes quicker and inwards forming a ___
The hard rock that erodes slower is called a ______
When the sea hits the soft and hard rocks, the soft rock erodes quicker and inwards forming a bay
The hard rock that erodes slower is called a headland
What is a bay?
A low-lying inlet of land on the coast
What is a headland?
A high area of land that extend out into the sea
What is a wave cut platform
A flat area in front of a cliff, just below the low tide mark. These were formed when the waves eroded the cliff, but left a flat platform behind.
Bays are more sheltered with ______ waves which ______ sediment to ____ a beach.
Bays are more sheltered with constructive waves which deposit sediment to form a beach.
What is a wave-cut notch?
An area of erosion at the base of a cliff formed by the waves.
How is a wave cut platform formed?
The sea attacks the base of the cliff between the high and low water mark.
A wave-cut notch (small scale landform) is formed by erosional processes such as abrasion and hydraulic action, this is a dent in the cliff usually at the level of high tide.
As the notch increases in size, the cliff becomes unstable and collapses, leading to the retreat of the cliff face.
The backwash carries away the eroded material, leaving a wave-cut platform.
The process repeats. The cliff continues to retreat.
Rock pools (a small scale landform) are left which often home a wide range of marine life as well as attracting many tourists.
How is an arch formed?
When the water erodes the soft rock it forms a cave, the cave becomes larger and eventually breaks through the headland to form an arc
How is a stack formed?
When the base of the arch continually becomes wider through further erosion, until its roof becomes too heavy and collapses into the sea. This leaves a stack
What are beaches made up of?
Eroded material that has been transported from elsewhere and then deposited by the sea
What type of waves build up beaches and why?
Constructive waves build up beaches because they have a strong swash and a weak backwash
Where are sandy beaches normally found?
Sandy beaches are usually found in bays where the water is shallow and the waves have less energy.
Where are pebble beaches found?
Pebble beaches often form where cliffs are being eroded, and where there are higher-energy waves.
What is a spit?
A stretch of beach at one end of a coastline caused by waves depositing material.
where do spits occur?
By the river mouth or if there is a change in landscape
Explain the formation of a spit
Sediment is carried by longshore drift.
When there is a change in the shape of the coastline, deposition occurs. A long thin ridge of material is deposited. This is the spit
A hooked end can form if there is a change in wind direction.
Waves cannot get past a spit, therefore the water behind a spit is very sheltered so silts are deposited here to form salt marshes or mud flats.
Where is Dorset located?
Dorset is located in the south of England. Its coastline has examples of large scale landforms
e.g Swanage is an example of a headland and bay
Old Harry Rocks is an example of stacks
What is a discordant coastline and give an example
Where the are bands of soft and hard rock and it alternates in between. An example is the area around Swanage
What is a concordant coastline
Has the same type of rock across its length
Where are Old Harry Rocks located?
Old Harry Rocks are located on the headland between Swanage and Studland Bay.
What is Old Harry Rock made of?
It’s made of chalk, a hard rock
How has human interference affected Criccieth?
The cliffs and bays have changed shape
At the Western Beach, where the groynes are located, deposits of sand and shingle on the one side of the groyne are almost 1.5 metres higher than the other side. This has altered the appearance of the beach and accelerated erosion on the Eastern Beach, which is now starved of sand due to the groynes.
Longshore drift is interrupted so which causes the Eastern Beach to starve of sand
