Coastal landforms Flashcards
The process of _______ can create different landforms along the coastline.
Erosion
Cliffs along the coastline do not erode at the same pace.
When a stretch of coastline is formed from different types of rock, __________ and _____ can form.
Headlands, bays.
Bands of ____ rock such as clay and sand are _______ and therefore they can be eroded quickly.
Soft, weaker.
How are bays formed.
When soft rock such as clay and sand erodes quicker
What is a bay.
A bay is an inlet of the sea where the land curves inward, usually with a beach.
How are headlands formed?
Hard rock such as slate is more resistant to the processes of erosion. When the softer rock is eroded inwards, the hard rock sticks out into the sea, forming a headland.
What erosional features can be found on headlands?
Wave-cut platforms and cliffs.
Bays are more sheltered with ___________ waves which deposit sediment to form a beach.
Constructive
How are cliffs formed?
Cliffs are shaped through erosion and weathering. Soft rock erodes quickly and forms gentle sloping cliffs. Hard rock is more resistant and forms steep cliffs.
What is a wave-cut platform?
A wave-cut platform is a wide gently-sloping rocky surface found at the foot of a cliff.
How is a wave cut platform formed?
The sea attack the base of the cliff between the high / low water mark.
A wave-cut notch is formed by erosional processes such as abrasion and hydraulic action, (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.
Caves, arches, stacks and stumps are erosional features that are commonly found on a __________
Headland
What is the order of the formation of cracks, caves, arches, stacks and stumps?
1 Crack
2 Cave
3 Arch
4 Stack
5 Stump
How are cracks formed?
Cracks are formed in the headland through the erosional processes of hydraulic action and abrasion.
How are caves formed?
As the waves continue to grind away at the crack, it begins to open up to form a cave.
How are arches formed?
The cave becomes larger and eventually breaks through the headland to form an arch.
What and how is a stack made?
The base of the arch continually becomes wider through further erosion, until its roof becomes too heavy and collapses into the sea, leaving a stack (an isolated column of rock)
How are stumps made?
The stack is undercut at the base until it collapses to form a stump.
How is a beach formed
Formed when material that has been transported and deposited builds up along the coastline
What is transportation
The movement of sand, sediment, and pebbles along the coast. This can be by wave action or the wind
What is a spit
A long narrow ridge of sand or shingle, one end is attached to the land whilst the other extends to sea
What is deposition
When sediment is dropped somewhere else on the coastline
What is a bar?
A ridge of sand or shingle across the entrance of a bay or river mouth. Freshwater is trapped behind it to form a lagoon
What is longshire drift
Longshire drift is the process where material is transported along the coast. It involves the direction of wind, creating waves which approach the coastline at right angles. Due to gravity, sediment is picked up by the backswash and is then transported, in the direction of the wind, and deposited again with the swash, somewhere elsewhere on the coastline. This happens in a zig zag movement.
