Coastal Landscapes

Question 1

Weathering

Answer 1

The break-down of rock in-situ
* Mechanical weathering physically breaks up rock
* Freeze-thaw or frost shattering
* chemical weathering with slightly acidic rain water
* biological weathering when trees grown in cracks of rocks

Question 2

Erosion

Answer 2

• hydraulic action when waves hit cliffs
• attrition when rocks hit each other and become smoother
• abrasion is when waves pick up material and move it along

Question 3

Transportation

Answer 3

• traction when heavy particles are dragged along seabed
• saltation when small materials bounce along sea floor
• suspension when fine material are held in water
• solution when dissolved in liquid

Question 4

Longshore drift

Answer 4

• It is the main process of deposition and transportation along the coast
• Waves approach the beach at an angle due to the prevailing wind
• As the waves break, the swash carries material up the beach at the same angle
• As the swash dies away, the backwash carries the material down the beach at right angles (90°)
• The process repeats, transporting material along the beach in a zig-zag movement

Question 5

Erosional Landforms

Answer 5

Cliffs and wave-cut platforms
* As the sea attacks the base of a cliff between the high and low water mark, a wave-cut notch is formed
* Abrasion, corrosion and hydraulic action further extend the notch back into the cliff
* The undercutting of the cliff leads to instability and collapse of the cliff
* The backwash of the waves, carries away the eroded material, leaving behind a wave-cut platform
Caves, arches, and stacks
* large cracked opened by hydraulic action which then grows bigger due to abrasion until cave breaks through headland and arch erodes and colllapses leaving tall rock stump. This then erodes to form stump.
SPIT
is formed from longdhore drift and deposition
BARS
when spit grows across bay

Question 6

Hard engineering methods

Answer 6

Sea Wall
A wall, usually concrete, and curved outwards to reflect the power of the waves back out to sea
Groynes
Wood, rock or steel piling built at right angles to the shore, which traps beach material being moved by longshore drift
Gabions
A wall of wire cages filled with stone, concrete, sand etc built at the foot of cliffs absorbing wave energy

Question 7

Soft Engineering

Answer 7

Beach replenishment
Pumping or dumping sand and shingle back onto a beach to replace eroded material
Dune regeneration
Planting vegetation helps to create or stabilise sand dunes and beaches
Reduces wind erosion