UK Evolving physical landscape - 4A - Coastal change

Question 1

Give an example of a hard rock

Answer 1

Granite

Question 2

Give an example of a soft rock

Answer 2

clay

Question 3

Why do harder rocks erode slower?

Answer 3

More resistant = erode slower

Question 4

What is a joint?

Answer 4

small cracks found in a rock

Question 5

What is A fault?

Answer 5

Larger cracks found in a rock

Question 6

What is a concordant coastline?

Answer 6

Rock parallel to coast

Question 7

What are discordant coastlines?

Answer 7

Perpendicular to coast
Headlands and bays formed

Question 8

What are the 2 different types of wave

Answer 8

Constructive
Destructive

Question 9

Features of a constructive wave?

Answer 9

Strong swash
weak backwash
deposits sediment

Question 10

Features of a destructive wave?

Answer 10

Strong backwash
weak wash
Erodes sediment

Question 11

Describe Longshore drift

Answer 11

Longshore drift transports sediment along coastlines
Waves break at an angle to the coast
Sediment pushed up the beach by swash
Dragged back down at right angles by backwash

Question 12

How are bays formed?

Answer 12

Soft, less resistant rock is eroded faster

Question 13

How are heads formed?

Answer 13

Harder, resistant rock is eroded slower

Question 14

what are the 4 steps needed to create wave-cut platforms?

Answer 14

1. Sea attacks base of cliff (abrasion and hydraulic action) creates a wave-cut notch
2. Wave-cut notch becomes larger = cliff collapses
3. Cliff retreat
4. Wave-cut platform formed

Question 15

How are caves, arches, stacks and stumps formed?

Answer 15

1. caves enlarged by hydraulic action
2. Arch formed by destructive waves
3. Stack = arch eroded and collapses -> stack results
4. Stump = Stack eroded by abraision -> stack collapses

Question 16

How are caves, arches, stacks and stumps formed?

Answer 16

1. caves enlarged by hydraulic action
2. Arch formed by destructive waves
3. Stack = arch eroded and collapses -> stack results
4. Stump = Stack eroded by abrasion -> stack collapses

Question 17

How does a wave form?

Answer 17

Waves are created by winds as they blow over the sea

Shallow water near the coast causes friction with the seabed

The top of the water is travelling faster so it starts to tip forward

The wave then topples forward or breaks

Question 18

How do spits form

Answer 18

Spits are formed due to deposition

Longshore drift occurs along the coastline but as the wave lose energy the deposit the sediment

Normally due to going into a sheltered area such as behind the headland or a mouth/estuary

The deposit of sediment overtime this creates a spit

Question 19

How do bar and lagoons form?

Answer 19

• continuation of a spit formation
  -Spit grows and joins 2 headlands
• lagoon forms
• area becomes infilled by deposition

Question 20

What are sea walls

Answer 20

Concrete walls placed at the foot of the cliff to prevent erosion. They are curved so they reflect the energy back into the sea

Question 21

What is rock armour

Answer 21

Large boulders placed at the foor of the cliff. They break the waves and absorb their energy

Question 22

What are gabions

Answer 22

Rocks which are held in mesh cages and placed in area affected by erosion

Question 23

What are groynes

Answer 23

Wooden or rock structures built at right angles into the sea

Question 24

What is beach replenishment

Answer 24

Sand and shingle from the sea bed is moved towards the beach

Question 25

What is beach reprofiling

Answer 25

Reshaping the beach using existing beach material

Question 26

What is dune regeneration

Answer 26

Grass planted in sand dunes to stabilise the dunes and helps to trap sand to build them up

Question 27

What is dune fencing

Answer 27

Fences are built on the sandy beaches, which encourage new dunes to form

Question 28

Advantages and disadvantages of sea walls

Answer 28

Very effective Very long lasting Very expensive £2000 per metre Very ugly

Question 29

Advantage and disadvantage of groynes

Answer 29

Not to expensive Builds up beaches Starves the beack further down the coast line of sediment

Question 30

Advantage and disadvantage of gabions

Answer 30

Cheap and easy to mantain £100 per metre Absorbs wave energy Not very strong Looks unatural

Question 31

Advantages and disadvantages of rock armour

Answer 31

Relatively easy to maintain Effective at reducing wave energy Can beshifted if the rock is too small Expensive to transport

Question 32

Advantages and disadvantages of beach nourishment

Answer 32

Blends in with the existing beach Creates wider beaches Can kill or destroy animal habitats Expensive and has to be repeated

Question 33

What are the advantages and disadvantages of beach reprofiling

Answer 33

Provides an effective buffer for the coastline Looks reasonably natural Can be expensive Has to be done regularly

Question 34

What are the advantages and disadvantages of dune regeneration

Answer 34

Wave energy is absorbed It is cheap The protection is limited to a small area Can be damaged by storms or waves

Question 35

What are the advantages and disadvantages of dune fencing

Answer 35

Constructed out of natural material Have minimal minimal impact on natural systems Can be damaged by storms Needs maintenance