2.3 Coasts

Question 1

How is a sand spit formed?

Answer 1

(Prevailing) wind approaches from an angle ;
Swash comes in at an angle/obliquely;
Backwash is vertical/straight out to sea;
Material is moved in zigzag manner;
(Known as) longshore drift;
Spit develops where there is a change in direction of coastline;
Recurved/hook by waves from other directions, etc.

Question 2

Describe the processes of coastal erosion

Answer 2

Hydraulic action;
Air compressed in crack in rocks by power of waves;

Corrosion/solution;
Rocks like limestone dissolved by acids in sea water;

Corrasion/abrasion;
Waves pick up loose materials and use them to grind the cliffs;

Attrition;
Materials reduced in size as they hit each other when being carried or moved around by waves, etc.

Question 3

What are waves caused by?

Answer 3

The wind drags the surface of the water

Question 4

Definition of swash

Answer 4

The flow of water rushing up the beach when a wave breaks

Question 5

Definition of backwash

Answer 5

the flow of water back to the sea after a wave breaks

Question 6

Features of constructive waves

Answer 6

Carries out deposition
Wide, gently sloping waves
Less powerful waves
Breaks on the shore
Transports material

Question 7

Features of destructive waves

Answer 7

Carries out erosion
Storm conditions
Lots of wave energy
Long fetch
Water plunges forwards
Steep beach gradient 
High wave height

Question 8

Definition of longshore drift

Answer 8

waves carry material along the coastline

Question 9

Problems which coastal erosion may cause for people in the area

Answer 9

• damage of housing
• loss of farmland
• negative impact on tourism
• roads destroyed
• high cost of protection methods

Question 10

Definition of headland and bays

Answer 10

Alternate layers of hard and soft rock

Question 11

How are caves formed?

Answer 11

• hydraulic action
• causes cracks in the cliff to widen
• erosion continues, forming a cave

Question 12

How are stacks and stumps formed?

Answer 12

• Erosion continues until the roof of the cliff collapses
• Too heavy to withhold
• Separated land = stack
• Weathering erodes the top = stump

Question 13

How are sand dunes formed?

Answer 13

Sand blown by wind;
Obstruction/pebble/litter/plant blocks wind;
Causes velocity of wind to reduce/eddies;
Deposition;
Colonization by more plants;
Gets larger over time;

Question 14

Hazards of coasts

Answer 14

Flooding
- Death
- Cost of flood defense
- Destruction of farmland
 - Unemployment
- Destruction of buildings
- Lack of water and food supply
- Schools and hospitals destroyed
Tropical storms
Erosion of land
- Loss of land
- Collapsed housing

Question 15

Opportunities of living near a coast

Answer 15

• trading
• transportation
• tourism –> more job opportunities
• fertile soil –> farming
• renewable energy
• Abundant supply of water
• Leisure
• Diverse eco-system habitats

Question 16

How are wave-cut platforms formed?

Answer 16

• Formed by weathering and erosion along the coast

Question 17

How are beaches formed?

Answer 17

• Composed of shingle and sand
• Sand is deposited by constructive waves (calm water)
• Shingle is deposited by destructive waves (rough water) further into the bay

Question 18

How are headlands and bays formed?

Answer 18

• In the beginning, the hard and soft rock are at the same level
• As the soft rocks erode faster, the layers of hard rock. are left jutting out. These are called headlands.
• The area where the soft rock has eroded is called the. bay

Question 19

How are headlands and bays formed?

Answer 19

• In the beginning, the hard and soft rock are at the same level
• As the soft rocks erode faster, the layers of hard rock are left jutting out. These are called headlands.
• The area where the soft rock has eroded is called the bay

Question 20

How are cliffs formed?

Answer 20

• Weathering and erosion

- The soft rock is eroded away by destructive waves and solution –> hard rock left forms a cliff