Coasts

Question 1

What do waves erode cliffs to form?

Answer 1

wave-cut platforms

Question 2

Where do waves cause the most erosion?

Answer 2

foot of a cliff

Question 3

Explain the process of a wave-cut platform?

Answer 3

• erosion occurs at foot of cliff
• wave cut notch formed and erosion continues
• rocks above notch become unstable and collapse
• collapsed material is washed away and new notch forms
• as the process repeats, cliff retreats

Question 4

Explain the process of headlands and bays?

Answer 4

• form when alternating band of resistant and less resistant rock are along the coast
• less resistant rock (clay) is eroded quickly by water, forming a bay ( gentle slope)
• hard resistant rock is eroded more slowly and is left jutting out, forming a headland ( steep side)- headlands have steep sides

Question 5

Which type of rock has a low resistance to erosion

Answer 5

-soft rock/ rocks with lots of joints

Question 6

Which type of rock has a high resistance to erosion

Answer 6

-hard rocks with solid structure

Question 7

What can headlands be eroded to form?

Answer 7

caves, arches and stacks

Question 8

What are headlands weaknesses that mean they can form caves arches and stacks?

Answer 8

made from resistant rock and have weaknesses like cracks

Question 9

How do

• caves form
• arches form
• stacks form
• stumps form

Answer 9

• waves crash into headlands and enlarge the cracks by hydraulic power and abrasion
• repeated erosion and enlargement of cracks form caves
• continued erosion deepens the cave until it breaks through the headland forming an arch
• erosion continues to wear away the rock supporting the arch, until it collapses forming a stack is formed
• more erosion then weakens the structure of the stack forming a stump

Question 10

What is hydraulic power?

Answer 10

waves crash against rock and compress air in cracks, puts pressure on ricks, repeated compression widens cracks and bits fall off

Question 11

What is abrasion?

Answer 11

eroded particles in the water scrape and rub against rock, removing small pieces

Question 12

What is attrition?

Answer 12

eroded particles in the water smash into each other and break into smaller fragments

Question 13

What is the process that transports material along the coats?

Answer 13

longshore drift

Question 14

What is transportation

Answer 14

-movement of material

Question 15

Explain longshore drift?

Answer 15

• waves follow the direction of prevailing wind
• waves usually hit beach at oblique angle (non right angle)
• swash carries material up the beach in the same direction as waves
• backwash carries material down the beach at right angles, back toward the sea
• overtime material zigzags along coast

Question 16

What are the four processes of transportation?

Answer 16

traction, saltation, suspension, solution,

Question 17

What is traction?

Answer 17

large particles like boulders are pushed along the sea bed by the force of water

Question 18

What is saltation?

Answer 18

pebble- sized particles are bounced along the sea bed by the force of water

Question 19

What is solution?

Answer 19

soluble materials dissolve in the water and are carried along

Question 20

What is suspension?

Answer 20

small particles like silt and clay are carried along in the water