Coasts And Coastal Processes

Front 1

• What is a coastline?
  
• How are features made?
• What are coastlines used for?

Back 1

• Where the sea meets the land
  
• Erosion and deposition
• Used for working, living and leisure

Front 2

What are the four types of erosion?

Back 2

• Corrosion - Salt and chemicals dissolve the rocks slowly
• Corrasion - Waves throw sand and pebbles at the rock
• Attrition - Rocks and pebbles collide with each other and grind down
• Hydraulic Action - The weight and force of the waves force air into cracks in the rock and crack it apart

Front 3

How does slumping happen?

Back 3

• Cliffs become saturated with water
• The cliff becomes too heavy to support itself, and a section slides to the ground

Front 4

What are the four processes of transportation?

Back 4

• Traction - Large boulders are rolled along the sea bed
• Saltation - Smaller rocks bounce along the sea bed
• Suspension - Small particles carried along in water flow
• Solution - Dissolved particles carried in waves

Front 5

Describe the process of longshore drift

Back 5

• Waves approach the coast at an angle due to the prevailing wind
• They move sand and shingle with them
• The waves return at 90 degrees, so they drag the material with them
• This repeats, so the material is moved along the coast
• This can be stopped by groynes

Front 6

• What is a constructive wave?
  
• What is a destructive wave?

Back 6

• A constructive wave has a stronger swash and deposits/builds the beach
• A destructive wave has a stronger backwash and takes sediment away

Front 7

Describe the process of cliff retreat

Back 7

• Waves erode the bottom of the cliff and form a wave-cut notch
• This continues until the weight of the cliff cannot be supported
• The flat bit of rock left under the overhang is called a wave-cut platform
• This repeats, and causes cliff retreat

Front 8

How is a headland formed?

Back 8

When hard rock is eroded slower than soft rock

Front 9

Describe how a stump forms

Back 9

• A crack in the headland is attacked and eroded by waves
• This forms a cave
• This cave is eroded, and if it breaks through the headland then an arch is formed
• The arch gets too wide to support the top, so it collapses
• The stack is eroded at the base, and falls to leave a stump

Front 10

What is a beach?

Back 10

A beach is material deposited by constructive waves. It is not permanent

Front 11

How is a spit formed? Give an example of one

Back 11

• Longshore drift transports sediment along the coastline, and the coastline changes direction
• LSD continues in the same direction
• The spit grows in the direction of the prevailing wind
• One end attached to the land, one to sea
• A salt marsh is formed behind
• Permanent features, e.g. Spurn Head

Front 12

• What is a bar?
  
• What is a tombolo?

Back 12

• A bar is when a spit extends all the way across a bay
• A tombolo is a bridge between the mainland and an island. LSD happens from both sides as the island refracts the waves.

Front 13

Give five examples of hard engineering and what they do

Back 13

• Groynes - Trap sediment and stop LSD
• Sea walls - Impermeable, concrete walls. Very effective, but expensive and ugly
• Rip-Rap - Absorb impact of the waves and prevent erosion
• Gabions - Small rocks in cages. Aren't washed away, stop erosion by absorbing impact
• Revetments - Wooden slats with sediment behind, absorb energy. Must be maintained

Front 14

Give two examples of soft engineering

Back 14

• Beach Nourishment - Material is manually replaced. Maintains beach, protects land, not ugly but frequent management needed
• Managed retreat - Allow a piece of coast to be eroded as it is not worth protecting

Front 15

What is I.C.Z.M?

Back 15

Integrated Coastal Zone Management - All of the areas that would be affected in an area reach an agreement on which defenses to put in place

Front 16

Give information about the Holderness coast

Back 16

• Made of very soft rock
• Very fast erosion, 7-10m p/a
• Mappleton - Small village with an important road in. Sea defenses put in place at £2 million
• Areas south of Mappleton eroded much faster due to lack of sediment brought by LSD
• Farms demolished, lost 80m in 2 years