The Coastal Zone Flashcards
Name the 4 types of EROSION.
- Hydraulic action - Waves hitting against the rock face with high impact.
- Abrasion - When waves throw pebbles and sand against the rock face.
- Attrition - When rocks in the waves collide with each other, splitting into tiny particles.
- Solution - When chemical reactions cause some rocks (e.g: Limestone) to dissolve in solution, causing the pH level to increase.
Name the 4 types of TRANSPORT.
Name the 2 types of Mass Movement.
Name the 3 types of Weathering.
How is a Spit formed? Show in labelled diagrams.
Describe with a diagram how Longshore Drift occurs.
What are the properties of Constructive and Destructive waves?
What is the difference between Swash and Backwash?
- Swash is the forward flow of a wave out the sea.
- Backwash is the return flow of a wave back towards the sea.
What 5 factors influence waves?
- Wind strength.
- Wind direction.
- Wind duration.
- Fetch.
- Seabed structure.
Describe with diagrams how Headlands and Bays are formed.
Describe with diagrams how Wavecut Platforms are formed.
What is the cause of Caves, arches, stacks and stumps?
A line of weakness that is attacked by hydraulic action and abrasion.
Describe with diagrams how Caves, arches, stacks and stumps form.
What is a beach?
The area of land formed by the materials deposited by the sea.
Why do some beaches have sand and some have pebbles?
It depends on how resistant the rocks on that beach are:
- Less resistant rocks can be eroded easier into smaller pieces (Sand).
- More resistant rocks are more difficult to erode, so are in larger pieces (Pebbles).
Draw a diagram, write an explanation, explain the Advantages and Disadvantages of a Sea Wall and choose whether it is Hard or Soft management.
A Sea Wall is hard management.
Description: Slows down erosion by acting as a strong wall that’s very resistant.
Advantages:
- Protects cliff.
- Slows erosion.
- Long life span - 75 years.
- Prevents coastal flooding.
Disadvantages:
- Expensive to build - £10k sq.m.
- Expensive to maintain.
- Long time to build.
- Erosion can get behind by digging underneath.
- Eyesore.
Draw a diagram, write an explanation, explain the Advantages and Disadvantages of Beach Revetment and choose whether it is Hard or Soft management.
Beach Revetment is hard management.
Description: Use of wood or concrete that is sloped and laid along the coast. Energy from waves is absorbed.
Advantages:
- Cheaper than sea walls
- Allows more build-up of sediment on the beach.
- Less-unsightly than sea walls.
Disadvantages:
- Still expensive - £2000 sq/m (Depends on material).
- Eyesore.
- Liable to rapid damage.
- Not cheap to replace.
Draw a diagram, write an explanation, explain the Advantages and Disadvantages of Gabions and choose whether they are Hard or Soft management.
Gabions are hard management.
Description: Cage filled with rocks.
Advantages:
- Cheap - £11 sq/m.
- Life span of 20-25 years.
- Easy+Quick to install.
- Help drainage.
- Prevents LSD. Keep beach.
Disadvantages:
- Eyesore until covered-over.
- Can cause problems elsewhere due to LSD prevention.
Draw a diagram, write an explanation, explain the Advantages and Disadvantages of Groynes and choose whether they are Hard or Soft management.
Groynes are hard management.
Description: Wooden fences or bolders 200m apart. Built at a right angle. Very low walls.
Advantages:
- Prevents LSD. Keep beach.
- Long lifespan, 25 years.
- Reduces erosion.
Disadvantages:
- Expensive - £2,000 sq/m.
- Looks unnatural.
- Can cause massive drops in beach.
- Can cause problems elsewhere due to LSD prevention.
Draw a diagram, write an explanation, explain the Advantages and Disadvantages of Rip-rap and choose whether it is Hard or Soft management.
Rip-rap is hard management.
Description: Large interlocking man-made boulders which protect the coast by breaking up the waves. Made from concrete or rock. It is on-shore.
Advantages:
- Absorb energy of waves.
- Encourage build-up of beach material.
Disadvantages:
- Expensive - £3,500 sq/m.
- Boulders can be difficult to transport.
- Eyesore.
- Strong waves can move or undermine the boulders.
Draw a diagram, write an explanation, explain the Advantages and Disadvantages of Beach Rebuilding/Beach Nourishment and choose whether it is Hard or Soft management.
Beach Rebuilding/Beach Nourishment is soft management.
Description: Replaces a beach that has been removed by LSD. Involves using a ship and throwing sand from the seabed onto the beach.
Advantages:
- Attracts tourists.
- Cheap, £20 sq/m.
- Natural defence against erosion.
- Replaces material lost by erosion each year.
Disadvantages:
- Expensive if transported by other means.
- Requires constant maintenance.
Draw a diagram, write an explanation, explain the Advantages and Disadvantages of Off shore breakwater and choose whether it is Hard or Soft management.
Off shore breakwater is hard management.
Description: Dumping concrete interlocking materials into the sea (or boulders).
Advantages:
- Very strong.
- Less impact on other areas of the coastline.
Disadvantages:
- Expensive - £3,500 sq/m.
- Eyesore.
- Does not directly prevent beach material from being eroded.
Draw a diagram, write an explanation, explain the Advantages and Disadvantages of Controlled retreat and choose whether it is Hard or Soft management.
Controlled retreat is soft management.
Description: Allowing land to flood.
Advantages:
- Land becomes marsh, slowing waves and reducing erosion.
- Creates new habitats.
- Cheap.
- Already in place.
Disadvantages:
- Land is lost.
- Land will be flooded.
- No agreed protocols on monitoring.
Describe with a diagram a saltmarsh.
