Coasts - Processes

Question 1

What are the 4 main inputs into a coastal system?

Answer 1

1. Wind:
   - Many coasts have a prevailing wind direction (wind in the UK comes West-East from Atlantic and effects direction waves hit a coast, and when wind speeds are higher waves will have more energy (bigger = more erosion)
   - Fetch is the distance of open water wind blows and helps determine the size of wave (bigger fetch = bigger wave)
2. Waves:
   - Constructive waves = strong wash weak back swash and helps form beaches through berms (ridges), deposits sediment
   - Destructive waves = weak swash strong back swash and transports sediment
   - Wave refraction = high energy waves hit a headland, lower energy part of wave spills in bay
3. Current
   - Rip currents = strong currents moving away from shoreline (dangerous)
   - Upwelling = cold water from deep in ocean travels to surface
4. Tides:
   - Spring tide are high tides twice a month
   - Neap tides low tides

Question 2

What are the 2 types of coast?

Answer 2

• Low energy coast = wave energy low, deposition rates higher than erosion rates, include spits and beaches
• High energy coasts = strong prevailing winds + high energy waves, erosion higher than deposition (Cornish Coast)

Question 3

What are sediment cells?

Answer 3

distinct areas of coastline separated by boundaries e.g. Holderness Coast from Spurn Point to Flambourough Head 61km long.

Question 4

What are the 4 coastal processes?

Answer 4

Weathering, mass movement, transportation, erosion.

Question 5

What are the types of erosion?

Answer 5

Hydraulic action = force of wave erodes rock
Abrasion = load in wave colliding with cliff
Attrition = load in wave erode down into smaller pieces
Solution = acidic water dissolves small rock

Question 6

What are the types of transportation?

Answer 6

• Traction = large stones rolling along seabed
• Saltation = small stones bounce along seabed
• Suspension = small particles carried in the moving water
• Solution = dissolved materials in water

Question 7

What are the 3 types of weathering?

Answer 7

• Physical weathering/ freeze thaw
• Biological Weathering = animals burrowing in cracks or algae growing
• Chemical weathering = acidic rain falls into cracks breaking down rock

Question 8

What are the 4 types of mass movement?

Answer 8

• Landslides = softer rock cliffs slip downhill
• Rock Fall
• Mudflow = saturated soil flows downhill
• Slumping = soil becomes heavy from rain and slumps under weight