1. Coastal Environments

2. Mechanical Weathering
Rock crystals expand and contract very common as sea has high salt content
Water expands 9% when it freezes to form ice less common as sea keeps coast mild
As crystals grow they exert pressure
Weight is taken off the rock
Surface layer flakes off
Expands when wet and contracts when dry, very common in inter tidal areas
Jointed rock
Freeze thaw
Salt Crystal growth
Exfoliation
Wet/dry
Granular disintegration
Block disintegration
Pressure release
Match the starter with the correct ending

3. Which mechanical processes are shown in the photographs?
                                                            

4. Chemical weathering
Oxidation - speeds up in moist coastal areas
Carbonation - limestones dissolve in carbonic acid
Hydrolysis - this affects rocks with feldspar minerals
Hydration - when minerals absorb water, expand and change
Solution - some rocks dissolve in water
Acids - acid rain from pollution ( coastal power stations)

5. Which chemical processes are shown in the photographs?

6. Biological weathering

7. Mass Movement
Remember….. The processes that shape a river environment are also affected by slope processes as well as weathering processes.
Mass movement is…. The movement of material under the force of gravity. It tends to reduce the slope angle,
It is classified on speed and water content
Slow ~ soil creep and rain splash
Fast ~ flows (wet), slides and slumps (dry)
Very fast~ falls, avalanches

8. Factors which control type and rate of movement~
Climate
Rock type
Rock structure
Relief
Vegetation
Rates of weathering
Aspect
Shock from something to trigger it eg storm
Human activity

9. Wave terminology

10. Constructive waves

11. Destructive waves

12. Wave factors
Waves control ENERGY and MOVEMENT
Wave shape
Wave size
Fetch
Roughness
Depth and gradient
Load
Tides
Storm surges

13. EROSION
Abrasion~load wearing away cliff
Hydraulic action~ sheer force and weight of falling water; especially in cracks ( air pressure)
Attrition~ load collides and grinds away (results in sand)
Solution~ removal of chemical ions
Factors controlling rate of erosion ~ marine factors and coastal factors p15 revision book

14. Remember to link landform description to processes
Landforms of erosion
Remember there are large scale and small scale landforms and you have studied these using named areas.
video
video 2
Remember to link landform description to processes

15. Blowholes and cliff slumping
video

16. Transportation processes~ Traction~ rolled along the bed
Saltation~ bouncing along the bed
Solution~ dissolved in the water
Suspension~ held in the water
Flotation ~ on the surface
Gatm – lsd video
4th one down
Tester – GATM Bond
20th down
Deposition
Rate of deposition is determined by energy loss and the weight of the load. A shallow gradient, wider beach, calmer climate and meeting a river are examples.
Marine deposits include:-
Bed load, Suspension, Solution

17. Depositional Landforms
Video – spit formation
Remember for depostion to take place the following factors are important:~
Plentiful supply of sediment
Longshore drift to transport sediment
An indented coastline – coastline changes direction
Energy levels drop –slow down for example at a river mouth
Bioconstruction – plants to help stabilize the sediment

18. Tombolo
Video - tombolo

19. Coastal Protection
Physical reasons for protection:~
Climate – global warming
Relief – low-lying areas
Aspect – open to large wave fetch
Depth of water
Drainage – deltas – flooding threats
Vegetation
Ecosystem
Geology

20. Human reasons for coastal protection:~
Settlement – Tenby – lots of expensive properties
Source of raw materials – Hallsands – sands and gravels
Industrial needs –
Transport – Mappleton on the Holderness coast
Ports
Fishing
Military ranges – MOD in Castlemartin Pembrokeshire
Tourism & Recreation – Tenby Pembrokeshire
Cultural and historic sites
Coastal management and defence - gatm
Case studies:- Tenby, Holderness,
Hallsands, Abbotts Hall Farm,

21. Identify the scheme describe how it works
Hard Engineering Protection Schemes
Groynes and beach renourishment – gatm
Identify the scheme describe how it works

22. Soft Engineering Protection Schemes
Which shows:~
Replenishment
Beach re-profiling
Fencing – to trap blown sand
Planting vegetation – like marram

23. Land allowed to flood and forms salt marshes that absorb wave energy
Land allowed to flood and forms salt marshes that absorb wave energy. Managed retreat is cheap and natural but needs and area with little or no population.
Managed Retreat