Coasts Flashcards
(18 cards)
1
Q
Hydraulic action
A
waves pound the shoreline, enter cracks, compress air, cracks expand
2
Q
Abrasion
A
- rocks hurled at the base of the cliff
3
Q
Attrition
A
- rocks crashing together
4
Q
What are the two types of weathering?
A
- mechanical (freeze thaw)
- chemical (acid rain)
5
Q
What are the four types of mass movement?
A
- rockfall
- landslide
-mudflow - rotational slip / slumping
6
Q
Rockfall
A
rocks break away from the cliff face
7
Q
Landslide
A
rocks slide downhill
8
Q
Rotational slip
A
slump of soil and rock along a curve
9
Q
How are wave cut platforms formed?
A
- hydraulic action and abrasion hit the face creating a wave-cut notch
- rock wears creating a overhang
- collapses
- cliff recedes
10
Q
How is material transported?
A
- traction
- saltation (bounce small)
- suspension (fine)
- solution
11
Q
How does a spit form?
A
- swash angle up beach
- change in shape of coast
- spit forms into sea
- wind changes = spit curves
- formation of a salt marsh
12
Q
How does a bar form?
A
- LSD transports material along coast
- deposited
- across a bay between two headlands
- bar connects the headlands
- leaves a lagoon
13
Q
How are sand dunes formed?
A
- blown sand (suspension, saltation)
- form a ridge meets a obstacle
- stabilised by marram grass
- rotting vegetation = fertile
- slack due to wind reducing in size
14
Q
Examples of hard engineering
A
- groynes (LSD, expensive)
- sea wall (deflect energy, expensive )
- rock armour (absorb power, cheap)
- gabions ( absorb energy, cheap)
15
Q
Examples of soft engineering
A
- beach nourishment (depositing sand)
- beach reprofiling (move sand)
- dune regeneration
16
Q
What are the positives and negatives of beach nourishment?
A
- increase tourism
- protects properties
- constant process (expensive)
17
Q
What are the positives and negatives of beach reprofiling?
A
- encourages natural sand dune recovery
- reduces erosion
- not long term solution (expensive)
18
Q
What the positives and negatives of dune regeneration?
A
- natural
- maintains diversity
- easily damaged be storm and people
