Coasts (Mock 1) Flashcards
(39 cards)
What is dip?
- Tectonic feature
- Angle of inclination of rock strata
- Sedimentary rocks are deposited
- Tilted by tectonic forces
What is the case study for horizontal dip?
Glamorgan Heritage Coastline - Carboniferous Limestone
What angle is the strata on high angle seaward dips?
45°
What angle is the cliff face on a low angle seaward dip?
Over 90°
Where has experienced mass movement via rotational slumping
Christchurch Bay - Barton on Sea
Where has experienced mass movement due to rockfall?
The Jurassic Coastline - South Dorset in April 2020
Where has a discordant coastline
Bantry Bay, SW Ireland
What is the strata at Bantry Bay
RS: Devonian Old Red Sandstone
WS: Carboniferous Limestone
Where has a concordant coastline?
Lulworth Cove, South Dorset Coastline
What is the strata at Lulworth Cove?
RS: Portland Limestone
WS: Wealden Clay
What is the sediment cell in?
Dynamic equilibrium
Example of negative feedback loops
Wave cut notch -> blockfall -> natural rock armour -> blockfall less likely as cliff protected
Example of positive feedback loops
High winds remove plants from sand dunes -> no roots -> soil less stable and leaves don’t reduce wind -> Increased recession rates -> more sediment in the cell
Name a plant that grows in sand dunes?
Marram Grass
Name three policy options for coastal management
- Do nothing
- Managed realignment
- Hold the line
What is hard engineering?
Man made invasive structures that reduce flood risk
What is soft engineering?
Works with nature to protect the coastline
How long is the sea wall at Hornsea & Bridlington?
4.7 km
Where has a sea wall?
Hornsea & Bridlington
Where has groynes?
Holderness coastline -> Hornsea
How much do groynes cost?
£150 for every 2.5 km
How much does beach nourishment cost?
£2 million for every km
Where has experienced mangrove replanting?
Bangladesh - Sundarban
How much of Bangladesh has experienced mangrove replanting?
450 hectares
