CASE STUDY: high energy coastline (Holderness) Flashcards
Background info
Holderness coastline located in Yorkshire. Extends 61km from Flamborough to Spurn Point
Fact + av. annual rate of erosion
Holderness coastline is one of Europe’s fastest eroding coastlines w annual rate of erosion at approx. 2m/year
How much of Holderness has been lost to erosion since Roman times?
Approx. 3 miles of land has been lost since Roman times including 23 towns/villages
What comes from the North Sea?
Strong destructive wave action
How far has Ringborough Farm been eroded between 1939 and 2010?
Has gone from 145 acres (1939) to 70 acres (2010)
What is the geological make up of the Holderness Coastline (North York Moors + Flamborough Head)?
- North York Moors rise up to 400m above sea level + is comprised mainly of shale/limestone
- Flamborough Head is large chalk headland topped w glacial till left behind from most recent glacial period
What is glacial till?
unsorted material deposited directly by glacial ice
What is the fetch of the dominant waves coming from the north and northwest?
fetch is 1500km+
What was the wave height of the dominant waves coming from the north and northwest?
Wave height was measured to exceed 4m
What are the av. rates of erosion of weak rocks and resistant rocks?
Rates of erosion on av:
- weak rocks (clay/shale), around 0.8m/year
- resistant rocks (limestone/sandstone), less than 0.1m/year
Describe the cliffs at Flamborough Head
Cliffs made of chalk (verystrong), so high + steep (typically 20-30m high), however glacial till has been lowered by mass movement, creating a gradient of roughly 40 degrees
Describe the cliffs at Saltburn
Cliffs are much taller but are ‘stepped’ w a lower gradient, due to varying rock types
How can the variation in rock type be described and how has it created bays and headlands?
Partly discordant coastline
Bays and headlands formed at Saltburn
Weak shales have been eroded to form the bay, whilst resistant sandstone lies either side to form two headlands (Ravenscar and Ness Point)
Bays and headlands formed at Flamborough Head
formed of chalk, w bays of clay either side
What landforms have formed on headlands in Flamborough Head?
at Selwick’s Bay on one side of Flamborough Head, a joint in the chalk has been enlarged. A stack called Green Stack’s Pinnacle have been formed by this process at Flamborough Head. Also, several blowholes are present at Selwick’s Bay.
Why is coastal management needed at Hornsea?
Up to 3m of erosion/year bc cliffs are formed from weak boulder clay. Management protects tourist features such as arcades + hotels + creates a sandy beach
What coastal management strategies have been implemented at Hornsea?
- Sea walls
- Wooden Groynes repaired + built at a cost of £5.2m
What are the negative consequences of the coastal management strategies at Hornsea?
- Tourism leads to congestion in summer, negatively impacting on locals
- The wall is unattractive
Why is coastal management needed at Mappleton? (Damages)
- There was £2.9 million of damage a year before the management was put in place.
- Sandy beach is protected +
- also protects the town and the B1242 motorway
What coastal management strategies have been implemented at Mappleton?
Rock armour at a cost of £2 million
Why is coastal management needed at Eastington?
There is a Gas Terminal at Eastington + 2.25% of all UK gas comes from this station
What coastal management strategies have been implemented at Eastington?
Rock armour at a cost of £4.5 million
What are the negative consequences of the coastal management strategies implemented at Eastington?
- Rock armour protects the gas from erosion, but not the village
- Rock armour is preventing material reaching Sites of Specific Scientific Interest (SSSI) further South, such as sand dunes
