Coasts CS (holderness) Flashcards
where is the Holderness coastline
Flamborough head to spurn head
how long is the H coastline?
61km long
what erosion occurs at holderness?
cliffs made of till (boulder clay) coast exposed to destructive waves from N sea during storms. e.g (great Bowden, rate of erosion 10m year)
what are the 4 main coastal processes?
- erosion
- mass movement
- transportation
- deposition
what mass movement occurs at the Holderness coast?
-clay prone to slumping when wet, water makes clay heavier and slippy= unstable
what transportation happens at the H coast?
-prevailing wind transport material S. these winds create an ocean current, transports material by longshore drift
what deposition occurs at the coastline?
ocean current meets the outflow of humber river, flow becomes turbulent & sediment Is deposited
what types of landscapes are around the N/S of holderness?
- N-steep chalk cliffs, wave cut platforms, sandy beaches
- S- less steep boulder clay cliffs, depositional feature
what are headlands characteristics like at holderness? name of headland?
- N of area, boulder clay overlies chalk (chalk= hard, less easily eroded has formed headland)
- Flamborough head, stacks, caves, arches
where are the sand dunes along holderness? how are they created?
spurn head, material transported by wind is deposited= sand dunes
where are the slumps along holderness? what occurred?
-Atwick sand, 7 occurred and have not been eroded
how and where have beaches formed?
- S of flamborough sheltered form wind and waves and a wide sand and pebble beach has formed
- near bridlington
how and where have spits occurred?
erosion/ longshore drift = spit with a recurved end across the mouth of Humbry Estuary (spurn head)
what is one of the biggest problems that has occurred at holderness?
-retreated 4km over past 2000yrs, lost 30 villages
what are the 3 consequence of erosion?
- loss settlements e.g. skipsea and 80,000m^2 of good quality farmland lost
- loss of infrastructure- gas terminal at eastington 25m for cliff edge
- loss of sites of special scientific internet e.g. lagoons
how much of the H coastline is protected by hard engineering?
11.4km of 61km
what is bridlington protected by?
4.7km sea wall
timber groynes
what is Hornsea protected by?
sea wall
timber groynes
riprap that protect village
what is Mappleton protected by?
1991= 2 rock groynes & 500m long revetments. cost £2 million built to protect village & B1242 coastal road
what is skipsea protected by?
a land owner used gabions to protect caravan park
what is withernsea protected by?
groynes
sea wall
riprap in front of wall after damaged in storm 1992
what is eastington gas terminal protected by?
revetments
what is E side of spurn head protected by?
groynes
riprap
why are groynes unsustainable?
groynes trap sediment, ^ width of beaches protect local area but ^ erosion of cliffs down drift e.g. mappleton
why is reduced sediment bad for sustainability?
reduction of sediment ^ risk of flooding along Humber, but ^ erosion along Lincolnshire coast
why are bays unsustainable?
wave pressure on headlands ^ and eventually cost of maintaining sea defences= too high
what is the SMP for Holderness over the next 50yrs?
-“hold the line” (brid, withersea, Hornsea, mappleton, EGT),
“do nothing” along less pop areas
what are management plans for caravan parks?
managed realignment (compensation??)
what happened in 1995 after a SMP?
“do nothing” technique= saves money and spit naturally, but overfishing damage to marsh environment
what is an issue at EGT?
700 people not protected=^ erosion
