holderness case study Flashcards
holderness key facts
60km flambourough head to spurn head
1m recede a yr (highest europe)
3 miles land lost and 20 villages since roman time
where is holderness
NE england
yorkshire
geology holderness
chalk flamborough head to north bridlington
- cave arch stack stump, wave cut platform
- horizontal bedding planes
boulder clay bridlington to spurn head
-slumping
-sandy beach from cliff erosion
- 1.7m lost per year
- 7m tidle range
spurn point
- 5k long sand spit
-salt marsh and mud flats behind
- hooked
why so much erosion here
500-800Km NE fetch from Norway
warm atlantic ocean current circs N sea adding energy and inc freq destructive waves
depressions and winter storms cause big storm surges and higher sea levels.
more rain aswell so slumping occurs
sea floor very deep
little fricton
little wave energy absorbed
LSD and beaches at holderness
N to S
narrow beaches due to small size of clay so easily removed
destructive waves so little deposition
ocean current meets outflow river humber, flow turbulent, sediment deposited, spurn head formed
sub aerial processes at holderness
mechanical - wet and dry clay
rainwater saturated boulder clay
rotation slump
material removed in suspension
man made processes
groynes
- caused terminal groyne syndrome
£1.9 mill on 2 rock groynes and granite barrier to protect mappleton
- erosion to S (great cowden) has trebled as beach starved and unprotected
impact sea level holderness
slow eustatic rise
inc erosion and flooding
spurn head shrinking
describe flambourough head
chalk resistant and horizontal bedding planes
- wave cut platform
vertical joints lead to cave and geo
wave refraction on headland leads to arch and stack
describe holderness cliffs
boulder clay
rainwater enters and causes slump seawards
- inc by removing vegetation and urbansiation
waves remove slumped material and lsd transports it south (1/2 mill tonnes/yr)
cliffs unprotected
more erosion
describe spurn head
sediment deposited
recurved
salt marsh and sand dune ecosystem behind
what happened at barmston
storm drainage pipe trapped sediment
acted like groyne
led to term groyn syndrome
had to install rock armour
formed bay due to erosion
what happened at ulrome
collapsed roads
forced caravan rollback
no defences
site abandoned
what happened at skipsea
road collapsed into sea
no management
what happened at bewholme atwick
roads into sea
pipes and cables visible
abandoned caravan park
land low economic val
what happened at mappleton
substantial village so defences
lots slumping
boulder groynes
rip rap rock armour (from norway 2mill)
- large beach produced
term groyn synd
- huge crenulated bay
low value land lost
what happened at hornsea
lots coastal management
concrete sea wall which got upgraded to recurved
wooden groynes
riprap to protect sea wall
what happened at aldborough
roads and coastguard station into sea
nothing done