coastal landscape and change Flashcards
(21 cards)
Littoral zone order
Backshore
Foreshore
Nearshore
Offshore
Backshore
above influence of waves
.storm beaches
.cliff
Foreshore
inter tidal zone
.ripples
.beach cusps
.berms
Nearshore
where waves break
.runnels
.ridges
Offshore
beyond breaking waves
.offshore bar
factors effecting coastal landscapes
.human->pollution, buildings
.marine factors->waves, winds, tides, currents
.climate->winds, weather, climate change, glaciation
.geology
.tectonics->coastal uplift, volcanic activity
.biotic factors
Sub aerial-> temperature, weather
Classifying rocky cliffed coasts
.Physical->cliffs few to hundreds meters high
.energy->destructive waves, long fetch, more erosion
.primary->dominated by land processes
.Emergent->coasts rising
.tidal range->micro 0-2m, meso 2-4m
.landforms-> erosional eg cliffs, wave cut platforms
Example: Atlantic coasts of Norway
classifying coastal plains
.low energy-> short fetch, higher deposition rates, sheltered
.secondary processes-> more marine processes
.submergent-> sea level rising
.tidal range-> macro(>4m)
.landforms-> depositional eg beaches, spits
Example: Mediterranean Sea coasts
Sedimentary rocks
.formed from layers of sediment on sea/lake beds over millions of yrs
Igneous rocks
Formed when magma is pushed out earths crust through volcanoes
Metamorphic rocks
Formed by recrystallisation of sedimentary and igneous through heat and pressure
Have crystalline structure often in foliation
Uk geology
.tees-exe line -> north east to south west
.below line are low energy coasts with short fetch because it’s made of sedimentary
.above are high energy coasts with long fetch and metamorphic/igneous rock
Example: Cornwall
Coastal system
Inputs, processes, outputs
And energy needed to function
Inputs:
.marine-> waves, tides
.atmospheric-> weather/climate
.land-> rock type + structure
.people-> human activity
Processes:
.weathering
.mass movement
.erosion
.transport
.deposition
Output:
.erosional landforms
.depositional landforms
Energy:
.solar
.gravity
Dynamic equilibrium
What upsets it
Negative/positive feedback
.balances state of coastal system over time
.storms, global warming, human intervention
.negative-> restores equilibrium by self regulation
Positive-> changes in system amplified
Example: east coast isle of purbeck
.discordant coast
.more resistant chalk, less resistant Weldon clay + bagshot sands(swanage bay),more resistant limestone(durlston head)
.swanage bay-> low energy coast, low gradient
.Durlston head-> steep vertical cliffs
Example: lulworth cove
.post glacial river at end of last ice age carved valley
.rising sea level flooded it
.marine processes broke through harder limestone
.softer Weldon clay exposed to erosion
.cove widens
.more resistant chalk reached so erosion slows
Example: Dalmatian coasts, Adriatic Sea
.concordant coast
.in Alpine Orogeny tectonic forces produced by collision of plates compressing limestone
.created anticlines and synclines parallel to coast
.sea levels rose at end of Devensian and synclines flooded
Example: haff coasts
.last ice age sea level was 100m lower than today
.meltwater rivers deposited sand + gravels in outwash plains Baltic Basin
.sea level rose constrictive waves pushed s+g onshore
.creating long bar with lagoon behind
Def of :
.strata
.bedding planes
.joints
.folds
.faults
.dip
Example:holderness coastal recession
Vegetation
