paper 2 Flashcards
What are the social impacts of river flooding?
- death/ injury
- damage to infrastructure
- floodwater contaminated with sewage= lack of clean drinking water
- damaged possessions/ are washed away
- homelessness
- businesses shut down = loss of livelihoods
What are the three main rock types?
- igneous
- sedimentary
- metamorphic
How do rock types vary?
How they are formed, their characteristics and their appearance
What will these rock characteristics impact?
How the rock survives under erosional and weathering processes
Define igneous rocks.
Rocks that form when magma from mantle cools down and hardens
longshore drift
The movement of water and sediment down a beach caused by waves coming into shore at an angle. the uk moves material from west to east
how are beaches formed
when material is transported by longshore drift and deposited by constructive waves.
where are sandy beaches found
sheltered bays, they have shallow gradients
describe a spit, and explain its formation
narrow ridge of shingle stretching out into coastline, forms due to longshore drift at a change of coastline. shingle gets deposited
tourism affecting the coastline
coasts often managed for tourists (with groynes etc)
infrastructure affecting the coastline
roads/railways/shipping ports/oil refineries.
construction affecting the coastline
dredging the sea to construct ports can have adverse affects on wildlife. they can also adjust the sediment cells
agriculture affecting the coastline
farmland will be impacted due to sea level rise because of increased coastal erosion because it’s low economic value and low priority in management
what is a storm/storm surge
large increase in sea level due to a storm. strong winds drive up the waves, whilst low pressure allows the sea level to rise up 3m above normal.
hold the line
maintain the existing coastline with defences
managed realignment
allow the shoreline to change naturally, but manage the process and the impacts
advance the line
build new defences on the seaward side
sea wall
-protects base of cliff. made of resistant concrete that deflects energy
-expensive and ugly, restricts access
groynes
-maintain a wide beach and attract tourists
-high maintenance cost, could impact other areas of coastline in sediment starvation
beach replenishment
-looks natural, attracts tourists, cheap
-material easily eroded and needs constant replenishment
waves
caused by friction that is generated when wind blows across the surface of the sea
destructive waves
strong winds, powerful waves, cause coastal erosion. tall, steep. backwash stronger than swash, so material is carried out to sea
constructive waves
light winds, cause deposition not erosion. stronger swash, so material is deposited on the beach
attrition
small rocks collide with eachother. break up, becoming smaller and rounder, until the rock becomes sand
abrasion
rocks thrown against the coastline. wears the coastline away over time
hydraulic action
large waves break against the cliff. water forced into the faults/cracks causing immense pressure. when it is released, it produces a force that makes the crack wider.
solution
chemicals in the sea react with the rock so it dissolves. occurs mainly with limestone.
discordant coastline
bands of different rock strengths run 90degrees to coastline. in dorset, clay, chalk and limestone form a discordant coastline
concordant coastline
bands of rock run parallel to the coastline
headland
rocks of higher resistance erode slower. as a result, high resistance rocks protrude out producing headlands
bays
formed in the same way as headland. constructive waves often bring sediment to form a beach.
cliffs
made through the process of hydraulic action and abrasion. destructive waves create a wave cut notch. as the notch gets eroded, the cliffs above become unstable, collapse, and are removed by waves
wave cut platform
below a wave cut notch, an area of exposed rock is left, which is not smooth. it continues to get eroded
cave
destructive waves break against the cliff face. hydraulic action widens the crack, eventually widening enough to form a cave
arch
waves erode the cave via abrasion and hydraulic action, which cause them to break through the middle of it forming an arch
stack
continued erosion on the base of the arch weakens it until the roof collapses, leaving a stack like Old Harry Dorset
mechanical weathering-freeze thaw
water enters cracks and in cold climates, freezes, expanding by around 10%. pressure weakens the cliff face.
chemical weathering
acid rain contains carbonic acid which dissolves limestone
biological weathering
roots of plants and trees, burrowing animals and nesting birds all weaken the rock
slumping
after rainfall, permeable rock becomes heavy and slips to a permeable rock in rotations
rock falls
sudden fall of rocks often due to prior weathering or growing a wave cut notch which resulted in an unstable cliff face
sliding
same as slumping but occurs on a bedding plane or a flat surface
sedimentary rocks
layers ontop of eachother, trapped water squeezed out
metamorphic rocks
rocks that change via heat/pressure
granite-gneiss
shale-slate
igneous rocks
intrusive magma cools inside volcano, big grains-granite
extrusive lava forms outside volcanoes small grains-basalt, pumice
uk rock types
tees exe line-
north/west=more faults, more resistant, granite
south/east=less resistant, chalk, clay, limestone
tectonic processes
in the pennines the UK’s plate moved north away from the tropics , which uplifted rock from beneath the sea to form land.
plucking
base of a glacier melts because of pressure and friction. water freezes in cracks and when glacier moves, it leaves behind chunks.
how do u-shape valleys form
ice sheets and glaciers alter v shaped valleys into u shaped valleys and leave behind post-glacial rivers
the lake district
upland
-igneous/metamorphic
-highest point=scaffell pike at 980m
-freeze thaw weathering
-landslides common
-river misfits deposited alluvium in valley bottoms making them fertile for farming
human alteration to the yorkshire dales
-cleared rocks made dry-stone walls
-norse settlers farmed areas and cleared glacial rocks for farming in the 8th century
human alteration to south downs
-arable farming on lower slopes became mini ecosystems for animals
-large leaved lime woodland now cleared
-3 towns attract walkers and riders
drainage basin of a river
source
tributary
confluence
drainage basin
watershed
main river channel
mouth
tributary
river or stream flowing into a larger river
confluence
the junction of two rivers, where one meets another
drainage basin
the area of land drained by a river
watershed
area of land which separates water flowing into different rivers
lower course
-large discharge
-wide
-deep
-high velocity
-huge sediment load
-small particles
middle course
-medium discharge
-increasing width and depth, velocity and sediment load
-decreasing particle size because of attrition
upper course
-shallow
-little discharge
-low velocity
-low sediment load
-large sediment particle size
suspension
light material carried by a river
saltation
small pebbles and stones bounce along the riverbed
traction
large boulders rolled along the riverbed
delta formation
-river splits into dis-tributaries
-bars build up in the middle of the main channel
-river slows as it approaches the sea and the river becomes less efficient because the hydraulic radius drops
surface runoff
rain that flow over land before reaching a channel
groundwater flow
part of streamflow infiltrated ground has entered an been discharged into the stream channel via seepage water
interception zone
rain never enters soil because it is intercepted by trees
transpiration
plants absorb water and give off vapour
infiltration
water on ground enters soil
natural levee formation
-form beside the river bank where it first floods
-river reaches bankful and deposits sediment where flow is slower, building a bank
artificial levee formation
built by engineers to prevent flooding
slow mass movement
soil creep dislodges tiny particles to move down
rapid mass movement
landslides and mudflows because sides are steeper, and rainfall
v shaped valley formation
As the river erodes vertically down over it leaves behind valley sides that are shaped like a letter V. This is because as it erodes straight down it leaves very steep valley sides that are then attacked by weathering processes such as freeze thaw and biological weathering. This weakens the valley sides which may collapse or move down slope due to mass movement processes such as slumping or soil creep. The river can then erode this material and move it away, leaving behind the characteristic V shape.
interlocking spur formation
-as river cuts vertically into the limestone, it produces steep sides and winds around areas of more resistant rock
-produces ridges of land which jilt into the river valley, looking interlocked
floodplain formation
-lateral erosion causes meanders to migrate across a valley floor and make it wide and flat
-floodwaters spread across the valley floor
-less energy for transport and alluvium deposited
meander formation
-heliocidal flow means thalweg moves laterally
-thalweg directed to outside of the bend, undercutting the bank and creating a river cliff
-sediment deposition caused by slow flow on outer bend
flood relief channel
diverts river. very expensive
dredging
increases channel depth
increases flood risk downstream
levees
allow safer riving nearby. very expensive
flood walls
useful, cheap, one off, useful for cramped cities
river channel restoration
meanders built to slow down water. improved ecology
floodplain retention
lowering floodplain
population growth in london caused by
1.rising birth rate because of more 20s mothers, women from the 70s choosing to have children in their 40s and migrant women having higher fertility rates
2.net immigration
main causes of large immigrations
1-EU membership, allowing free movement between other countries
2-globalisation-london’s knowledge economy attracting highly qualified/skilled workers
characteristics of the rural periphery
-low population density
-older populations
-lower incomes (farming/tourism, seasonal and minimum wage)
-high transport cost
-migration away of younger people
enterprise zones to reduce urban/rural differences
-uk government offers help with startup costs, access to superfast broadband and reduced profit tax
-24 in 2015
-driving force of local economies, create jobs
-attract more FDI, bring jobs across England
UK regional development grants reducing differences between rural and urban areas
-available over more of the UK with most in scotland, ireland and wales.
-include grants to help businesses start up.
change in industrial structure over time
1918- construction reduced because of WW1
1981-energy and water employment went down because coal mines shut own
the domino effect
in the 1960’s over 100k men worked in coal mining in yorkshire. coal was supplied to steelworks in sheffield, and used in shipbuilding.
-as one industry collapses, it leads to the collapse of others. this led to de-industrialisation across the north of england
jobs in yorkshire in the 90s
mainly mining and coal, now nobody mines
however, the brass band has a 1m recording contract
changes to the UKs primary and secondary sectors since 1980
-jobs in primary sector halved
-coal mine employees were 250,000 in the 70s, now 4000.
-farming lost 100,000 jobs from 1980 to 2015
the new economy
-london involved in more globaltrade and investment and has a huge number of quaternary and tertiary jobs
the knowledge economy
-requires degrees, specialist training etc.
the new rural economy
-wifi makes it easier for people in rural areas to work in an urban setting
situation of london
-wide, flat floodplain to build on
-vulnerable to flooding
-timezone allows trade with the whole world at some point during the day
why has immigration become an economic necessity for london
-skilled workers take up well payed jobs in the knowledge economy in the city.
-london companies employ people with specific skills from overseas.
how does migration affect different boroughs
-african/carribean migrants move into cheaper boroughs like newham/lambeth increasing diversity
-non diverse areas are like chelsea where house prices are higher
newham
-9,372/32,844 most deprived
-65%black, african, carribean, asian.
-64% government aided housing
-38% child poverty rate
-
richmond
-16,291/32,844 least deprived
-middle class, skilled pop, high income
why did industry and shipping decline in london
-containerisation common since 70s
-now ships too big for the shallow london port
-industries that relied on the port have to relocate
-manufacturing employees fell from 30% in 1970 to 7% today
brownfield sites
former industrial areas that have been developed before
regeneration
redeveloping former industrial areas
studentification
the change of an area because of the increase in students/schools/student flats
gentrification
older run down areas become culturally desirable
pros of a greenbelt
lack of greenfield sites mean brownfield sites are more likely to be developed
-they have stopped urban sprawl to help conserve rural areas
cons of a greenbelt
they can be partly blamed for high house prices
they create longer commuter journeys
how is reurbanisation happening in london
-closure of docks made space for new development
-large TNC investment like HSBCs global HQ
-gentrification
-studentification
sustainability stool
environmental, social, economic
sustainability quadrant
equity-does it benefit everyone
futurity-will it last
environmental-is it eco friendly
public participation-is it bottom up
london improving employment
-working at home encouraged by many companies. amount doubled from 4-8%in 2012
london improving energy efficient housing
bedZED in sutton promotes energy conservation in 100 apartments and houses, and workplaces. 81% less energy for heating, 45% less electricity and 60% less water. recycle 60% waste.
650,000daily commuters to london
pros- creates building jobs, meets demands for jobs
cons-pressure to build houses, increased congestion, rise in house prices
cornwall situation
-12th largest county in UK but only 140people/km^2
-poor transport links: no motorway
-4.5m visitors contribute to 25% GDP
cornwall problems
-38% villages have a doctors office
-nearest hospital could be 30 miles away
-buses only serve 70% rural villages
-students may have to travel 30miles to sixth form
the eden project
-geothermal power license provised 4000 homes with electricity
-but, 97% visitors arrive by car, and there are few return visitors
