Paper 2 Flashcards
The Cheshire plain
Area of low, flat land formed by deposition of material eroded by glaciers.
The land is fertile, and used for farming
North west england
Grampian Mountains
Part of the highlands and home to Ben Nevis (highest mountain in uk)
The mountains are steep, rocky and sparsely populated
Found in Scotland
Snowdonia
Is a Glaciated upland area formed from rock from extinct volcanoes.
Contains steep mountains and glaciated valleys
The downs and the Weald
A lowland area with a wide valley situated between the parallel hills.
Now mainly agricultural
Igneous rock
Formed when molten rock from mantle cools and hardens and the rock forms crystals as it cools.
E.g. Granite
Sedimentary rock
Formed when layers of sediment are compacted together until they become solid rock.
E.g. carboniferous lime stone and chalk which are formed from tiny shells and skeletons of dead sea creatures (limestone is hard and chalk is soft)
Also, clays and shales are made from mud and clay materials and are soft.
Metamorphic rock
Formed when other rocks are changed by heat and pressure. The new rocks formed are harder and more compact
E.g. shale and marble
Harder rocks
- Carboniferous limestone
- slate and shale
- schist
- Igneous rocks
Softer rocks
- Clays
- sandstone
- Chalk
Active volcanoes
Forced magma through the earths crust back when the UK used to be closer to a plate boundary, which cooled to form igneous rocks. (Granite)
Plate collisions
1) caused rock to be folded and uplifted, thus forming mountain ranges (granite which is resistant to erosion)
2) the intense heat and pressure caused by plate collisions formed hard metamorphic rocks
Plate movement
1) a long time ago, britain was in the tropics and was partially under water (forming carboniferous limestone) in warm shallow seas
2) the youngest rocks which are the chalks and clays formed in shallow seas and swamps
Granite characteristics
Very resistant and forms upland landscapes
Has lots of joints and cracks which in these places the rock wears away quickly
Granite is impermeable (doesn’t let water through)
Slate and schist characteristics
Slate forms in layers, creating weak planes in the rock
Generally very resistant to weathering
Schist has bigger crystals than slate and splits easily
They often form upland landscapes and are impermeable
Carboniferous limestone characteristics
Rain water slowly eats away at limestone through carbonation weathering. This creates limestone pavements…
Limestone is permeable
Chalk and clay characteristics
Chalk is harder than clay (it forms escarpments) in UK lowlands
Chalk is permeable
Clay is very soft and easily eroded (wide flat valleys)
Clay is impermeable
Weathering
Is the breakdown of rock into smaller pieces. It can be mechanical, chemical or biological
Erosion
Wears away rock. During last glacial period, ice eroded the landscape. And now rivers do as well
Post glacial river processes
Melting ice at the end of glacial periods made rivers much bigger than normal with more power to erode landscape. The ice also left distinctive landforms when melted
Slope processes
Including mass movements, e.g. rockfalls slides soil creep
Physical processes are also affected by the climate
For example, a cold climate increases the likelihood of freeze thaw weathering and a wet climate increases the number of rivers…
How have humans changed the landscape through agriculture
Cleared forest areas to make space for farming
Hedgerows have been made to mark out fields
Different types of farming (arable for crops, dairy, sheep…)
Mechanical weathering
Is the breakdown of rock without changing its chemical composition.
Salt weathering- 1) sea water gets into cracks in rocks
2) when water evaporates, crystals are left and they
expand which puts pressure on the rock and this
Process repeats, thus breaking up the rock.
Chemical weathering
Is the break down of rock by changing its chemical composition.
E.g.- Carbonation weathering (sea water and rain has carbon dioxide disolved in them, making them weak carbonic acids and this reacts with the rock that contains calcium carbonate so the rock is disolved by the water)
Biological weathering
Is the breakdown of rock by living things (plant roots, which grow into cracks in rocks and push them apart)
What is mass movement
Is the shifting of rock and loose material down a slope as the force of gravity acting in it is greater than the force supporting it
Coasts retreat rapidly
Most likely when wet due to increased mass and water acting as lubricant
Three types of mass movement
Slides
Slumps
Rockfalls
Mass movement- Slides
Material shifts in a straight line
Mass movement- Slumps
Material shifts with a rotation
Mass movement- Rockfalls
Material breaks up and falls down the slope
Three processes of erosion via waves
Hydraulic power, abrasion, attrition
Hydraulic power
Waves crash against the rock an compresses the air in the cracks. This puts pressure on the rock and repeated compression widens the cracks and makes bits of rock break off.
Abrasion
Eroded particles in the water scrape and rub against rock, removing small pieces.
Attrition
Eroded particles in the water smash into each other and break into smaller fragments. Also, the edges get rounded off.
Discordant coastlines
Are made up of alternating bands of hard and soft rock that are at right angles to the coast
This forms headlands and bays as different rocks erode at different rates
Concordant coastlines
The alternating bands of hard and soft rock run parallel to the coast so erosion will happen at the same rate throughout the whole coast
Destructive waves
These waves, which are high, steep with a high frequency carry out erosional processes and have a stronger back wash than swash
Formation of a wave cut platform
- a lot of erosion occurs at foot of cliff
- this forms a wave cut notch
- rock above becomes unstable and colapses
- collapsed material is washed away
- repeated collapsing results in the cliff retreating
- this leaves a wave cut platform
Headland and bay formations
1) soft rocks with joints are eroded easily and hard rocks are a lot more resistant
2) headlands and bays form due to alternating bands of hard and soft rock
3) less resistant= erodes quickly (bays)
4) more resistant= erodes less quickly (headlands)
Headlands ➡️ caves ➡️ arches ➡️ stacks
1) headlands made up of resistant rock which has cracks
2) waves crash into cracks and enlarge them via hydraulic power and abrasion
3) repeated erosion and enlargement results in a cave forming
4) continued erosion deepens the cave until eventually it breaks through, which forms an arch
5) erosion and weathering wears the supporting rock away of the arch and forms a stack
Long shaw drift process
1) waves follow direction of prevailing wind
2) waves usually hit at an oblique angle
3) swash carries material up beach
4) back wash carries material back down
5) over time material zig zags along coast
Constructive wave deposition
1) deposition is when material that is being carried by sea water is dropped on the coast as the water slows and loses energy
2) waves that deposit more material than they erode are constructive waves
3) constructive waves are low, long and have a low frequency
4) swash is more powerful than back wash
5) they deposit sand and shingle
Spits
1) spits form on sharp bends in the coast line
2) long shore drift transports sand and shingle past the bend and deposits it in the sea
3) strong winds can cause a recurved end
4) sheltered area behind spit allows plants to grow there as material accumulates (salt marsh and mud flat)
Bar
1) a bar is formed when a spit joins 2 headlands together
2) the bar cuts off the bay between the 2 headlands from the sea
3) a lagoon can form behind the bar
Humans activities direct effects on the coastline
Are the immediate result of human activities.
Humans activities indirect effects on the coast
These happen due to direct effects. E.g. building coastal defences will prevent erosion in one place but it can increase it in other places.
Agriculture near the coast
They have low economic value so are often left unprotected
Changing the way farmland is used can affect stability of cliffs and clearing vegetation can make soil unstable
Development near the coast
Coasts with a lot of development may have more coastal defences
However this can restrict sediment supply to lower beaches (cliffs vulnerable to erosion)
Industry near the coast
Exposing large areas of rock (due to quarries) poses risk of erosion as there is less protection (of gravel)
Coastal management
Protects coastal landscapes yet reduces protective material further along the coast (increases erosion further down coast)
Yet prevents coastal retreat in some places
How is coastal flooding becoming more likely
Rising sea levels- pose risk to low lying areas, higher tides could increase erosion due to removed material
Storm frequency- storms will be more frequent due to climate change, sea will be more powerful
Coastal flooding threats to people and environment
1) permanently flooded areas
2) industries may be shut down
3) damaged infrastructure
4) decreased tourism
1) ecosystems affected due to sea waters high salt content
2) force of flood water could uproot trees and plants
3) conservation areas are threatened by coastal erosion
Hard engineering
Man made structures built to control the flow of the sea and reduce flooding and erosion
Soft engineering
Schemes set up using knowledge of the sea and its processes to reduce its effects of flooding and erosion (natural)
Rivers’s course
The path of a river as it flows downhill
Rivers upper course
Very steep
V-shaped valley with steep sides. narrow and quite shallow channel
Rivers middle course
Medium gradient
Gently sloping valley sides and wider and deeper channel
Rivers lower course
Gentle gradient
Very wide, almost flat valley. vey wide, deep channel
Vertical erosion of a river
This deepens the river valley and channel making it V shaped. This is dominant in the upper course. High turbulence causes rough, angular particles to be scraped along river bed, thus causing downwards erosion
Lateral erosion of river
This widens the river valley and channel during the formation of meanders. Dominant in middle and lower course of river.
Four processes of erosion that occur at rivers
Hydraulic action- force of water breaks rock particles away from river channel
Abrasion- rocks picked up by river rub against the channel
Attrition- eroded particles picked up by river smash into each other
Solution- river water dissolves some types of rock (chalk and limestone)
Traction of eroded particles in river
Large particles like boulders are pushed along the river bed by the force of the river
Saltation of particles in river
Pebble sized particles are bounced along the rover bed by the force of the water
Suspension of particles in river
Small particles like silt and clay are carried along by the water
Solution of particles in river
Soluble material dissolve in the water and are carried along
Reasons why rivers slow down and deposit material
1) volume of water in river falls
2) amount of eroded material in water increases
3) water is shallower
4) river reaches mouth
Formation of a waterfall
1) waterfalls form when a river flows over an area of hard rock followed by an area of soft rock
2) soft rock is easily eroded (hydraulic action and abrasion)
3) this creates a steep drop as the soft rock is eroded more
4) hard rock is eventually undercut, is unsupported and will eventually colapse
5) the eroded particles will swirl around at the bottom due to abrasion create a deep plunge pool
6) more undercutting will cause the water fall to retreat
Inter locking spurs
1) in upper course the river erodes vertically
2) river channel is forced around the bends in hill side as the river is not powerful enough (forming interlocking spurs)
Meanders
1) current is faster on outside bends (deeper)
2) more erosion occurs on outside bends (river cliffs)
3) because the inside is slower, material is deposited on the inside bend, thus forming a slip off slope
Formation of an ox-bow lake
1) erosion causes outside bends to get closer together
2) the neck could break through this small bit of land (during flood)
3) the river will now flow through the shortest path
4) deposition will eventually cut off the meander, thus forming an ox-bow lake
What is a Flood plain
Is the wide valley floor on either side of a river which occasionally gets flooded.
Material will be deposited her during a flood
Levees
Are natural embankments (raised edges of a river channel)
During a flood, eroded material is deposited over the whole flood plain and heavy material will be deposited closest to the river channel (over time material will begin to build up (creating levees along the edges of the channel)
Deltas
Low lying areas where a river meets the sea or a lake
(River slows down towards the mouth and material is deposited and the channel will split up into distributaries and eventually after more material builds up low lying areas of land are formed called deltas)
What helps shape river landscapes
Climate, geology, slope processes
Storm hydrographs
Show the changes in the river discharge around the time of the storm
What factors affect storm hydrographs
Geology- rock type (impermeable or permeable) Soil type Slope Drainage basin type Urbanisation Deforestation
Why has risk of flooding increased in Uk
Increased frequency of storms
Land use change (urbanisation and deforestation…)
Flooding threats to people
1) people killed or injured
2) destroyed infrastructure
3) lack of clean drinking water
4) possessions damaged
5) businesses shut down
Flooding threats to environment
1) contaminate rivers due to sewage…
2) farm land ruined
3) uprooted trees/plants
Engineering to reduce risk of flooding or the effects
Flood walls- artificial barriers (hold water) built along river
Embankments- high banks to stop river flowing into built up areas during flood (protect buildings…)
Flood barriers/gates- stop flooding from storm surges (protect large areas of land)
Flood barriers- temporary protection
Flood plain retention- (flood plain can store water if nothing is built on it)
Where is population density highest
Cities (urban core)
Where are areas sparsely populated
Upland rural areas
How do uk aim to reduce differences in wealth
1) creating enterprise zones- encourage companies to relocate to areas of high unemployment bringing jobs to help poorer areas develop
2) transport infrastructure- faster journeys into big cities (job opportunities for people in rural areas)
3) regional development- promotes growth in poorer and rural areas (small high tech businesses, thus providing training)
