paper 1: 1.1 the changing landscapes of UK Flashcards
how are sedimentary, igneous and metamorphic rocks formed?
sedimentary- formed in layers
igneous- magma
metamorphic- extreme heat and pressure
examples of sedimentary, igneous and metamorphic rocks.
sedimentary - sandstone, chalk, limestone
igneous - granite and basalt
metamorphic - slate and schist
which sedimentary, igneous and metamorphic rocks have crystals or fossils
sedimentary - fossils
igneous - formed of crystals
metamorphic - deformed fossils
where are sedimentary, igneous and metamorphic rocks located in the UK?
sedimentary - south-east
igneous - north-west
metamorphic - north-west
are sedimentary, igneous and metamorphic rocks located in upland or lowland areas
sedimentary - lowland
igneous - upland
metamorphic - upland
tectonic plate action in the uk
plate movements caused mountains (folds) and faults in the rocks
what does glacial erosion and deposition cause?
erosion carve out corries and u-shaped valleys
weathering- what does freeze-thaw form
it breaks off rocks, which forms scree slopes
climate of the UK in urban Places
high levels of precipitation causes high levels of surface runoff over impermeable surfaces
how does river erosion form uk landscapes
meandering rivers erode wide valleys
how does river deposition form uk landscapes
forming floodplains and levees
slope processes
mass movement (landslides) and soil creep (gradual movement downhill) cause cliffs to collapse
how have farming changed landscapes
hill sheep farming in upland areas and arable farming in fertile lowlands
How has forestry changed landscapes
- upland landscapes have been planted with trees for forestry
how have settlements changed landscapes
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- deforestration
- wetlands are drained
- valleys are flooded to create reservoirs
- more surface runoff due to more impermeable surfaces
what is weathering
the breaking down of rocks in situ
name the three types of weathering and their examples
chemical - acid rain
mechanical/physical - freeze-thaw weathering
biological- animals burrowing
What is Mass Movement, give two examples.
the downhill movement of mass due to gravity
sliding and slumping
types of erosion
- hydraulic action
- abrasion
- attrition
- solution
types of transportation
- traction
- suspension
- saltation
- solution
what is longshore drift?
longshore drift is the process by which sediment is transported up the beach (swash) at an angle (direction of the prevailing wind) and straight down the beach at right angles due to gravity (backwash)
what does deposition do to coasts and what type of waves
builds up the coast as the wave loses energy, mostly when constructive waves are present
what are concordant coasts
same type of rock parallel to the coasts
what are discordant coasts and what do they form
alternating bands of different types of rock perpendicular to the coast, forms headlands and bays.
what are joints and faults and what is there effect on the rate of erosion
joints are smaller cracks, while faults are much larger weaknesses
more likely to erode quickly
what type of energy do constructive and destructive waves have and when do they form
constructive waves have lower energy and form in calmer conditions, while destructive waves have higher energy and form in stormy conditions
what does constructive waves do to the coast
builds up the coast by depositing materials
when do destructive waves occur and is the swash or backwash stronger
they occur when there is a longer fetch and stronger wind has been blowing for a great amount of time
the swash is weak and the backwash is strong.
how does the uk’s seasonality affect coastal erosion
colder temperatures leads to freeze-thaw weathering to happen at a faster rate and stronger waves accelerate coastal erosion
what type of winds and waves does the storm frequency provide coasts with?
stronger winds and destructive waves
what does heavy rainfall do, what 3 landforms can change
saturates cliffs and causes slumping
spits, sand dunes and beaches
which direction does UK’s prevailing winds come from, name one characteristic, where does it comes from
south-west
carries warm, moist air
over the Atlantic ocean
where do headlands and bays form
discordant coasts
name a hard and soft rock that forms headlands and bays
more resistant rock like chalk protrudes out to the sea forming headlands while less resistant rock like sand and clay erode more quickly forming bays
how does a headland change over time
- headland
- cave- hydraulic action and abrasion erode a joint or fault
- arch - forms when two caves erode from either side
- stack -when a arch collapses
- stump - when a stack cuts and falls off
how does a wave cut platform form
4
- first HA and abrasion form a wave cut notch in the base of the cliff
- it becomes larger
- top becomes heavy ad unsupported so collapses due to gravity
- wave cut platform visible at low tide
what are beaches
where does deposition occur
deposits of sand or shingle
in sheltered areas of the coastline, and wave energy is lower
what is a spit?
how are they formed?
are narrow beaches that are attached to land at one end and extend across a bay or estuary
a change in the coastline direction
what is a bar?
it is just like a spit but it is attached to land on both ends, connecting two headlands and turns the bay into a lagoon.
human activities can change coastal landscape
how has urbanisation lead to changes in coastal landscapes (2 reasons)
- building weight makes cliffs more vulnerable
- urbanisation increases the need for sea defences.
human activities can change coastal landscape
how has agriculture lead to changes in coastal landscapes (3 reasons)
- creates wildlife habitats
- increases sedimentation
- increases soil erosion
human activities can change coastal landscape
how has industry lead to changes in coastal landscapes (3 reasons)
- increases air, noise and visual pollution
- can destroy habitats for sea life and birds
- creates employment opportunities
human activities affects the environment and the people
what are the effects of coastal recession and flooding (5 reasons)
- loss of homes and businesses
- decreasing property values
- disruption to roads and railways lines
- cliffs become dangerous for people
- wildlife habitats can be destroyed
what does hard and soft engineering do
hard engineering protects the coastline but spoils the landscape.
soft engineering works with nature to maintain the coastline but is less effective
types of hard engineering
3 examples
- sea wall protect cliffs and building but are the most expensive option.
- groynes trap sand and build up the beaches but lead to increased erosion downdrift as the process of longshore drift is slowed down.
- rip rap absorbs wave energy. it is less expensive then a sea wall but restricts beach access.
types of soft engineering
2 examples
- beach nourishment reduces wave energy and is good for tourism
- managed retreat
what is the coast case study
name a headland
The Holderness Coast
Flamborough Head
coastal landscapes are outcomes of physical and human processes together
significance of location
what rock is prone to erosion and where is it located(named headland)
- softer bolder clay is easily eroded and prone to slumping following heavy rainfall. chalk is more resistant at Flamborough head
- it is exposed to strong wind from the north sea
coastal landscapes are outcomes of physical and human processes together
physical processes
3 processes and a named type of rock on the holderness coast
- coastal erosion- clay is easily eroded
- mass movement - clay slumps after periods of rainfall.
- transport - desctructive waves move sediment away from the coastline.
coastal landscapes are outcomes of physical and human processes together
human processes
what has hard engineering done to the environment
- hard engineering at mappleton have protected it from erosion.
- hard engineering has prevented transportation, making erosion worse in other places.
coastal landscapes are outcomes of physical and human processes together
changes
what are the changes in the landscape and environment
- some parts of the coastline are retreating by nearly 2 metres per year.
- framland, property and houses have been lost to sea.
what is sliding
rock and weathered material moves down a slope owing to gravity
what is slumping
a river erodes the bottom of a valley slope, making it steeper. the material above then slides downwards particularly if saturated
How does the gradient change as we go downstream
decreases- less vertical erosion more lateral erosion
How does the discharge change as we go downstream
increases- more bodies of water are adding into the river
How does the depth change as we go downstream
increases- more erosion
How does the channel width change as we go downstream?
increases- lateral erosion, hydraulic action
How does the velocity change as we go downstream
increases- less friction due to rounder rocks and smoother channels.
How does the valley profile change as we go downstream
decreases- steep sides, gentler sides to flat gentle sides
How do the features change as we go downstream, name 3 landforms
waterfall, meander and levees
How does the sediment shape change as we go downstream
becomes more rounder- abrasion
How does the sediment size change as we go downstream
decreases- attrition
How does the frequency of storms increase the risk of flooding
intense precipitation can cause rivers to overflow
How do periods of hot, dry weather increase the risk of flooding
hardens soil surface, meaning the water can’t be soaked in which increases surface runoff and river discharge.
impacts of climate on discharge
discharge will be greater in wetter climates.
less discharge in hotter climates as more evaporation
impacts of climate on erosion rates
erosion rates will be higher with greater discharge.
impacts of climate on transport rates
transport rates will be higher when the energy of the water is greater
impacts of climate on the weathering of rocks
the weathering of rocks will be greater where temperatures range from just above to below freezing
how are interlocking spurs formed?
at the source the river has limited energy and naturally flows around ridges of more resistant rock
how are waterfalls formed?
formed when there is a layer of more resistant rock over a layer of less resistant rock. the less resistant rock is eroded by hydraulic action and is undercut. the overhead protruding more resistant rock collapses forming a waterfall.
how are gorges formed?
over time as the waterfall retreats forming a gorge.
what are meanders?
bends in the river channel
what are river cliffs?
outside bend of a meander
what are point bars?
inside bend of a meander
how are oxbow lakes formed?
they form as the neck of the meander narrows and eventually erodes through. the water takes the quickest route cutting off the old meander causing it to dry out eventually.
how are floodplains formed?
it is shaped by meanders and lateral erosion, during a flood the river deposits sediment forming a floodplain.
how are levees formed?
as deposition continues during flooding eventually embankments will form on the banks of rivers.
human activities lead to changes in river landscapes
how does urbanisation lead to changes in the river landscapes?
- increases impermeable surfaces, increasing surface run off, increasing discharge.
how does agriculture lead to changes in the river landscapes?
- deforestation and field drainage transports water more quickly into streams
- water is extracted from rivers for irrigation
how does industry lead to changes in the river landscapes?
-reduce the amount of erosion
- chemical waste can pollute the river
how does rainfall intensity affect flooding
large amounts of rainfall reduces soil infiltration.
how does geology affect flooding
impermeable rocks means that water cannot percolate from above
how does snowmelt affect flooding
during spring snow melt adds more water to a river
how does drainage basin affect flooding
steep-sided valleys carry water into a river system quicker.
how does urbanisation affect flooding
more impermeable surfaces
how does deforestation affect flooding
less interception and greater surface runoff
the physical effects of flooding
soil erosion and loss of habitats
the human effects of flooding
loss of life and jobs, economic damage, damage to property, and disruption to farming and transport
why are dams and reservoirs built
barriers constructed to hold water. they store large volumes of water and can also be used to generate hydro-electric power.
disadvantage of dams and reservoirs
they are expensive and sand can build up in reservoirs
what does channelisation do
channelisation straightens or widens a river channel allowing water to flow more quickly from the area at a higher flood risk
disadvatages of channelisation
water moves quickly downstream increasing the flood risk to other settlements
soft engineering
what does floodplain zoning do
prevents development in areas at a higher risk of flooding. this reduces the number of homes at risk and allows infiltration to take place.
soft engineering
what are washlands
they are areas adjacent to rivers that are deliberately flooded in order to avoid flooding of residential areas and important farmland
river dee- human factors causing change
channelisation
has improved navigation but has increased velocity and discharge
river dee- human factors causing change
reservoirs
are constructed
river dee- human factors causing change
embankments
are built to protect agricultural land and property.
river dee- physical factors causing change
meanders
have caused bends in the river
river dee- physical factors causing change
rising sea levels
- rising sea levels could replace freshwater marsh landscapes
- in the dee estuary, it could destroy the landcape and habiats
- name a coastal landscape
- name two rivers
- swanage
- river creedy, river wye
