topic 4-physical landscape Flashcards
the UK landscape coastal changes and conflict formation of coastal features
tee-exe-line
separates the north and the south of the UK from the lowland in the south and highland in the north
upland areas are located in the
north-west of the UK eg Scotland
lowland areas are located in the
south-east of the UK
rock type in the lowland area
sedimentary rocks eg chalk erode easily
rock type in the upland area
ingenious rocks eg granite
land in the lowland is
low-lying flat formed by deposition of material eroded by glaciers
gentle relief
land in the upland areas is
steep relief
rocky
high above sea level
what is lowland mainly used for
arable farming
agriculture
this is because the soil is fertile and gentle relief
what are upland mainly used for
sheep farming
forestry - coniferous trees
difficult to grow crops
formation of sedimentary rocks
sedimentary rocks are formed when layers of sediments have been deposited in layers -strata. these layers of sediments are compressed together until they create sedimentary rocks eg chalk and limestom=ne
examples and formations of sedimentary rocks
Carboniferous limestone
- formed from shells and skeletons of dead marine organisms
- quite hard
clays and shale
formed like limestone but softer
clay is very soft made from mud and clay minerals
widely found in the lowland areas of England - north-west
formation of igneous rocks
due to volcanic activities .igenous rocks are formed when molten rocks from the mantel cool down and harden this occurs at conservative plate boundaries
example of igneous rocks
granite very hard and resistant
where are sedimentary rocks found
in the low land areas of England
where are igneous rocks found
found mainly in the upland areas scattered across Scotland, in the lake district and northern Ireland, northern wales
metamorphic rock
when other rocks eg sedimentary and igneous rocks are changed by heat and pressure ( the intense heat and pressure caused by plate collision forms hard metamorphic rocks)
where are metamorphic rocks found
found in large bands across Scotland and Northern Ireland and wales
example of metamorphic rocks
marble - very hard
shale becomes slate
slate becomes schist
what are the main ways The main ways that tectonic activity has shaped the UK landscape are:
plate movement
plate collisions
volcanic activities
how did active volcanoes shape the UK active volcanoes
the UK used to be much closer to a plate boundary. active volcanoes at this boundary erupted magma in the UK which cooled to form igneous rocks such as granite
how did plate collision form the shape of the UK
caused the rocks to be uplifted and folded forming mountain ranges. the intense heat and pressure caused by the plate collision formed hard metamorphic rocks
how did plate movement shape the Uk landscape
millions of years ago the UK was nearer to the tropics at this point, high sea levels were higher and so carboniferous limestone ended up forming in the warm shallow sea
Characteristics of Different Rock Types- carboniferous limestone
limestone is heavily affected by carbonation weathering which happened along the joints of the rock
permeable therefore forms dry valleys and resurgent rivers
Characteristics of Different Rock Types- chalk and clay
forms in escarpments in the UK lowlands
clays are softer than chalks
clays form wide valleys because it is easily eroded
Characteristics of Different Rock Types-slate and schist
slate is hard and resistant because it forms in layers
schist are bigger crystals
Characteristics of Different Rock Types-granite
very hard and resistant forms in upland areas
granite is impermeable which forms moorlands
Physical Landscape Processes
Erosion processes weathering post-glacial processes slope processes physical process affected by weather
Erosion processes
Erosion is the wearing away of rocks as a result of being picked up and moved elsewhere.
weathering processes
Mechanical, chemical and biological weathering describe the breakdown of rocks into smaller pieces
slope processes
slope processes include mass movement and soil creep.
Post-glacial river processes
melting ice at the end of glacial periods made rivers much ,more bigger
Human Landscape Processes
settlements
agriculture
forestry
settlements
many factors have influenced where settlements have been built for example areas with good water supply or easy defences and good shelter
agriculture
land has been cleared to make space for agriculture
Hedgerows and walls have been installed to mark out field boundaries.
foresty
Large areas of deciduous woodland have been replaced by coniferous forests, which are managed for their timber.
mechanical weathering is also known as freeze-thaw weathering
freeze-thaw weathering water gets into the cracks of rocks. water freezes and expands by 10 per cent putting pressure on the rock and when the temperature warms up the frozen water melts causing the rocks to break up
chemical weathering
rain water is acidic so when rain falls on rocks like limestone a chemical reaction takes place which causes the rocks to weaken and dissolve
biological weathering
is the breakdown of rock by living things
eg plant roots break down rocks by growing into cracks and pushing them apart
mass movement
is when material falls down These movements are caused by weathering, erosion, and gravity. Small changes over time can mean that a cliff's centre of gravity hangs over the sea, instead of over land. slope rockfalls slumps slide
mass movement - rockfalls
when material break and crumble down the cliff
mass movement - slides
when material move down a slope in a straight line
mass movement - slumps
when material shift with rotation
waves wear away the cost using 4 processes of erosion
abrasion
attrition
hydraulic action
solution
processes of erosion - hydraulic action
is where the force of the water hits against rocks and compresses the air in the cracks this puts pressure and causes the rock to break off
processes of erosion - abrasion
when waves pick up small pieces of material eg sand/pebbles which get scrapped and rub against the surface of the rock which wears the rock away
processes of erosion - attrition
eroded pieces of rock material are moved by the wave and smash into each other. This causes them to break apart and become smaller and more rounded.
processes of erosion - solution
seawater dissolves some of the rocks minerals causing a disintegration of rocks eg limestone
types of Wave
constructive and destructive
what are constructive waves
features of constructive waves
constructive waves build up the beach by depositing material
strong swash and weak backwash
they are low and further apart
form gentle beach slope
have limited energy
occurs during the summer time
what are destructive waves and the features of them
destructive waves destroy the beach by carrying the sand away from the beach
strong backwash which removes sediments and a weak swash
a steep beach profile
more energy
occurs during the wintertime
due to strong backwash waves are higher and have a steeper gradient
longshore drift
is the process which transport material along the coastline
the process of longshore drift
wind approaches the coast at an angle due to prevailing winds
the waves are controlled by these winds, so this angle would be the direction the swash carries material up the beach
gravity is the only force that acts on the backwash so the backwash carries the material down the beach a right angle back toward the sea
overtime the material zigzags along the coast
deposited sediments can form
bars and spits
formation of a bar
a bar is formed when a spit joins 2 headlands together. lagoons are often created behind the bar
formation of a splits
a spit forms at sharp bend in the coastline
longshore drifts transports sand and shingle past the bend and deposits it in the sea
strong wind and waves recurve the end of the spit
overtime sheltered area become marshland
What are the Effects of Human Activity Have on Coasts?
industry
costal management
develpoment
agriculture
agriculture
agricultural land is less valuable and cheaper. it is often left unprotected so farmland could be lost as costal erosion destroys the land
Direct effects are immediate consequences of human’s behaviour. examples are
coastal management has a direct impact on the coast.
coastal defences aim to reduce erosion and weathering. hard engineering management strategies protect the coastline from seas erosion and destructive waves and coastal defences reduce erosion.
industry
industrial growth has led to an increased pressure to build on salt marshes .these areas provide low-flat land which is ideal to build ports and industry but can lead the land more vulnerable to erosion
direct and indirect on industry
direct - more costal defences because coastal areas are popular areas to live/work so people want to protect their homes and business
indirect- this can effect the deposition and transportation of material so could make the land more vulnerable to erosion
direct effect
building coastal defences to prevent erosion
indirect effect
make the land more valuable to erosion
what climate change in increasing the risk of coastal flooding
storm frequency - storm surges could be more frequent
rising sea levels -pose a threat to low-lying and coastal areas
one way coastal flooding poses a threat to people
low-lying areas could permanently be flooded which could make it impossible to inhabit and infrastructure and tourism can be destroyed by floods.
one way coastal flooding poses a threat to the environment
seawater has high salt content and due to increased coastal flooding can damage the ecosystem and can affect the agricultural land by reducing soil fertility
hard engineering
man-made projects built
involves major constructions
tends to be more expensive
soft engineering
works with natural processes
cheaper and need little maintenance
provides habitat for wildlife
example of hard engineering coastal defences
sea wall
groynes
example of soft engineering coastal defences
beach replenishment
Over time, cliffs are eroded by destructive waves, resulting in the formation of wave-cut platforms. This process is described below:
- destructive waves cause the most erosion at the base of the cliffs
- eventually, this erosion causes a wave-cut notch to form
- continued erosion of wave-cut notch causes the rock above to become less stable and eventually collapse
- the collapsed material is washed away and a new wave-cut notch is formed
- repeated collapsing results in the cliff retreating
headlands and bay are formed on which coastline
discordant coastline
the formation of headland and bays
headlands and bay are formed on the discordant coastline.
- soft rocks with lots of cracks and joints have a low resistance to erosion
whereas hard rocks have a high resistance to erosion
- when the sea hits both the soft and hard rocks the more soft rocks erode easily
-the soft rocks erode inwards forming bays
the hard rocks that erode more slowly is called a headland
s headlands are eroded, these landforms can be created:
caves
stack
arches
concordant coastline
on a concordant coastline the alternating bands of hard and soft rocks are parallel to the coast
formation of a cave
waves crash into the headlands and enlarge the cracks and joints. When the cracks get wider due to hydraulic action and abrasion they become large enough to form a cave
formation of an arch
repeated erosion and enlargement on the cave would eventually deepened the cave until it breaks through the headland forming an arch
formation of stack
when the top of an arch collapse due to graving leaving an isolated rock known as a stack
What type of waves is responsible for most of the erosion that takes place at the base of cliffs?
Destructive waves
