EDEXCEL GCSE GEOGRAPHY A TOPIC 1A AND 1B

Self-Made

What are the 3 main rock types?

sedimentary, igneous, metamorphic

what are sedimentary rocks?

rocks formed of small particles that have been eroded, transported and deposited in layers or from the remains of dead animals/plants e.g. chalk

what are igneous rocks?

rocks created by magma or lava cooling during volcanic activity, forming rocks with crystals. e.g. granite

what are metamorphic rocks?

rocks formed when other rock types are put under extreme pressure/heat. e.g. slate

what are uk upland landscapes formed from?

harder metamorphic and igneous rocks which erode at a slower rate

why are uk upland landscapes made from hard rocks?

tectonic processes caused molten magma to rise over the earth’s crust and solidified

what are uk lowland landscapes formed from?

softer sedimentary rocks which are less resistant

why are uk lowland landscapes formed from sedimentary rocks?

UK was submerged by a warm, shallow sea which deposited material

What does glacial erosion form?

U-shaped valleys and corries in upland landscapes

What does glacial deposition form?

moraines and drumlins

What does weathering form?

scree slopes

what does high precipitation cause in the north west?

many surface streams on impermeable rock

what do post-glacial rivers?

v-shaped valleys

how did climate affect lowland lanscapes

south downs was originally covered in permafrost and when it thawed it slumped down hill

what human activities result in distinctive landscapes?

forestry, agriculture, settlements

how did forestry affect uk landscapes

originally most of the uk was deciduous and coniferous but these trees have now been cut down for agriculture and settlement. Confiferous tree plantations are used but have limited biodiversity

how does agriculture affect uk landscapes

-grazing of sheep in upland prevents regrowth of trees and a moorland landscape

-in lowlands dairy and beef farming produce irregular green fields

-removal of hedgerows for large fields

-networks of straight drainage ditches

how does settlements affect uk landscapes

in upland areas, hamlets and villages are built from local materials

in lowland areas large towns and cities cover most the landscape

what is weathering

breakdown of rocks

what is erosion

breakdown of rocks and then it’s removal

what is mass movement

downslope transfer of material under gravity

what is mechanical weathering

breakdown of rock into smaller pieces of the same material

what is freeze thaw weathering

water enters the rock and freezes and the water expands, the ice is then melted and the crack is widened

what is chemical weathering

organic acid is slightly acidic and this breaks down the rocks overtime

what is biological weathering

breakdown of root due to plants and organisms, e.g. plant roots eroding rock

what is sliding

downslope movement of material along a straight shear plane

which rocks does sliding occur

hard rocks with a bedding plane

what is slumping

downslope rotational movement of rock along a curved shear plane

which material does slumping occur in

loose, unconsolidated material

what is mass movement increased by

rainfall where water soaks into rock increasing weight and lubricating particles, reducing friction

what is abrasion

occurs when waves throw carried load items against the cliff

what is hydraulic action

the force and weight of the water itself breaks rock off of the cliff as it collides with it

what is solution

occurs when seawater dissolves rock minerals

what is attrition

load items carried by waves are bashed against each other and breaks them down into smaller pieces

what is traction

rolls heavy load items along the seabed

what is saltation

bounces light load items off of the seabed

what is suspension

carries mineral ions dissolved within the seawater

what is longshore drift

occurs when waves approach a beach at an angle

when does deposition occur

when waves no longer have sufficient energy to continue transporting the resource

what does hard rocks tend to form?

headlands

what do soft rocks tend to form?

bays

what are joints

small fractures in the rock

what are faults

large fractures within the rock

what do joints and faults make a rock more susceptible to?

weathering, erosion and mass movement

what do rocks with joints and faults form?

caves, arches and stacks

what is a concordant coastline?

rock layers are running parallel to the coastline

what is a discordant coastline?

coasts have rock layers at an angle to the coastline

what are waves

produced by a transfer of energy from wind to sea by friction

what is wave energy determined by?

wind strength, wave fetch, wind duration

what is wind strength

waves with higher energy

what is wind fetch

uninterrupted distance of open water over which wind can blow

what happens when a wave reaches the shore?

friction with sea bed slows the wave down and the top topples forward

what is swash

water flowing up the beach

what is backwash

gravity drags water back down the beach when energy is exhausted

what are destructive waves

high energy waves with high wave height, usually about 11-15 per minute

what are the characteristics of a destructive wave?

strong backwash, weak swash. they plunge down at a steep angle producing a lot of energy

what landforms are produced by destructive waves?

caves, arches, stacks and narrow steep beaches

what are constructive waves

low energy waves with low wave height and come about 6-9 times a minute

what are the characteristics of a constructive wave?

strong swash, weak backwash

how do constructive waves deposit material?

strong swash brings material up the beach but the weak backwash leads to it being deposited

what do constructive waves produce?

wide beaches as they deposit material

what is the uk climate

temperate maritime climate with warm wet summers and mild wet winters

what does the seasonality of the uk climate cause?

freeze-thaw weathering in the summer

chemical weathering in the summer

higher rainfall in winter makes mass movement more likely

-weathering breaks bonds in the rock so erosion is more likely

-coastal retreat is greater in the winter

what does the storm frequency of the uk cause?

storms create higher energy winds with higher energy waves

high energy waves produce more rapid coastal erosion

what does prevailing winds cause in the uk?

prevailing winds come from the south-west and produce rapid coastal erosion in the south-west of the UK where there is weaker rock

what coasts do headlands and bays form on?

discordant coasts with bands of more and less resistant rock ordered in layers

how do headlands and bays form?

harder more resistant rock is not eroded and left standing as a headland whereas softer less resistant rock is eroded and the coast retreats forming a bay

why can’t headlands and bays form on concordant coasts?

since the same rock is exposed to the sea so the whole coast erodes at the same rate

how are cliffs formed

waves attack land by hydraulic action and abrasion between high and low tide levels

what does erosion between high and low tide marks cause?

a wave cut notch which eventually causes overhanging material to collapse under slumping or sliding

what is formed when a cliff’s overhanging material collapses?

wave cut platform which eventually gets eroded to form a rock pool and the debris is transported away

how are caves formed?

exposed headlands are attacked by destructive waves and joints are enlarged by hydraulic action which forms a cave

how are arches formed?

where the joint extends right through the headland, caves will form on both sides called an arch with a continous opening

how are stacks formed?

abrasion and hydraulic action continue to attack the sides of the arch between the low and high tidemarks creating a wave cut notch which then causes the overhanging material to collapse forming a stack

what are beaches

accumulations of sand/shingle found at the coast

where do beaches form

in areas of low energy constructive waves

why do beaches form in bays?

because the headlands shelter the bay from wind, reducing wave energy

what does the swash of destructive waves produce?

throws sand/shingle depositing material in backshore zone known as the storm beach

what does the swash of constructive waves produce?

a berm where the swash of the wave carries material up the beach but doesn’t have enough energy to carry it back down so it creates a ridge

what is a spit

a ridge of sand/shingle extending out into sea whilst connected by land

how are spits produced

by longshore drift on coastlines that change direction and extends the beach out into the sea

how does longshire drift carry material up in a zig-zag pattern

swash transports material up the beach at an angle and gravity pulls it back down perpendiculiarly

what is a bar

a ridge of sand/shingle stretching across a bay to land at both ends

how are bars formed

when longshore drift continues to deposit material up a spit

what do bars form

a lagoon

how has urbanisation affected coastal landscapes

-construction of millions of homes which involves reclaiming land by draining salt marshes

-weight of buildings can increase mass movement

-coastal defences build to protect settlements

How has agriculture affected coastal landscapes

-draining of salt marshes to create new farmland

--agricultural land does not have coastal defence as it isn’t worth it so physical landforms of the coast don’t change

how has industry affected coastal landscapes

-harbour construction and breakwater prevents longshore drift and deposition

-salt marshes may be drained for land

-industry may bring air and noise pollution

what are the 4 strategies of the shoreline management plan

no intervention, hold the line, advance the line, managed retreat

what is hard engineering

resists natural processes using artificial methods

what is soft engineering

works with natural processes and made from natural materials

what are sea walls

linear concrete structures built at the back of beaches

what are the advantages of sea walls

-prevents erosion and flooding

-may have a promenade for tourists

what are the disadvantages of sea walls

-very expensive to build and maintain

-visually unattractive

-may lead to beach erosion elsewhere

-makes it difficult to access the beach

what is the landscape impact of sea walls

-prevents coastal recession and maintains coastline

-halts cliff erosion

-introduces very visible human features

-may reduce sediment supply leading to increased erosion elsewhere

what are groynes

wooden or rock barriers interrupting longshore drift

what are the advantages of groynes

-creates/maintains beach for tourists

-beach absorbs wave energy and reduces erosion

-quick to construct and cheaper to build

what are the disadvantages of groynes

-difficult for people to walk along the beach

-increases erosion further down the coast

what is the landscape impact of groynes

-introduces very visible human features

-maintains position of coastline by preventing recession

-redues sediment supply leading to increased erosion elsewhere

what is rip rap

large boulders placed at the foot of a cliff or beach and absorb wave energy