Topic 4 - The UK's Evolving Physical Landscape

Question 1

what are the 3 types of rock

Answer 1

igneous
sedimentary
metamorphic

Question 2

how are igneous rocks formed

Answer 2

when molten rock from the mantle cools and hardens. the rock forms crystals as it cools down. igneous rocks are usually hard

Question 3

how are sedimentary rocks formed

Answer 3

when layers of sendiment are compacted together until they become solid rock

Question 4

how are metamorphic rocks formed

Answer 4

when other rocks are changed by heat and pressure. the new rocks become harder and more compact

Question 5

what are the three main ways that techtonic activity has shaped the UK’s landscape

Answer 5

• active volcanoes
  -plate collisions
  -plate movements

Question 6

how have active volcanoes shaped the UK’s landscape

Answer 6

by forcing magma through the earth’s crust which has cooled to form igneous rocks

Question 7

how have plate collisions shapes the UK’s landscape?

Answer 7

plate collision causes the rocks to be folded and uplifted forming mountain ranges. many areas remain as uplands. the intense heat and pressure caused by plate collisions formed hard metamorphic rocks in northern Scotland and Ireland

Question 8

how have plate movements shaped the UK’s landscape?

Answer 8

plate movements meant that millions of years ago Britain was in the tropics and higher sea levels meant that it was partly underwater so carboniferous limestone formed in the warm shallow seas. the youngest rocks in the UK are chalks and clays found in southern England. they formed in shallow seas and swamps. chalks and clays are softer rocks and are more easily eroded they form lowland landscapes

Question 9

what are the characteristics of granite

Answer 9

• granite is very resistant and forms upland landscapes.
• it has lots of joints (cracks) which aren’t easily spread. the parts of the rock that have more joints wear down faster. areas that have fewer joined are worn down more slowly than the surrounding rock and stick out at the surface forming tors
• granite is impermeable - it doesnt let water through. this creates moorlands-large areas of waterlogged land and acidic soil with low growing vegetation

Question 10

what are the characteristics of carboniferous limestone

Answer 10

• rainwater slowly eats away at limestone through carbonation weathering. most weathering happens along joints in the rock creating some spectacular features.
• limestone is permeable so limestone areas also have dry valleys and resurgent rivers that pop out at the surface when limestone is on top of impermeable rock

Question 11

what are the characteristics of slate and schist

Answer 11

• slate forms in layers creating weak planes in the rock. it is generally very hard and resistant to weathering but is easily split into thin slabs
• schist has bigger crystals than slate and also splits easily into small flakes
• slate and schist often form rugged upland landscapes. they are impermeable which can lead to waterlogged and acidic soils

Question 12

what are the characteristics of chalk and clay

Answer 12

• chalk is harder than clay. it forms escarpments in UK lowlands and cliffs at the coast. one side of the hill is usually steep and the other side is more gentle
• chalk is permeable - water flows through it and emerges as a spring where it meets impermeable rock.
• clay is very soft and is easily eroded. it forms wide flat valleys in the UK lowlands. it is impermeable so water flows over the surface - there are lots of streams rivers and lakes

Question 13

what is weathering

Answer 13

the breakdown of rock into smaller pieces. it can be either mechanical chemical or biological

Question 14

what is erosion

Answer 14

the breakdown and removal of rock

Question 15

what are post glacial river processes

Answer 15

melting ice at the end of glacial periods made rivers much bigger than normal with more power to erode the landscape. the ice also leaves distinctive landforms when it is melted

Question 16

what are the 3 ways that humans have changed the landscape

Answer 16

-agriculture
- forestry
-settlement

Question 17

how have humans changed the landscape through agriculture

Answer 17

• humans have cleared the land of forest to make space for farming
• over time hedgerows and walls have been put in to mark out fields
• different landscapes are best for different types of farming
  1) arable - flat land with good soil
  2) dairy - warm and wet areas
  3) sheep - takes place in harsher conditions in the uplands as sheep are well suited to cold weather and steep slopes. sheep farming has lead to a lack of trees on the hills
• OS maps show the infleuence of agriculture incudin field boundaries and drainage ditches

Question 18

how have humans changed the landscape through forestry

Answer 18

• forestry is the management of areas of woodland they can be used for timber recreation or conservation
• the UK used to be covered in deciduous woodland but there is very little natural woodland left
• in some places deciduous woodland is being replanted to try to return the area to a more natural state
• OS maps show forestry plantations and areas that are being managed

Question 19

how are waves generated

Answer 19

waves are generated by wind blowing over the sea. Friction with the surface of the water causes ripples to grow into waves. the amount of energy in waves and therefore their ability to erode transport or deposit material along the coast depends on their height.

Question 20

what is swash

Answer 20

the water that surges up the beach until it runs out of energy

Question 21

what is backwash

Answer 21

the water that runs back down the beach under gravity

Question 22

what are destructive waves

Answer 22

waves formed by strong winds that have blown over long fetches. these waves are powerful and cause coastal erosion. destructive waves are tall and steep they are closely spaced and break frequently. the backwash is much stronger than the swash so rocks pebbles and sand are carried back out to sea. if beaches form they tend to be narrow and steep and offer cliffs little in the way of protection as the cannot absorb much of the wave energy

Question 23

what are constructive waves

Answer 23

waves that are associated with light winds and short fetches. the waves have less energy and encourage deposition. they are low in height and widely spaced breaking gently. the swash is stronger than the backwash so more material is carried up the beach than is removed. the resulting beaches tend to be wide and shallow and they help to protect the cliffs from erosion as the wave energy is absorbed by the beach

Question 24

what is a discordant coast

Answer 24

coasts with bands of resistant and less resistant rocks running at right angles to the coastline.

Question 25

what is a concordant coast

Answer 25

coasts with bands of resistant and less resistant rocks running parallel to the coastline

Question 26

how are headlands and bays created

Answer 26

the cliffs along a discordant coast erode at varying rates as rocks of different hardness and resistance meet the sea. the stronger or harder rocks such chalk are able to resist wave attacks and erosion for longer these sections of cliff stand out as prominent and rocky headlands. the softer weaker rocks such as mudstones and siltstones are eroded back more quickly to form bays

Question 27

what are the four types of erosion

Answer 27

-attrition
- abrasion
- hydraulic action
- solution

Question 28

what is attrition

Answer 28

when pieces of rock material are moved by waves and knock into each other. when this happens any corners sticking out get knocked off. the material gets smaller and rounder eventually turning into sand

Question 29

what is abrasion

Answer 29

takes place on cliffs when waves pick up sand and pebbles and throw and scrape them against the rock surface. this wears away the rock in an action similar to sandpaper on wood

Question 30

what is hydraulic action

Answer 30

when large waves break against a cliff. when this happens they compress air into the cracks. when the water falls away the compressed air is suddenly released explosively shattering the rock

Question 31

what happens when headlands erode

Answer 31

• when waves crash into the headlands they enlarge the cracks mainly by hydraulic action and abrasion
• repeated erosion and enlargement of the cracks causes a cave to form
• the erosion deepens the cave until it breaks through the headland forming an arch
• the erosion continues to wear away the rock supporting the arch until it collapses
• this forms a stack - an isolated rock that is separate from the headland

Question 32

what is longshore drift

Answer 32

when waves following the direction of the prevailing wind hit the coast at an angle. the swash carries the material u the beach in the same direction as the waves and the backwash carries the material down the beach at right angles.