Uks evolving physical landscape Flashcards
(35 cards)
Granite
Upland areas
Very resistant
has joints that are unevenly spread
more joints ,the more weathering
impermeable
Slate and schsits
forms in layers creating weak planes in the rock
very hard and resistant to weathering easily split into slabs
impermeable leading to acidic soil
Carboniferous limestone
Rainwater eats away at the limestone through carbonation weathering
most of weathering happens at joins creating spectacular features
limestone is peremable
Chalk
Chalk is harder than clay and form hills at in lowland
cliffs at coast
chalk is permeable and forms springs where it meets impermeable rock
Clay
Soft and easily eroded
forms wide flat valleys in lowlands
impermebale
uk covered in ice
Uk went through many glacial periods
uk was coverered in massive sheets of ice
ice eroded landscapes carving u-shapped valleys
glaciers metled and deposited materials
What are the four physical processes that altered the landscape ?
Weathering
Erosion
post-glacial period
slope process
Weathering
the breakdown of rock
chemical ,mechanical,physical
Erosion
The wearing away of rocks
Post -glacial processes
3 ways
melting ice made rivers much bigger
rivers had more power to erode the landscape
melting ice created distinctive landscapes
slope processes
Mass movements-rockfalls ,slides ,slumps
What are physical processes affected by
Climate
Which are the three ways that humans have changed lanscapes ?
Agriculture
foresty
Settlement
Agriculture
arable
Dairy
sheep
humans have cleared landscape for farming
arable-flat land with good soil
Dairy -Warm and wet areas ,large grassy fields
sheep -harsher conditions in uplands
What do OS maps show ?
influence of agriculture ,show field lines,show drainage ditches
What is forestry
what can woodlands be used for ?
management of woodland areas
can be used for conservation,timber,recreation
was covered in deciduous landscape ,not a lot left
coniferous trees are being planted for timber
in some areas deciduous woodland is being replanted
Settlement
earky steelers
Early settlers -needed a water supply +somewhere that could be defended easily +sheltered from wind and rain
bridging points and availability of other resources
As settlements grew how did they further influence landscape ?
3 ways
the land was concreted affecting drainage patterns
rivers were diverted through underground channels
some rivers were straightened or had embankments built to prevent it from flooding
What is mechanical weathering ?
give main example
explain how it works
breakdown of rock without changing its chemical composition
Salt weathering
sea water gets into cracks
when water evaporates it forms crystals of salt
salt crystals form they expand putting pressure on the rock
repeated evaporation widens the cracks and causes the rock to break up
What is chemical weathering?
What is teh main example
The breakdown of rock whilst changing the chemical composition
Carbonating weathering -Seawater and rain have co2
dissolved in them making them weak carbonic acids .
carbonic acids react with calcium carbonate
What is biological weathering ?
breakdown of rock by living things
plant roots break down rocks by growing in the cracks and pushing them apart
What is mass movement?
Why does this happen (gravity)
What does mass movement cause
when are they more likely to happen
examples of mass movements ?
shifting of rocks and loose materials down a slope
the force of gravity is greater than the force supporting it
mass movements cause coasts to retreat rapidly
They’re more , likely to happen when material is full of water therefore the material is heavier
slides ,slumps and rockfalls
attrition
when pebbles in the river knock against each other ,they get smaller and more rounded
abrasion
When pebbles grind along the river bank and bed