UK Physical Flashcards
How have active volcanoes helped to shape the UK landscape?
520m years ago, the UK used to be closer to plate boundaries. Active volcanoes forced magma through these boundaries and the magma cooled to form igneous rock e.g. granite
How have plate collisions helped to shape the UK landscape?
- Plate collisions caused rocks to be folded and uplifted forming mountain ranges.
- Many of these remain as the Scottish highlands or the lake district as the igneous rock is more resistant to erosion
- The intense heat caused by plate collisions formed hard metamorphic rocks in Scotland and Northern Ireland
How has plate movement helped to shape UK landscape?
- The UK used to be in the tropics 245-280m years ago meaning that carboniferous limestone would form. This can still be seen in upland areas like the peak district and south Wales and south West England
- Chalks and clays formed in Southern England most recently
What are the characteristics of granite?
- Very resistant
- Forms upland landscapes
- Has joints(cracks) that are unevenly spread which erode faster, forming tors
- Impermeable which forms moorlands
- An igneous rock
What are the characteristics of carboniferous limestone?
- Rainwater erodes the limestone through carbonation weathering creating limestone pavements, caverns and gorges
- Limestone is permeable forming dry valleys and resurgent rivers if limestone is on-top of permeable rock
- Sedimentary rock
What are the characteristics of slate and schist?
- Slate forms in layers creating weak planes in the rock. Very hard and resistant to weathering but is easily split into thin slabs
- Schist has bigger crystals than slate and splits easily into small flakes
- Both form rugged upland landscapes and both are impermeable creating waterlogged and acidic soils
- Metamorphic rocks
What are the characteristics of chalk and clay?
- Chalk is harder than clay and forms escarpments (hills) in lowlands and cliffs at the coast
- Chalk is permeable and water forms a spring when it meets impermeable rock
- Clay is soft and easily eroded. Forms wide flat valleys. Impermeable
- Both sedimentary rocks
How has glaciation helped to form UK landscapes?
- Glaciers eroded U-shaped valleys in upland areas like the lake district
- Glaciers deposited material as they melted e.g. large parts of Eastern England are covered in till deposited by the melting glaciers
How does mechanical weathering (salt weathering) erode coastlines?
- Seawater gets into cracks in the rocks
- When the water evaporates salt crystals form which expand and put pressure on the rocks
- This process repeated widens the cracks and causes the rock to break up
How does chemical weathering (carbonation weathering) erode coastlines?
- Carbon dioxide dissolved in seawater and rainwater makes them weak carbonic acids
- These weak acids react with rocks that contain calcium carbonate causing them to dissolve
How does biological weathering erode coasts?
-Plants grown into cracks in the surface of rocks, causing them to be pushed apart, breaking them down
What are the three processes of wave erosion and what are their characteristics?
Hydraulic action:
Waves crash into rocks and compress the air in the cracks. This puts pressure on the rock until eventually the cracks are widened enough for bits to break off
Abrasion:
Eroded particles in the water scrape and rub against the rock, removing small pieces
Attrition:
Eroded particles in the water smash into each other, breaking into smaller fragments and causing them to be rounded
What is mass movement and what are the three types?
The shifting of rocks and loose materials down a slope that happens when the force of gravity acting on a slope is greater than that of the force supporting it
The three main types are:
- Slides
- Slumping
- Rockfalls
What are the characteristics of destructive waves?
- High, steep and high frequency (10-14 waves per minute)
- Their backwash is more powerful than their swash
What are the characteristics of constructive waves?
- Low, long and low frequency (6-8 per minute)
- The swash is stronger than the backwash and so they deposit material
How are spits formed?
- They form at sharp bends in the coastline
- LSD transports sand and shingle past the the bend and deposits it in the sea
- Strong winds can cause the the end of the spit to curve, forming a recurved end
- The area behind this is protected from waves and so material accumulates there forming a mud flat or a salt marsh
How are bars formed?
- When a spit joins two headlands together
- The bar cuts off the the bay between the from the sea
- This can result in a lagoon forming behind the bar
How can landforms caused by erosion and deposition be seen on maps?
Caves: -Can't be seen Stacks: -Little blobs in the sea Cliffs: -Shown as little black lines Wave-cut platforms: -Shown as bumpy edges along the coast
Sand beaches: -Shown on maps as pale yellow Shingle beaches: -Shown as whit/yellow with speckles Spits: -Shown by a beach that carries on out to sea but is still connected to land at one other end