Glacial Landscapes in the UK Flashcards
All 52 cards in this deck
True or false? Ice covered the whole of the British Isles at the maximum extent of the last ice age.
False. At its maximum the ice reached only about as far south as South Wales and the Midlands; southern England stayed ice-free.
What is abrasion?
Rocks trapped beneath the glacier scratch and smooth the bedrock underneath, leaving striations.
What is plucking?
Rocks freeze into the base and sides of the glacier, and as the ice moves it tears them away from the ground.
What are the steps of freeze-thaw weathering?
e.g. a crack in exposed rock above a glacier- By day snow melts and water enters the crack — the crack fills with water.
- Temperature falls below 0°C, the water freezes and expands by about 9% — the crack is widened.
- The process repeats — pieces of rock break off and fall onto the glacier.
What is bulldozing by a glacier?
Rocks and debris in front of the glacier are pushed downhill by the sheer force of the moving ice.
What is rotational slip?
The movement of ice in a circular motion within a hollow, deepening the hollow to form a corrie.
What is the difference between till and outwash?
Till is dropped directly by the ice and is angular and unsorted; outwash is carried out by meltwater streams and is sorted into different sizes.
Why is material deposited by a glacier mixed in size and shape?
Ice is solid, so it carries everything from fine debris to large boulders and bulldozes all material in its path.
True or false? A glacier deposits its load mainly because the ice is melting.
True. As the ice melts it can no longer carry its load, so debris is dropped.
What is a corrie?
An armchair-shaped hollow high on a mountainside with a steep back wall and a rock lip; it may contain a tarn.
True or false? In the UK, corries most often face south.
False. They usually face north or north-east, where there is least direct sunshine so snow can build up.
What is an arête?
A narrow, knife-edge ridge formed where two corries erode back to back.
What is a pyramidal peak?
A sharp-pointed mountain summit formed where three or more corries erode back into the same mountain.
What is a truncated spur?
A former interlocking spur of a river valley that has been cut off and steepened by the glacier moving straight down the valley.
What are the characteristics of a glacial trough (U-shaped valley)?
Steep sides, a wide flat valley floor and a U-shaped cross profile.
What is a ribbon lake?
A long, relatively narrow lake occupying a glacial trough, where the ice eroded a deeper hollow in the valley floor.
What is a hanging valley?
A shallow tributary valley left high above the floor of the main glacial trough; a river in it plunges as a waterfall.
What is an erratic?
A large boulder transported and deposited by a glacier in an area of different rock type.
How does the shape of a drumlin show the direction the ice was moving?
The blunt, steeper end faces up-ice (where the ice came from) and the long axis tapers to a pointed end down-ice.
What is a terminal moraine?
A high ridge of unsorted material across the valley, marking the maximum extent reached by the glacier snout.
What is a lateral moraine?
A ridge of unsorted debris along the valley side, formed from frost-shattered rock falling onto the edge of the glacier.
What is a medial moraine?
A ridge of debris down the middle of the valley, formed where the lateral moraines of two glaciers merged.
What is ground moraine?
Material carried at the bottom of the glacier that is left spread over the valley floor when the ice melts.
True or false? On an outwash plain the finest sediment is deposited closest to the glacier snout.
False. The coarsest material is dropped nearest the snout; meltwater carries the finest sediment furthest away.
Give two pieces of evidence on a map or photograph that an upland area was glaciated.
Any two: a long narrow ribbon lake; a steep-sided glacial trough; a flat valley floor; moraine/till deposits.
Name the four main economic activities in glaciated upland areas.
Tourism, farming, forestry and quarrying.
Why are economic opportunities limited in glaciated upland areas?
Steep slopes, thin soils, low temperatures and heavy relief rainfall make it hard to earn a living from the land.
What is the main type of farming on glaciated uplands, and why?
Sheep grazing — soils are thin and acidic, and sheep tolerate cold, wet, windy conditions and poor vegetation.
Why is coniferous forestry suited to glaciated upland areas?
Conifers cope with acidic soils and steep slopes, and their softwood is used for construction timber and paper.
Why is quarrying common in glaciated upland areas?
They are made of hard, resistant rock (e.g. slate, granite, limestone) that is crushed for construction and road building.
Give one conflict between tourism and conservation in a glaciated upland area.
Visitors cause footpath erosion, traffic congestion, noise and air pollution, which damage the habitats conservationists want to protect.
Give one conflict between quarrying and conservation in a glaciated upland area.
Quarrying brings noise, dust and heavy traffic that destroy habitats and reduce biodiversity, and the quarry is an eyesore that can deter tourists.
Give one conflict between farming or forestry and conservation in a glaciated upland area.
Clearing land and logging can destroy natural habitats and reduce biodiversity, even though they provide rural jobs.
Give one argument that development in a glaciated upland area can help conservation.
Money brought in by activities such as tourism can be invested in conservation projects and sustainable management.
Give two attractions of a UK glaciated upland area for tourists.
Mountains and glacial landforms for walking, climbing and mountain biking; glacial lakes for scenery and water sports.
Give one economic impact of tourism in a UK glaciated upland area.
It creates jobs in hotels, shops, cafés and outdoor activities, though much of the work is seasonal and low paid.
Give one social impact of tourism in a UK glaciated upland area.
Holiday and second homes push house prices up, so local people on low wages cannot afford to buy.
Give one environmental impact of tourism in a UK glaciated upland area.
Footpath erosion — walkers destroy vegetation and exposed soil is washed away, leaving large erosion scars.
Give two strategies used to manage footpath erosion in a glaciated upland tourist area.
Resurfacing paths with hard-wearing material (stone, slabs, mesh); reseeding eroded ground; signposting or fencing alternative routes.
Give one strategy used to manage traffic congestion caused by tourism in a glaciated upland area.
Provide and encourage public transport in the tourist season, e.g. extra bus services or park-and-ride, so fewer visitors drive in.
True or false? Plucking and abrasion are processes of weathering.
False. They are processes of glacial erosion; freeze-thaw is the main weathering process.
True or false? Drumlins are landforms of glacial erosion.
False. They are depositional landforms, made of till deposited beneath the glacier and then shaped by moving ice.
Give one conflict between tourism and farming in a glaciated upland area.
Visitors may leave field gates open so livestock stray, let dogs worry sheep, or knock down dry-stone walls, so some farmers try to discourage walkers from crossing their land.
Why do some conservationists object to sheep grazing in glaciated upland areas?
Sheep eat young plants and saplings, so trees and shrubs cannot regrow and the land stays as open grassland or moorland; fencing sheep out lets natural vegetation return.
How can water sports on a glacial lake harm the environment?
Jet skis and powerboats are noisy and disturb wildlife, waves from the boats wear away the lakeshore, and fuel leaking into the lake pollutes the water.
Why can holiday homes reduce services for local people in a glaciated upland tourist area?
Many holiday homes are empty for much of the year, so fewer people live there all year round to support local shops, schools and public transport, and some of these close or are cut back.
Roughly how long ago did ice reach its maximum extent across the UK in the last ice age?
About 20,000 years ago.
True or false? Glaciers are still found in the UK's highest uplands today.
False. The UK has no glaciers today; its glacial landforms were made by ice that has since melted. Some snow patches in the Scottish Highlands can survive through summer, but they are not glaciers.
How is the flat floor of a glacial trough often used for farming?
For grazing cattle and growing grass to cut for hay or silage as winter feed; the climate is usually too cold and wet for arable crops.
How does a corrie appear on an OS map?
Very closely spaced contours curving round in a horseshoe shape around a hollow with a flatter floor, open on its downhill side; the hollow may hold a small lake (tarn).
How does an arête appear on an OS map?
A long, very narrow ridge: closely spaced contours run along its length on both sides, showing steep slopes falling away each side, usually into corries.
How does a glacial trough appear on an OS map?
A broad valley whose flat floor is crossed by few or no contours, with closely spaced contours up both steep sides; it is often fairly straight and may hold a ribbon lake or a small (misfit) river.