Glaciation

Question 1

what are glaciers

Answer 1

large ‘rivers’ of ice

Question 2

how do glaciers form

Answer 2

Glaciers are formed in high land when the climate is cooler and most of the precipitation falls as snow.
The snow accumulates and over time is compressed into ice.
When the glacier is large enough it will move downhill under its own weight and the force of gravity.

Question 3

What was the Pleistocene?

Answer 3

the last ice age

Question 4

When did the Pleistocene occur?

Answer 4

between 11,800 and 2.58 million years ago

Question 5

Name some of the areas of Europe affected by glaciers during the Pleistocene

Answer 5

scotland, england, denmark, belgium, germany

Question 6

explain, in detail, the process of freeze-thaw.

Answer 6

water seeps into gaps into rocks and when the temperature drops the water expands as it freezes, this applies pressure to the rock this process repeats and repeats until the rock is so weak that it breaks apart

Question 7

What other terms are used to describe freeze-thaw

Answer 7

Frost shattering, nivation

Question 8

how does plucking occur

Answer 8

Plucking occurs along the base and sides of the glacier
Glaciers freeze onto rock surfaces
When they begin to move downhill under their on weight and the force of gravity, they tear pieces of rock away with them

Question 9

how does abrasion occur

Answer 9

Abrasion also occurs along the base and sides of the glacier.
It is the sandpapering effect of the glacier and the rocks frozen to its base.
When the glacier travels along the land, the rocks frozen to its base scrape away at the land underneath.

Question 10

what is a corrie

Answer 10

A corrie is a bowl shaped hollow on a mountainside.

Question 11

how does a corrie form

Answer 11

At the beginning of the ice-age the temperature dropped
Snow collected in north-facing hollows on mountainsides, where conditions were cooler.
As layer upon layer of snow was laid down, it was compressed into ice
Under its own weight and the force of gravity, the glacier began to move downhill in a rotational fashion.
As it did so it plucked rock away, steepening the back wall of the hollow.
Meanwhile, abrasion deepened the hollow where the glacier was thickest and heaviest.
The glacier lost strength as it moved up and out of the hollow. This left behind a notch of rock at the entrance of the hollow, called a rock lip.
Loose rock, soil, gravel and clay was bulldozed forward at the snout of the glacier (the front of the glacier).
This formed a terminal moraine at the entrance to the corrie.
At the end of the ice-age the glacier melted
The terminal moraine sealed in the meltwater to form a corrie loch called a tarn

Question 12

what is an arete

Answer 12

Arêtes are knife-edged ridges.

Question 13

how does an arete form

Answer 13

They are formed when two corries adjacent to each other erode back into the mountain.
This narrows the area of land between them.
When describing or explaining how arêtes form, you must first describe or explain the formation of a corrie

Question 14

what is a pyramidal peak

Answer 14

Pyramidal peaks form where three or more corrie glaciers erode back to back on a mountainside.

Question 15

how does a pyramidal peak form

Answer 15

When the corrie glaciers erode their backwalls, they create arêtes. They also narrow the peak between each corrie.
This forms a mountain peak that is roughly pyramidal in shape.
Where glaciers are unable to cover the peak, nivation sharpens this. This will continue after the ice-age. It enhances the pyramidal shape.

Question 16

how do U-Shaped valleys form

Answer 16

At the beginning of the ice-age precipitation fell as snow.
This collected and was compressed together to form crystallised snow called firn or néve. Further compression turned it into ice.
Under its own weight and the force of gravity the glacier began to make it way downhill through a pre-existing V-shaped valley.
Freeze-thaw weathering weakened the rocks in the area. Water seeped in to cracks and fissures in the rock. During cold weather it froze and expanded putting pressure on the rock. It then thawed and the rock contracted slightly. The process happened over and over again, until the rock was so weakened it broke apart.
The glacier froze to the valley sides and then as it began to move again it plucked pieces of rock away from the sides.
Rocks frozen to the sides of the glacier also scraped away at the land.
This helped to truncate (cut-off) the interlocking spurs, thus steepening the valley sides, widening the valley and straightening it out.
Plucking and abrasion also occurred along the valley floor. Abrasion was greatest where the glacier was heaviest. This helped to deepen the valley.

Question 17

how does a ribbon lake form

Answer 17

In some areas on the floor of U-shaped valleys, the rock may be weaker.
At those points glaciers were able to erode more deeply. They were also able to erode more deeply where glaciers were thicker and heavier.
This created elongated hollows along the floor of the valley.
When the glaciers melted those hollows filled with the meltwater to form lakes.
The meltwater was sealed in by terminal moraine.
Glaciers plucked and abraded materials such as sand, clays, boulders and gravel as they travelled. They then carried this material along with them. Where it was bulldozed forward at the snout of the glacier and then left as a ridge across the entrance to a U-shaped valley, it formed a terminal moraine.
As the hollows were typically long and thin in shape, the lakes are referred to as ribbon lakes

Question 18

how do hanging valleys form

Answer 18

Hanging valleys were formed where a smaller tributary glacier formed above the main valley glacier.
Those smaller glaciers were not able to erode to the same width and depth as the main valley glacier.
They therefore formed a smaller glacier that hangs above the main valley glacier.
NB: When describing and/or explaining the formation of a hanging valley, you must first describe and/or explain the formation of a U-shaped valley.

Question 19

how does a truncated spur form

Answer 19

Truncated spurs are the flat, steep valley sides of a u-shaped valley.
Before the ice-age valleys were narrow river V-shaped valleys with rounded, gently sloping hills.
The foot of the hills formed interlocking spurs (areas of land that jutted out and that the river wound round because it did not have the erosive power to remove them).
During the ice-age glaciers eroded those interlocking spurs.
At times the glacier would freeze onto the spurs and then as it started to move downhill would pluck pieces of rock away.
Abrasion occurred where rocks frozen to the base and sides of the glacier scraped away at the interlocking spurs in a sandpapering motion.
As a result of this the ends were removed from the interlocking spurs, truncating them.
This gave the sides of the U-shaped valley a steep, flat sided appearance.
Where erosion was greatest, crags and cliffs formed.

Question 20

explain why glaciated uplands are ideal places for water storage and supply.

Answer 20

Upland glaciated areas often have relief rainfall that provides plenty of surface drainage (rivers, streams and lakes).
The ribbon lakes that form in U-shaped valleys are natural reservoirs that store vast quantities of water.
Rivers and lakes can be dammed. This allows water to collect behind the dam, creating artificial lakes where a river has been dammed or allowing more water to collect in natural lakes.
This water can be used to provide a water source for housing, industry, services, etc. in nearby towns and cities.

Question 21

explain why glaciated uplands are ideal places to generate renewable energy.

Answer 21

Steep slopes pull water downhill rapidly under the force of gravity. This can generate electricity in hydroelectric power stations.
High exposed areas get plenty of strong wind. This makes them ideal sites for wind farms.

Question 22

Explain, in detail, three advantages (positive impacts) and three disadvantages (negative impacts) of water storage and supply in glaciated uplands.

Answer 22

Dams built over rivers to create lochs for water supply and HEP that will flood vast areas. This will have obvious negative impacts on wildlife habitats e.g. nesting sites for birds.
Dams reduce the flow of water downstream and this can affect insect species that lay their eggs in water. This can in turn affect fish and other animals that feed on the insect eggs and larvae.
Dams can affect the migration of fish, such as salmon, reducing numbers as the fish cannot reach their breeding sites.
Dams provide essential water supplies and energy for nearby towns and cities. This allows industrial development, increasing employment. During construction the dams also provide employment opportunities. Wind farms also provide energy. Both HEP and wind energy are clean and renewable.

Question 23

Explain, in detail, three disadvantages (positive impacts) and three disadvantages (negative impacts) of renewable energy in glaciated uplands.

Answer 23

Wind farms have been known to kill birds. Many endangered raptors such as red kites and eagles live in those upland areas. Wildfowl often fly over those areas when they migrate south for the winter. They can fly in to the turbines at times of poor visibility this kills them.
The noise and flickering effect given off by wind turbines has been proven to affect peoples health. This could impact on people living close to the turbines.
People living in areas where there are HEP stations and wind farms can be provided with cheaper power supplies.

Question 24

Explain, in detail, three advantages (positive impacts) and three disadvantages (negative impacts) of forestry in glaciated uplands.

Answer 24

Uniform blocks of forestry containing the same species of trees can look unnatural and unattractive.
Planting forestry, especially non-native species can affect natural habitats in an area.
The trees absorb carbon dioxide from the atmosphere as they grow. This helps to counteract the effects of global warming.
Areas re-planted with native species can improve natural habitats.
The forestry can stabilise slopes, preventing landslides. The tree roots hold the rock and soil in place. The trees themselves absorb and intercept rainwater that can often cause landslides.

Question 25

In your own words, explain why glaciated uplands are ideal places for tourism.

Answer 25

Glaciated uplands are usually very scenic areas, with the mixture of lakes and mountains.
The varied topography provides gentle walking on the flat U-shaped valley floors. Steeper slopes provide challenging hill walks. Rock outcrops provide opportunities for rock climbing. North-facing hollows in high altitude, high latitude areas can provide skiing (look for ski tows on the map).
The varied topography also lends itself to mountain biking with steeper areas providing challenging runs and gentler tracks along valley floors providing routes for less experienced mountain bikers.

Question 26

Explain, in detail, three advantages (positive impacts) and three disadvantages (negative impacts) of tourism in upland glaciated areas.

Answer 26

Tourists trample over farmland when trying to access areas e.g. hills. This can erode grazing land and crops. They may damage field boundaries e.g. drystone walls by climbing over those to access areas.
Tourists may allow dogs off of leads. Dogs can worry pregnant ewes, causing them to miscarry. They can also kill sheep and lambs. This affects the farmers income. Farmers have the right to shoot any dog that is out of control on their land.
Tourists drop litter. Livestock can eat this and become ill, which can lead to costly vet bills for farmers. Wildlife can also ingest litter which can lead to death.
Tourists bring much needed employment and income in to upland glaciated areas which have traditionally suffered from rural depopulation, due to the lack of job opportunities.
Tourist spending creates a multiplier effect. Hotels, shops and services open up due to increasing tourism. Those hotels, shops and services provide jobs for local people. This boosts employment and the disposable income that people now have. Other shops and services open up to take advantage of the increasing disposable income that local people now have. Those employ more people and so it goes on. The multiplier effect can improve the services and shops in some areas.

Question 27

In your own words, explain why glaciated uplands are ideal places for hill-sheep farming

Answer 27

Sheep are sure-footed and can therefore cope with the steep terrain.
Sheep have a thick waterproof fleece and so can survive the cold temperatures and high rainfall found at high altitudes.
Sheep can survive on the poor quality vegetation that grows on the thin stony soils.
The land is not suitable for other types of farming, for example arable farming that requires large machinery that cannot be used on steep land. The quality of the grazing is not good enough for dairy cattle.

Question 28

Explain, in detail three advantages (positive impacts) and three disadvantages (negative impacts) of hill-sheep farming in glaciated uplands.

Answer 28

Sheep can also eat plants down to their roots. This reduces the vegetation cover, which if left would absorb some of the rainwater. The plant roots also bind the soil together, preventing it from moving downslope.
Although sheep release less methane than cattle, they still release a considerable amount, causing further climate change.
Hill-sheep farming is an important traditional industry. It employs farmers and seasonal workers required during shearing and lambing.
Sheep compact the slopes, preventing infiltration of rainwater. Instead the rainwater flows straight over the land, eroding away the rock and soil as it does so.
The presence of sheep on slopes can destabilise them, leading to landslides and rock falls,

Question 29

In your own words, explain, in detail, why glaciated upland areas are ideal for the quarrying and mining industry.

Answer 29

There is a plentiful supply of exposed rock. The thin soils and poor vegetation cover mean that it is easy to clear those areas to access the rock underneath.
The rock in glaciated uplands is older sedimentary (e.g. limestone), igneous (e.g. granite) and metamorphic rocks (e.g. slate). Those rocks are hard wearing and are therefore ideal for the construction of roads and buildings.

Question 30

Explain, in detail three advantages (positive impacts) and three disadvantages (negative impacts) of quarrying and mining in glaciated uplands.

Answer 30

Quarries are unsightly scars on the landscape that destroy the beautiful scenery of those areas. Once quarried an area cannot be returned to its natural state as large portions of rock have been removed from that landscape.
The noise created by blasting and quarry equipment, e.g. diggers destroys the peace and tranquility that many people expect when they visit those areas.
Large quarry trucks can block up narrow roads, where they pass each other. They can also be intimidating for tourists.
In the Lake District quarrying is a traditional industry. Generations of families have worked in those quarries and rely on the income generated.
The quarried stone is required to preserve the traditional farming a village landscapes. The rock is used to maintain drystone walls around fields. It is also used to maintain the older traditional buildings and to allow the construction of new buildings in the traditional style. This helps to retain the quaint appearance of the Lake District’s towns and villages.
It provides many jobs for lorry and truck drivers in the area to transport the stone