Glaciation revision

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Glaciation revision
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Key points

• At all three levels (foundation, general and
  credit) you have to be able to recognise the main
  features, and be able to describe and explain
  their formation. You must fully understand the
  term natural process

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Map work - what you should know

• On a landscape diagram or OS map be able to
  identify
• Corries , pyramidal peaks and aretes
• Corrie lochs/lakes/tarns
• Hanging valley
• U-shape valley
• Truncated spurs
• As well as features formed by ice sheets
• depositing materials i.e. moraines, outwash
  plain,
• eskers, drumlins and erratics

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Formation processes

• Glacial erosion occurs through two processes,
  abrasion (sandpapering effect as ice moves across
  the land) and plucking (pieces of rock being torn
  away from the land)
• Abrasion tends to lead to smoothed surfaces while
  plucking tends to produce jagged features
• The glaciers consist of ice in which melting ice
  near the base of the glacier causes a process
  known as internal deformation.

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• The weight of the glacier causes it to slide on
  top of the melting ice. Called basal sliding. How
  fast the glacier flows depends on the type of
  rock it is on , the amount of ice in the glacier
  and the slope of the land. The process of melting
  is called ablation

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• As glaciers move they erode and deposit material
  at their margins - that is, at the front and
  sides. Melt waters flowing from the glaciers
  further erode and deposit material in a process
  known as fluvioglacial process

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Formation of a corrie

1. Snow collects in hollow high in the mountains
2. Snow compacts to form ice
3. Weight of ice causes it to move, helped by
   melting water underneath
4. Ice has rotational movement to lip of hollow
5. Plucking and abrasion by the ice deepens the
   hollow, this is also how steep back wall is
   produced
6. After the ice has melted a corrie loch may form
7. 2 corries back to back steep ridge Arete
8. 3corries around a mountain top Pyramidal peak

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Formation of a U-shaped valley

• Glacier flows down an existing V shaped valley
• Glacier erodes sides and floor of river valley
• The valley widens, deepens and straightens
• After the glacier the valley is U shaped
• Valley has very steep sides wide flat floor with
  a misfit stream
• If the question says you may use a diagram USE
• ONE! it will be hard to get full marks without
  one.
• If it says with the aid of a diagramUSE ONE!
  it is
• IMPOSSIBLE to get full marks without one

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Land use of glacial uplands

• Tourism - sightseeing, hill walking etc e.g.
  Cairngorms
• Winter sports - Ski resorts e.g. Aviemore
• Hydro-electric power - high rainfallsupply,
  Corrie lochs provide storage, steep slopes fast
  flowing water e.g. Ben Cruchan
• Settlements/mountain passes - Flat valley floor
  good for settlements and and roads, railway lines
  through mountains
• Terminals for large tankers - Fiords and sea
  locks e.g. Finnart on Loch long
• What conflicts can these different uses create?

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Exam style question

• There is a plan to plant trees on area X name a
  group that might be against the plan and give
  reasons why (3ES)

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Lowland features

• Moraine - name for material carried by glacier,
  can be terminal, lateral, surface or ground
• Boulder clay/till - soil formed under the glacier
• Outwash plain area of sands and gravels found
  beyond terminal moraine
• Esker - long ridges of moraine marking path of a
  river under the glacier
• Drumlins - long rounded hill with steeper
  upstream side

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Land use glacial lowlands

• Farming - fertile soil caused by glacial boulder
  clay (note stones and gravel NOT fertile)
• Quarrying - sands and gravel
• Settlement - farms, villages, towns

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What features can you see here? What about land
uses? What would be the pros and cons of a new
sport/ outdoor centre at