Paper 1: Glaciation

• What is an ice age?

  An ice age is a period of colder global temperatures resulting in glacial expansion.
• How many ice ages have there been in the last 450,000 years?

  There have been 4 ice ages in the last 450,000 years.
• What is the average time span between ice ages?

  The average time span between ice ages is $100,000$ years.
• What was the extent of the ice sheet in the UK around 25,000 years ago?

  The majority of the UK was covered in ice, especially all of Scotland.
• Which regions of England were not covered in ice?

  The southern regions of England were not covered in ice.
• What is a glacier?

  A glacier is a large mass of ice that can form in highland areas.
• How do glaciers form?

  Glaciers form when snow accumulates and compresses into solid ice.
• What are the two main ways glaciers move?

  Glaciers move through basal flow and rotational slip.
• What is basal sliding?

  Basal sliding is influenced by gravity and involves a thin film of meltwater.
• What is rotational slip?

  Rotational slip occurs when glaciers move in a circular motion due to gravity.
• What are the key glacial processes?

  • Weathering
  • Erosion
  • Transportation
  • Deposition
• What is freeze-thaw weathering?

  Freeze-thaw weathering is the breakdown of rock due to freezing and thawing cycles.
• What is plucking in glacial erosion?

  Plucking is when meltwater freezes to bedrock and pulls out chunks of rock.
• What is abrasion in glacial erosion?

  Abrasion is when rocks frozen to the glacier scrape the bedrock like sandpaper.
• What is bulldozing in glacial transportation?

  Bulldozing is when rocks and debris are pushed downhill by the moving glacier.
• What is glacial till?

  Glacial till is the unsorted material deposited directly by a glacier.
• What is outwash in glacial deposition?

  Outwash is material deposited by meltwater streams from a glacier.
• What are the two types of glacial erosion?

  The two types of glacial erosion are plucking and abrasion.
• What is the difference between sorted and unsorted eroded rock from glacial deposition?

  Sorted rocks have a set pattern, while unsorted rocks vary in size.
• Why is smaller material found further away from the front of a glacier during outwash?

  Smaller material can be moved further due to less energy required.
• What are the characteristics of a corrie, pyramidal peak, and arete?

  • Corrie: A hollow with a steep back wall, often containing a tarn.
  • Pyramidal Peak: A sharp, pointed peak formed by glacial erosion.
  • Arete: A narrow ridge formed between two glaciers.
• How does a corrie form?

  A corrie forms when snow accumulates in a hollow, compresses, and moves due to gravity.
• What are the characteristics of a glacial trough and ribbon lake?

  • Glacial Trough: A U-shaped valley formed by glacial erosion.
  • Ribbon Lake: A long, narrow lake formed in a glacial trough after the glacier melts.
• How does a glacial trough form?

  A glacial trough forms when a glacier erodes a V-shaped valley into a U-shape through abrasion and plucking.
• How does a ribbon lake form?

  A ribbon lake forms when a glacier melts and leaves behind a long, narrow depression filled with water.
• What do glacial troughs and ribbon lakes look like on an OS map?

  Glacial troughs appear as U-shaped valleys, while ribbon lakes appear as long, narrow bodies of water.
• What are the key processes involved in glaciation?

  1. Accumulation of snow
  2. Compression into ice
  3. Movement of glaciers
  4. Erosion of landscapes
  5. Deposition of materials
• What causes a glacier to slip down a hill?

  Gravity and the downward motion of the glacier
• What is the process of abrasion in glacial movement?

  It causes rocks frozen to the base of the glacier to deepen the valley and scrape features
• What happens to a glacier after glaciation?

  The glacier melts and can infiltrate softer rock
• What is formed when a glacier melts and infiltrates softer rock?

  Long narrow ribbon lakes
• What are the three essential components to effectively answer a formation question?

  • A clear and full sequence of the formation
  • The processes that have occurred to form the feature
  • The correct geographical terms that relate to the feature
• What map evidence shows that Grisedale glacial trough has a flat bottom?

  No contour lines
• What are the features of glacial erosion?

  Truncated spurs, ribbon lakes, and pyramidal peaks
• How do glaciers move?

  By gravity and the processes of erosion
• What are the types of moraine?

  Lateral, medial, and terminal moraines
• How are lateral moraines formed?

  Through freeze/thaw weathering causing rocks to fall off a mountain side
• How are medial moraines formed?

  When two glaciers meet, their lateral moraines converge
• How are terminal moraines formed?

  Through bulldozing as the glacier reaches lower altitudes and melts
• What are drumlins?

  Egg-shaped mounds of till that show the direction of glacier movement