2.3.2

Glacial Movement

Test yourself

Factors Affecting Movement

Glaciers move by a range of different processes and at different rates. A range of factors influence rates of glacial movement.

Illustrative background for AltitudeIllustrative background for Altitude ?? "content

Altitude

  • The potential energy gained from height can increase glacier movement.
  • But, high-altitude glaciers are more likely to be cold-based for longer time periods in a year so won't move as much.
Illustrative background for Slope and lithologyIllustrative background for Slope and lithology ?? "content

Slope and lithology

  • Steeper sloped valley glaciers have higher rates of flow.
  • Lithology influences bed topography. Easily eroded rocks (e.g. sandstone) are more likely to eroded, creating deformations which may slow movement down.
Illustrative background for Mass balanceIllustrative background for Mass balance ?? "content

Mass balance

  • Areas of accumulation have slower rates of movement than areas of ablation.

Types of Glacial Movement

Glaciers move by a range of different processes and at different rates.

Illustrative background for Basal slipIllustrative background for Basal slip ?? "content

Basal slip

  • Basal slip is linked to the pressure melting of ice that takes place along its base.
  • Ice normally forms from water at a temperature of 0oC, but the temperature at which water freezes is reduced under pressure.
  • As a glacier moves it will exert pressure and so some melting may take place at its base.
  • A thin film of water then exists between the glacier and the bedrock.
  • This film reduces friction, acts as a lubricant, and allows the glacier to slide.
Illustrative background for Regelation creepIllustrative background for Regelation creep ?? "content

Regelation creep

  • Regelation is the re-freezing of water under a glacier when pressure reduces after meeting an obstruction.
  • Pressure melting takes place on the upstream side, creating a film of water, and regelation takes place on the downstream side.
  • The combination of both processes allows a temperate glacier to slide downhill.
Illustrative background for Internal deformationIllustrative background for Internal deformation ?? "content

Internal deformation

  • Internal deformation is small in scale and takes place in all glaciers, but it is the most common form of movement in cold-based glaciers.
  • It takes place where the ice crystals set themselves in line with the movement of the glacier and slide past each other.
  • Movement can occur along lines of weakness called cleavage planes . This is sometimes called laminar flow.

Jump to other topics

1Tectonic Processes & Hazards

2Option 2A: Glaciated Landscapes & Change

3Option 2B: Coastal Landscapes & Change

4Globalisation

5Option 4A: Regenerating Places

6Option 4B: Diverse Places

7The Water Cycle & Water Insecurity (A2 only)

8The Carbon Cycle & Energy Security (A2 only)

9Superpowers (A2 only)

10Option 8A: Health & Human Rights (A2 only)

11Option 8B: Migration & Identity (A2 only)

Go student ad image

Unlock your full potential with GoStudent tutoring

  • Affordable 1:1 tutoring from the comfort of your home

  • Tutors are matched to your specific learning needs

  • 30+ school subjects covered

Book a free trial lesson