Glaciers and Glacial Mechanics

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Glaciers and Glacial Mechanics
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1. Glacier Origins and Types

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• Glacier Origins and Types
• Glacier (def) a body of moving ice that has been
  formed on
• land by compaction and recrystallization of snow.

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• Glacier Origins and Types
• Glacier (def) a body of moving ice that has been
  formed on
• land by compaction and recrystallization of
  snow.
• B. Critical Requirements

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• B. Critical Requirements
• Must be formed from the accumulation and
  metamorphism
• of snow.

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• B. Critical Requirements
• Must be formed from the accumulation and
  metamorphism
• of snow.
• 2. Ice must be moving under its own weight.

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• B. Critical Requirements
• Must be formed from the accumulation and
  metamorphism
• of snow.
• Ice must be moving under its own weight.
• Must originate on land

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• B. Critical Requirements
• Must be formed from the accumulation and
  metamorphism
• of snow.
• Ice must be moving under its own weight.
• Must originate on land
• Persist from year-to-year

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• Glacier Origins and Types
• C. The recrystallization of snow

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II. The Movement of Glaciers
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• II. The Movement of Glaciers
• Basal Sliding

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• II. The Movement of Glaciers
• Basal Sliding
• Plastic Flow

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• II. The Movement of Glaciers
• Basal Sliding
• Plastic Flow
• Internal Shearing

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II. The Movement of Glaciers D. Crevassing (Zone
of Fracture)
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Crevasses
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Crevasses
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• The Glacial Budget
• Zone of Accumulation
• Zone of Ablation
• Equilibrium Line

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fastest velocity at equilibrium line
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IV. Classification of Glaciers
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• IV. Classification of Glaciers
• Descriptive-based
• Process-based

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• IV. Classification of Glaciers
• Descriptive-based
• Cirque Glaciers
• Valley Glaciers
• Ice Sheets

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• IV. Classification of Glaciers
• Descriptive-based
• Process-based
• 1. Dynamic classification scheme
• Active
• Passive
• Dead

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• IV. Classification of Glaciers
• Descriptive-based
• Process-based
• 1. Dynamic classification scheme
• Active
• Passive
• Dead
• 2. Thermal classification scheme
• Temperate Glaciers

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• IV. Classification of Glaciers
• Descriptive-based
• Process-based
• 1. Dynamic classification scheme
• Active
• Passive
• Dead
• 2. Thermal classification scheme
• Temperate Glaciers
• Polar Glaciers
• --sub polar
• --high polar

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V. Erosional Glacial Landforms
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Cirques Tarn Lakes Pater Noster Lakes
Horns Aretes
U shaped Valleys Hanging Valleys Fjords
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Cirques
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Arete
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U-shaped valley
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Horn
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Fjords
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VI. Depositional Landforms
Moraines Lateral Medial
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VI. Depositional Landforms
Glacial Till
Stratified drift
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Lateral and Medial Moraines
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MorainesEnd, Terminal, Ground
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End Moraine
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Terminal moraine
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Eskers, Drumlins, Kames, Kettles, Outwash Plains,
Erratics
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Drumlin
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Esker
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Outwash plain
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The Pleistocene Epoch
Milankovitch Cycles
Eccentricity Tilting Wobble
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The Pleistocene Ice Ages Glacial
Periods Wisconsinan Illinoian Kansan Nebraskan

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Global sea level drop
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Pluvial Lakes
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J. Harlen Bretz 1923-1932
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