Understand how moving ice acts as an agent of erosion and deposition. There are two types of glaciation



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Understand how moving ice acts as an agent of erosion and deposition.

  • There are two types of glaciation.

  • Alpine Glaciation

  • Continental Glaciation


Distinguish between the terms alpine glaciation and continental glaciation.



Alpine Glaciation







Continental Glaciation

  • Continental glaciers cover parts of continental land masses; ex Greenland





Distinguish between the terms alpine glaciation and continental glaciation.

  • Similarities

  • Both move and cause erosion

  • Both change the landscape

  • Both developed in constantly cold < 0 0C



Define the terms outwash plain, terminal moraine, erratics, drumlins & eskers.

  • These features are associated with continental glaciation.



Outwash plain

  • Similar to a river delta

  • Melt water flowing from the glacier deposits silt

  • Deposited in layers

  • Small particles carried further away

  • Larger particles drop closer to the glacier



Outwash Plain



Continental…Outwash plain



Continental…Outwash plain



Continental…Outwash plain



Terminal moraine

  • Heap or ridge of bulldozed gravel that marks the end of the forward motion of a glacier

  • As glacier retreats it deposits debris/gravel

  • P. 34



Continental…Terminal Moraine



Continental…Terminal Moraine



Erratics

  • Large boulders that were transported long distances and dropped

  • They now sit in a region and look very much out-of-place.



Erratic



Erratic





Continental…Erratic



Drumlins



Drumlins

  • Formation

    • Ice melts under glacier
    • Deposits of gravel made
    • Glacier moves forward
    • Deposits are bull-dozed along and catches up in rough areas forming piles or drumlins.


Drumlin



Continental…Drumlin



Esker

  • Long deposits of eroded glacial material

  • Formed by sub-glacial streams that deposit material like all rivers.

  • Highways of the North!!



Esker



Esker



Continental…Esker



Examine evidence for the direction of movement of glaciers.

  • Sloped, pointed, narrow end of drumlin

  • Location of terminal moraine

  • What is direction of glacier movement in this picture?



Define the terms cirque, arête, hanging valley, horn, lateral, medial and terminal moraine.

  • These features are associated with alpine glaciers



Alpine glaciers

  • Alpine glaciers are like very slow moving rivers of ice flowing down high mountain valleys.



Cirque

  • a circular hollow cut into bedrock during glaciation

  • Side and back walls are steep but front wall opens downward



Cirque - How formed?

  • Alpine glacier freezes onto mountain valley

  • As it proceeds it plucks rock from the mountain top leaving the cirque shape.





Cirque



Arête

  • Steep, jagged, narrow, knife-edged ridge between two cirques or glacier valleys.





Arête



Truncated Spur

  • Blunt-ended ridge of rock jutting from the side of a glacial trough, or valley





Horn or Pyramidal Peak

  • is a mountaintop (peak) that has been modified by the action of ice during glaciation.





Horn



Hanging Valley

  • A high level tributary valley from which the ground falls sharply to the level of the lower, main valley.

  • The depth of the lower valley is due to more severe glaciation.



Hanging Valley



Hanging Valley



Hanging Valley in Newfoundland

  • Hanging Valley in Gros Morne National park

  • Trout River pond





Lateral Moraine

  • Moraine means 'rock waste'.It is also known as glacial till

  • Lateral Moraine is the land-form deposited at the side of a glacier

  • Debris/waste rock drops off the side of the mountain as the glacier moves forming a ridge of debris at the outer-sides of the glacier.



Lateral Moraine



Kaskawulsh Glacier St. Elias Mtns - Arctic



Terminal Moraine

  • deposits that mark the farthest extent of the glacier

  • Good indicator of the direction or movement of the glacier as well.



Alpine Glaciation

  • Terminal Moraine



Medial Moraine

  • This is a ridge of rock waste found along the middle of the floor of a u - shaped valley.

  • It occurs when two glaciers meet, two lateral moraines unite to form a medial moraine.



Medial Moraine











Medial Moraine

  • Medial Moraine





Kaskawulsh Glacier St. Elias Mtns - Arctic



Describe how fiords are formed.

  • Alpine Glaciers erode troughs & valleys in the mountain

  • Glacier valley reaches the coast.

  • 3. Glacier melts and sea water floods the valley



Fiord

  • A glacially eroded or modified U-shaped valley that extends below sea level and connects to the ocean… filled with seawater.



Gross Morne - Fiord



Fiord in Norway

  • Norway is well known for its abundant fiords




















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