1 4 Understand how moving ice acts as

1. 4 Understand how moving ice acts as an agent of erosion and deposition. (Chap. 2) There are two types of glaciation. • Alpine Glaciation • Continental Glaciation

Distinguish between the terms alpine glaciation and continental glaciation. (P. 32)

Alpine Glaciation • Alpine glaciers form high in mountain valleys; above the snow-line

C D E B A Alpine Glaciation

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

Distinguish between the terms alpine glaciation and continental glaciation. (P. 32) Similarities • Both move and cause erosion • Both change the landscape • Both developed in constantly cold < 0 0 C Differences • Location • Alpine = mountain • Continental = earth poles • Size • Alpine = smaller • Continental = larger

Define the terms outwash plain, terminal moraine, erratics, drumlins & eskers. (P. 33 Q. 12) • These features are associated with continental glaciation. • See picture p. 34

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 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 Outwash Plain

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. • P. 34

Erratic

Erratic

Continental…Erratic Terminal Moraine Outwash Plain Erratic

Drumlins p. 34 • Egg shaped hill • Formed under glaciers • Sloped or Pointy end points in direction of ice flow

Drumlins p. 34 • 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 What direction did the glacier move?

Continental…Drumlins Terminal Moraine Outwash Plain Erratic

Esker p. 34 • 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 Drumlins Terminal Moraine Esker Outwash Plain Erratic

Examine evidence for the direction of movement of glaciers. (P. 34 question # 13) 1. Sloped end of drumlin 2. Location of terminal moraine • What is direction of glacier movement in this picture?

Continental…Outwash Plain

Define the terms cirque, arête, hanging valley, lateral moraine, and terminal moraine. (P. 36) • 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 (p. 36) • 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 and as is proceeds it plucks rock from the mountain top leaving the cirque shape.

C A D E Cirque B

Cirque

Arête p. 36 • Steep, jagged, narrow, knife edged ridge between two cirques or glacier valleys.

Arete C A D E Cirque B

Arête

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

Arete C Truncated spurs A D E Cirque B

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

Arete C Truncated spurs A Horn D E Cirque B

Horn

Hanging Valley Most noticeable once glacier has melted! • 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 • Lateral Moraines

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 • Medial Moraine

Alpine Glaciation

Kaskawulsh Glacier St. Elias Mtns - Arctic

Describe how fiords are formed. (P. 37) 1. Alpine Glaciers erode troughs & valleys in the 2. mountain Glacier valley reaches the coast. 3. Glacier melts and sea water floods the valley

Fiord • A glacially eroded or modified Ushaped 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

Continental Glacier