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Glacier Notes

GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

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Page 1: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

GlacierNotes

Page 2: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

Cryosphere

– sea ice– ice shelves– icebergs– ice sheets– glaciers

– lake ice– river ice– snow–permafrost

All of the frozen areas on Earth's surface where water exists in its solid form

Page 3: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

Glacial Overview

• What are they?• How do the form?• How do they move?• What kinds of features do they form?

Page 4: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

Glaciers  

Mass of ice formed by the recrystallization of snow under

its own weight

Compacted snow becomes “firn”

More snow has to be addedthan melted in the previous year's worth of snowfall sothat it can accumulate in layers  

Page 5: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas
Page 6: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

Types of Glaciers

1. Ice sheets (continental glaciers) -- cover large areas of land

2. Valley (alpine) glaciers -- form at mountain tops and flow down valleys

Page 7: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

Glacier: a Flowing River of Ice

• Mountain (Alpine)• Continental (Ice Sheets)

Page 8: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

How Glaciers Move

Page 9: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

Glacial Zones

Zone of Accumulation• Snowfall exceeds ablation–Ablation – reduction in glacial ice by

sublimation, melting, or calving

Zone of Melting (Ablation) (Wastage)• Ablation exceeds snowfall

Page 10: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas
Page 11: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

Anatomy of a Glacier

Page 12: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas
Page 13: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

Erosional Features

Page 14: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

U-Shaped Valley / Fjord / Trough

Page 15: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas
Page 16: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

Hanging Glacier

Page 17: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

CirqueA semicircular or amphitheater-shaped feature created as glaciers scour back into the mountain

Page 18: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

AreteSteep-sided, sharp-edged bedrock ridge formed by 2 glaciers eroding away on opposite sides of the ridge

Page 19: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

A pyramid-shaped mountain peak created by several glaciers eroding away at different sides of the same mountain

Horn

Page 20: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

Glacial StriationsLines etched in bedrock under glaciers as individual particles of rock embedded in the glacier scratch the bedrock

Page 21: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

Cirque

Arete

Horn

Page 22: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

The Matterhorn

In the Swiss alps

Page 23: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

?

?

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Page 24: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

Glacial Deposits

• Glacial deposit is called till.– Glaciers pick up everything in their path, even

the largest boulders.– Large amounts of sediment can be carried long

distances by glaciers.

Page 25: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

Depositional Features

Page 26: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

Moraines

• A mound or ridge of till deposited by a glacier

• The different places along a glacier’s advance will result in the different types of moraines– Lateral (Sides)–Medial (Middle)–Terminal (End)

Page 27: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

Lateral Moraine

Unconsolidated material deposited along the sides of an alpine glacier

Page 28: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

Medial Moraine

When two alpine glaciers flow together, their lateral moraines join, forming a medial (middle) moraine

Page 29: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

Terminal/End Moraine

Page 30: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

• The terminus of a glacier may remain stationary for years.• The sediment piles up in a ridge called an end moraine.• If this marks the furthest extent of the glacier it is a

terminal moraine.

Formation of end moraine

Page 31: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

Retreating Glacier

End moraine

Page 32: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas
Page 33: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

lateral moraine

medial moraine

Page 34: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas
Page 35: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

Esker

Long ridge formed by sediment deposition in sub-glacial streams

Page 36: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

Kettle LakesFormed by melting ice chunks in glacial debris

Page 37: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

DrumlinA long, narrow, smooth hill of unstratifited glacial till. Points in the direction of flow.

Page 38: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

Erratics

Large boulders left behind after glaciers retreat

Page 39: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

Continental Glaciation Landform Features

Southernmost extent of continental glacier

Page 40: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas
Page 41: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas
Page 42: GlacierNotes. Cryosphere – sea ice – ice shelves – icebergs – ice sheets – glaciers – lake ice – river ice – snow – permafrost All of the frozen areas

Retreat of South Cascade Glacier, Washington