17

Question 1

Glacier

Answer 1

An accumulation of snow and
ice, that lasts year round.
Thick enough to flow downhill
under its own weight.

Question 2

Categories of Glaciers

Answer 2

Mountain glaciers
Continental glaciers (Greenland, Ant Artica)

Question 3

Mountain Glaciers - Cirque

Answer 3

Fill mountaintop bowls.

Question 4

Mountain Glaciers - Valley

Answer 4

Low like rivers down valleys.

Question 5

Mountain Glaciers - Ice caps

Answer 5

Covers peaks and ridges.

Question 6

Mountain Glaciers - Piedmont

Answer 6

Spread out at the end of a valley.

Question 7

Continental Glaciers

Answer 7

Vast ice sheets covering large
land areas.
Ice flows outward from thickest
part of sheet.

Question 8

Basal slip

Answer 8

Forming or belonging to
a bottom layer.
Significant quantities of
meltwater forms at glacier base.

Question 9

Plastic Deformation

Answer 9

Crevasses form at surface—upper zone is stretching.
Not reversable.

Question 10

Zone of accumulation

Answer 10

Area of net snow addition.

Question 11

Zone of ablation

Answer 11

Area of net ice loss.

Question 12

Toe

Answer 12

The leading edge of a glacier.

Question 13

Glaciers are important forces of
landscape change…

Answer 13

…Erosion, transport, deposition

Question 14

Tarn

Answer 14

A lake inside a cirque.

Question 15

Arete

Answer 15

Knife-edge ridge.
Two cirques or two
valley glaciers that have eroded
toward one another.

Question 16

Glaciers act as…

Answer 16

…large-scale conveyor belts.

Question 17

Sediment transport is always…

Answer 17

… in one direction (downhill).

Question 18

Debris at the toe of a glacier is called…

Answer 18

…end moraine.

Question 19

Moraines

Answer 19

Unsorted debris deposited by a
glacier.

Question 20

(Moraines) Lateral

Answer 20

Forms along the flank of a
valley glacier.

Question 21

(Moraines) Lateral

Answer 21

Forms along the flank of a valley glacier.

Question 22

(Moraines) Medial

Answer 22

Mid-ice moraine from
merging of lateral moraines.

Question 23

Glacial Till

Answer 23

Sediment dropped by glacial ice.

Question 24

Erractics

Answer 24

Boulders dropped by glacial ice
Different from the underlying bedrock
Carried long distances in ice.

Question 25

Loess

Answer 25

Wind-transported silt. Glaciers produce abundant amounts of fine sediment. Strong winds over ice blow the rock flour away.

Question 26

Terminal moraines

Answer 26

Form at the farthest edge of flow.

Question 26

End Moraines

Answer 26

Form at the stable toe of a glacier.

Question 27

Ground Moraine

Answer 27

Till left behind by rapid ice retreat. Creates a hummocky (irregular) surface. Kettle lakes form from stranded ice blocks.

Question 27

Drumlins

Answer 27

Long, aligned hills of molded till. ◦ Asymmetric form—steep up-ice; tapered down-ice. ◦ Commonly occur as swarms aligned parallel to ice-flow direction. ◦ Basic theory – till is dropped below glacier and as it moves over, shapes it into the shape of a teardrop.

Question 28

Eskers

Answer 28

Long, sinuous ridges of sand and gravel. Th ey form as meltwater channels within or below ice. Channel sediment is released when the ice melts.

Question 29

Consequences of Continental Glaciation

Answer 29

Ice loading and glacial rebound ◦ Ice sheets depress the lithosphere into the mantle. ◦ Slow crustal subsidence follows flow of asthenosphere. ◦ After ice melts, the depressed lithosphere rebounds. ◦ The last ice-age glacial rebound continues slowly today.

Question 30

Glacial Consequences

Answer 30

Sea level—ice ages cause sea level to rise and fall ◦ Water stored on land during an ice age: sea level falls. ◦ Deglaciation returns water to oceans: sea level rises ◦ Sea level was ~100 m lower during the last ice age. ◦ If ice sheets melted, coastal regions would be flooded.

Question 31

Pleistocene Ice Ages

Answer 31

All climate and vegetation belts were shifted southward.