Glaciation

Question 1

What kind of permanent snow do glaciers form?

Answer 1

Snowfields

Question 2

Where do snowfields occur?

Answer 2

At high altitudes and latitudes near the poles and north facing slopes.

Question 3

Name 4 places that glaciers can be found:

Answer 3

Greenland, New Zealand, Norway, Alaska

Question 4

What two ways do glacial ice flow?

Answer 4

Internal deformation and basal sliding

Question 5

What is internal deformation?

Answer 5

Individual ice crystals within a glacier deform and slide across one another.

Question 6

What is basal sliding?

Answer 6

Meltwater at the base of the glacier lubricates the ice causing it to slide.

Question 7

What 3 zones does a glacier have?

Answer 7

1. Zone of accumulation
2. Zone of flow
3. Zone of wasting

Question 8

What occurs in the zone of accumulation?

Answer 8

This is where the snow collects, turns into ice and forms features like cirques, arêtes and pyramidal peaks. The rocks above the glacier undergo frost shattering.

Question 9

What occurs in the zone of wasting?

Answer 9

This zone contains the terminal moraine ridge and outwash plain. It occurs at the snout of the glacier.

Question 10

What occurs in the zone of flow?

Answer 10

The ice moves under gravity. It erodes through abrasion and plucking. Glacial troughs, hanging valleys, waterfalls and lakes are formed in this zone.

Question 11

What are the three ways that ice erodes by?

Answer 11

1. Freeze-thaw
2. Plucking
3. Abrasion

Question 12

Freeze-thaw :

Answer 12

Water in cracks in the rock freezes and expands.
After many cycles of freezing and thawing lumps of rock are
broken off.

Question 13

Plucking :

Answer 13

Glacier ice freezes into cracks in rocks and when the glacier
moves it pulls out chunks to leave a jagged surface.

Question 14

Abrasion :

Answer 14

Rocks stuck in the ice grind away the bedrock under the
glacier.