3.1.4.3 Geomorphological Processes 2

Question 1

Define erosion

Answer 1

The wearing away of the lands surface; including the breakdown of rock + its removal by wind,water and ice

Question 2

Define weathering

Answer 2

The breakdown of rocks in situ, producing finer particles that can be moved by erosion

Question 3

What’s is situ

Answer 3

In original location without being moved

Question 4

What does weathering produce used by glaciers for erosion

Answer 4

Debris

Question 5

What’s the main type of weathering cold environments

Most important process

Answer 5

Physical weathering
Frost shattering (freeze thaw action)

Question 6

3 ways material is transported in a glacier

Answer 6

Supraglacial (surface) debris
Englacial (inside) debris
Subglacial (under) debris -> rolled and carried on bed

Question 7

What’s moraine

4 types

Answer 7

Material left behind once a glacier melts, creating a landform

Lateral moraine (sides)
Medial moraine
Terminal moraine (at snout)
Englacial moraine (in)

Question 8

What makes up the medial moraine

Answer 8

2 lateral moraine tributaries meeting

Question 9

Where does glacial erosion occur

Answer 9

Ice-rock interface (meeting point)

Question 10

What type of ice has more of an erosive effect (2)

Answer 10

Ice moving

Ice carrying loose debris

Question 11

4 processes of glacial erosion

Answer 11

Abrasion
Plucking
Rotational Movement
Extending - compressing flow

Question 12

What’s abrasion also known as

Answer 12

The sandpaper effect

Question 13

When does plucking occur

Answer 13

During regelation slip when ice freezes

Question 14

Where does maximum erosion occur (3)

Answer 14

Where temps fluctuate around 0* allowing freeze-thaw

In areas of jointed rocks

Where 2 tributary glaciers join/valley narrows giving increased ice depth

In steep mountainous regions where velocity is greatest (temperate)

Question 15

What’s abrasion

Answer 15

Sandpaper effect as ice grinds over + scours a landscape

Question 16

What will form from erosion on bedrock

Answer 16

Striations

Question 17

What happens to the large rocks under ice over time due to erosion

Answer 17

They get pulverised by the weight and form fine rock flour

Question 18

What does fine rock flour do to the bedrock

Answer 18

Smooth + polish it

Question 19

Describe plucking

Answer 19

When meltwater freezes part of the underlying bedrock to the glaciers base and any loosened fragments will be ‘plucked’ away as the glacier slips forward

Question 20

Where is plucking particularly common

Answer 20

Where a reduction in pressure under ice has led to regelation (refreezing of meltwater in regelation slip)

Question 21

Eg of an extending flow crevasse

Answer 21

Bergschrund crevasse

Question 22

Describe frost shattering (freeze thaw)

Answer 22

Water enters joints and freezes during cold nights

Ice occupies around 9% more volume than water + exerts pressure within the joint. This alternating freeze-thaw process slowly widens the joints

bits to break off from the main rock body