Paper 1 Glaciers

Question 1

What is plucking in glacial erosion?

Answer 1

Plucking occurs when meltwater at the base, back, or sides of a glacier freezes onto rock, and as the glacier moves forward, pieces of rock are pulled out.

Plucking is a significant process in glacial erosion, contributing to the landscape’s alteration.

Question 2

What is abrasion in glacial erosion?

Answer 2

Abrasion is when rock frozen in the glacier grinds against the rock underneath, wearing it away.

This process contributes to the smoothing and shaping of the landscape beneath glaciers.

Question 3

What is freeze-thaw weathering?

Answer 3

Freeze-thaw weathering occurs when water freezes in cracks in the rock and expands, further cracking the rock and causing pieces to break off.

This process is a key mechanism of weathering in cold climates.

Question 4

How does the weight of ice affect glacier movement?

Answer 4

The weight of the ice makes the glacier move downhill.

This movement is crucial for the glacier’s ability to erode and shape the landscape.

Question 5

What is rotational slip in glacier movement?

Answer 5

Rotational slip is when the top end of the glacier moves in a circular motion, which can erode landforms in the landscape.

This type of movement can lead to significant changes in the terrain.

Question 6

What regions were covered by ice during the last glacial period?

Answer 6

During the last glacial period, ice covered most of Scotland, Ireland, and Wales.

Approximately 30% of England was not glaciated, but ice reached as far south as Bristol.

Question 7

what is an arête

Answer 7

a narrow steep sided ridge

Question 8

how is an arête formed

Answer 8

when 2 glaciers erode in parallel valleys and the glaciers erode the sides of the valleys, sharpening the ridge

Question 9

example of an arête

Answer 9

striding edge, lake district

Question 10

what is a pyramidal peak

Answer 10

a pointed mountain peak with at least 3 sides

Question 11

how is a pyramidal peak formed

Answer 11

by at least 3 glaciers eroding back to back

Question 12

example of a pyramidal peak

Answer 12

Snowdon, Wales

Question 13

How is a corrie formed?

Answer 13

• begins as a hollow containing a small glacier
• ice moves by rotational slip and erodes the hollow into a steep-sided armchair shape with a lip at the bottom end

Question 14

what can a corrie form when the ice melts

Answer 14

a tarn- a small, circular lake
eg. Red Tarn, Lake District

Question 15

what is a ribbon lake

Answer 15

a long,thin lake that forms after glacial retreat

Question 16

where do ribbon lakes form?

Answer 16

in hollows where softer rock was eroded more than harder rock

Question 17

example of a ribbon lake

Answer 17

lake Windermere, lake district

Question 18

what is a truncated spur

Answer 18

a cliff-like edge on the side of a valley

Question 19

how are truncated spurs formed

Answer 19

formed when ridges of land that stick out into the main valley are cut off as the glacier moves past

Question 20

what are hanging valleys?

Answer 20

valleys formed by smaller glaciers that flow into the main glacier

Question 21

why are hanging valleys at a higher level that the valley of the large glaciers

Answer 21

the glacial trough is eroded much more deeply by the large glacier, leaving the hanging valleys at a higher level

Question 22

what is a glacial trough

Answer 22

a steep-sided valley with a flat bottom

Question 23

how are glacial troughs (or U-shaped valleys) formed?

Answer 23

they start of as a v-shaped river valley, changing to a U shape as the glaciers erode erodes the sides and bottom, making it wider and deeper

Question 24

what are drumlins

Answer 24

elongated hills of glacial deposits

Question 25

what do drumlins look like?

Answer 25

they have round, blunt and steep upstream ends, and are tapered, pointed and sloping at the downstream end.

Question 26

what are erratics

Answer 26

rocks that have been picked up, carried and dropped by a glacier they are dropped in an area with a completely different rock type and therefore often look out of place

Question 27

what is glacial till

Answer 27

an un sorted mixture of material moved by a glacier

Question 28

glacial till was either… (3)

Answer 28

- frozen in the glacier - carried on its surface - bulldozed

Question 29

what is bulldozing

Answer 29

when ice pushes the loose material in front of it

Question 30

what happens to very fine material (eg sand and gravel) as till?

Answer 30

it can get washed away from the front of the glacier by meltwater streams

Question 31

what do the meltwater streams do to the fine material

Answer 31

sort the material by side and deposit it in layers (outwash) infront of the glacier

Question 32

what are moraines

Answer 32

landforms made from till dropped by a glacier as it melts

Question 33

what are the 4 types of moraines

Answer 33

lateral medial terminal ground

Question 34

what are lateral moraines

Answer 34

material deposited where the side of the glacier was

Question 35

how are lateral moraines formed

Answer 35

by material eroded from valley walls and material carried on ice surface on the sides of the glacier

Question 36

what are medial moraines

Answer 36

material deposited along the centre of a valley floor

Question 37

how are medial moraines formed

Answer 37

when 2 glaciers meet, their lateral moraines join and form the medial moraines of the new glacier

Question 38

what are terminal moraines

Answer 38

built up material at the glacier snout, marking the furthest point reached by the ice

Question 39

what forms terminal moraines?

Answer 39

plucked and abraded material that is then deposited in semicircular mounds

Question 40

what are ground moraines

Answer 40

eroded material that was dragged along the base of the glacier

Question 41

where are ground moraines deposited

Answer 41

over wide areas on the valley floor as the ice melts