EQ3: Formation of glacial landforms and landscapes?

Question 1

What is glacial erosion?

Answer 1

The removal of rock material by ice through abrasion, plucking and meltwater flow from ice margins

Glacial erosion is a key process in shaping landscapes affected by glaciers.

Question 2

Define glacial debris entrainment.

Answer 2

Sediment being incorporated into glacial ice and carried along with the ice

This process is crucial for understanding how glaciers transport sediment.

Question 3

What is glacial sediment transport?

Answer 3

Sediment being moved on top of (supraglacial), within (englacial) or at the base (subglacial) of ice

Different transport mechanisms can affect the characteristics of the sediment.

Question 4

What occurs during glacial deposition?

Answer 4

Material is dropped from the ice at the margin or the base of a glacier and deposited, or deposited from meltwater

Glacial deposition results in the formation of various landforms.

Question 5

What are macro-scale glacial landforms?

Answer 5

Cirque/ corries, aretes, pyramidal peaks, glacial troughs, ribbon lakes, till plains, moraines, knock ‘n lochans

These landforms provide evidence of former glacial conditions: its extent, size, etc.

Question 6

List meso-scale glacial landforms.

Answer 6

• Roches moutonnees
• Drumlins
• Kames
• Eskers
• Kettle holes

Meso-scale landforms are intermediate in size and also indicate glacial activity.

Question 7

What are micro-scale glacial features?

Answer 7

• Striations
• Chattermarks
• Erratics

Micro-scale features provide fine details about glacial movement and processes.

Question 8

Describe proglacial areas.

Answer 8

Occur in front of ice masses where meltwater deposition and wind action on glacially eroded sediments took place

Proglacial environments are significant for sediment transport and landform development.

Question 9

What defines periglacial areas?

Answer 9

Areas that had no ice cover but were underlain by permafrost

Periglacial regions are important for studying climate conditions and their effects on landscapes.

Question 10

What is the process called when a glacier detaches large particles of rock from the bedrock?

Answer 10

Plucking

Question 11

What is quarrying in the context of glacial erosion?

Answer 11

An extreme form of plucking, creating steep and angular rock cliff faces.

Question 12

What happens during abrasion in glacial erosion?

Answer 12

Sharp rock fragments embed in the ice and grind down the bedrock, leaving scratches called striations.

Question 13

What is freeze-thaw weathering?

Answer 13

Weathering that occurs on rock slopes above valley glaciers, providing angular rock fragments.

Question 14

What is a corrie?

Answer 14

An armchair-shaped, steep-sided hollow at the head of a glaciated valley.

Question 15

What direction do corries often face in the northern hemisphere?

Answer 15

North or North East facing

Question 16

What initial process deepens the hollow of a corrie?

Answer 16

Nivation~

~ erosion of the ground around a slope of snow due to freezing and thawing

Question 17

What can accumulate behind the lip of a corrie in a post-glacial period?

Answer 17

Water, forming a tarn.

Question 18

What is an arête?

Answer 18

A narrow ridge formed when several corries lie close to one another and erode back into the mountain.

Question 19

How are pyramidal peaks formed?

Answer 19

By glaciers eroding a mountain from three or more sides, resulting in a sharp peak.

Question 20

What are glacial troughs?

Answer 20

U-shaped valleys that develop where glaciers flow into pre-existing V-shaped river valleys.

Question 21

What features characterize the formation of glacial troughs?

Answer 21

They are steep-sided with a wide, flat base and often include truncated spurs.

Question 22

What is a ribbon lake?

Answer 22

A lake formed in a rock basin created by uneven glacial erosion, often filling post-glaciation.

Question 23

What causes the formation of hanging valleys?

Answer 23

When ice in a tributary valley cannot erode effectively due to blockage by ice in the main valley.

Question 24

Fill in the blank: Glacial troughs develop where glaciers flow into pre-existing _______ river valleys.

Answer 24

V-shaped

Question 25

True or False: Hanging valleys are always larger than the main glacial trough.

Answer 25

False

Question 26

What is a truncated spur?

Answer 26

Cliffs left behind when glaciers straighten the valley and cut off spurs.

Question 27

What are rouches moutonnees?

Answer 27

Isolated rocks, generally between 5 to 30m in height, along the base of a glaciated valley ## Footnote Characteristically smooth on one side and jagged on another, formed by glacial movement over harder rock.

Question 28

How do rouches moutonnees form?

Answer 28

They form where a glacier moves over a band of harder rock, smoothing the upstream side by abrasion and leaving striations ## Footnote The downstream side is jagged due to plucking of loose rocks.

Question 29

What are knock 'n' lochan?

Answer 29

Scottish names for an irregular landscape of small ice-sculpted hills (knocks) and small lakes (lochans) ## Footnote Result from widespread abrasion and plucking by an ice sheet.

Question 30

What type of rock primarily forms knocks in the Scottish landscape?

Answer 30

Hard metamorphic rock ## Footnote This rock type is sculpted by glacial activity.

Question 31

What is a crag in the context of glacial landforms?

Answer 31

A resistant rock that forms an outstanding feature, less eroded than surrounding rock ## Footnote Represents part of the differential geology in glacial landform creation.

Question 32

What is created in the lee of a crag?

Answer 32

The tail, formed by deposition of eroded material ## Footnote This feature is characteristic of crag and tail landforms.

Question 33

What is an example of a crag and tail feature?

Answer 33

Edinburgh Castle and the Royal Mile down its tail ## Footnote Exemplifies how crags can serve as prominent landmarks.

Question 34

Fill in the blank: Rouches moutonnees are smooth on one side and _______ on another.

Answer 34

jagged ## Footnote This contrast is a key characteristic of rouches moutonnees.

Question 35

True or False: Crag and tails are formed by the erosion of the same type of rock.

Answer 35

False ## Footnote They form through differential erosion, where resistant rock remains while surrounding rock erodes.

Question 36

What are moraines?

Answer 36

Unconsolidated and unsorted angular materials created by glacial depositional processes. ## Footnote Moraines can take various forms based on their location relative to the glacier.

Question 37

What are end moraines?

Answer 37

Terminal and recessional moraines. ## Footnote Terminal moraine marks the maximum position of the ice, while recessional moraines mark the stand-still position of a glacier during melting.

Question 38

What does a terminal moraine indicate?

Answer 38

The maximum position of the ice. ## Footnote Terminal moraines are usually arc-shaped and can be tens of meters high and kilometers long.

Question 39

What is a lateral moraine?

Answer 39

Material located along the edge of valley glaciers where the ice meets the valley wall. ## Footnote Debris is constantly dropped onto the ice due to weathering and mass movement.

Question 40

What is produced when two valley glaciers meet?

Answer 40

A medial moraine. ## Footnote The respective lateral moraines merge into a medial moraine running down the middle of the larger glacier.

Question 41

What is a drumlin?

Answer 41

An oval-shaped hill often formed of moraine deposited as a glacier moves forwards. ## Footnote Drumlins indicate the direction that the glacier was flowing in.

Question 42

List the characteristics of a drumlin.

Answer 42

* Oval-shaped hill * Up to 50 m tall * 200-1,000 m long * Steeper 'stoss' end pointing up-ice * Gently sloping 'lee' end pointing down-ice * Can be rock-moulded or made of glacial sediments * Often found in groups ## Footnote The landscape can be described as 'a basket of eggs' topography.

Question 43

What is till?

Answer 43

Unconsolidated sediment deposited by a glacier, consisting of a mix of clay, boulders, and gravel. ## Footnote Lodgement till is deposited under the ice, while ablation till is deposited by melting ice.

Question 44

What do terminal moraines indicate about glacial history?

Answer 44

The extreme edge of a glacial advance. ## Footnote They provide evidence for the maximum extent of ice.

Question 45

How do drumlins provide evidence of glacial movement?

Answer 45

By their orientation and angle of long axis. ## Footnote Erratics also provide evidence of the direction of movement.

Question 46

What role does glacial meltwater play in glaciated landscapes?

Answer 46

It can erode channel networks and is involved in various fluvioglacial processes. ## Footnote Meltwater can be subglacial, englacial, or supraglacial.

Question 47

What is the difference between glacial and fluvioglacial deposits?

Answer 47

* Glacial deposits are unstratified; fluvioglacial are stratified * Glacial deposits are poorly sorted; fluvioglacial are well-sorted * Glacial deposits have random long-axis alignment; fluvioglacial have dominant directions * Glacial deposits show little sign of grading; fluvioglacial are well-graded ## Footnote These differences are significant in understanding glacial processes.

Question 48

What are eskers?

Answer 48

Long, thin ridges made of sand and gravel left behind by subglacial, englacial, or supraglacial river channels. ## Footnote They can be up to 100 m in height and extend for many kilometers.

Question 49

What are kames?

Answer 49

Irregular mounds of sands and gravels produced at the edges of a glacier or ice sheet. ## Footnote Kames often occur in groups and resemble cones or deltas.

Question 50

What are sandhur?

Answer 50

Large areas of sandy and pebbly material washed out of the ice by meltwater streams. ## Footnote They show layered deposits with larger deposits occurring each spring.

Question 51

What are kettle holes?

Answer 51

Small, often circular, lakes formed by the melting of ice blocks left by a retreating glacier. ## Footnote They can be observed in various regions, such as north Cheshire.