Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Geography > Glaciation Part 1 > Flashcards

Glaciation Part 1 Flashcards

You may prefer our related Brainscape-certified flashcards:
U.S. Geography flashcards World Geography flashcards
1
Q

Glacial

A

A prolonged cold climate phase that lasts tens of thousands of years and causes continental glaciation in middle and high latitudes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Inter-glacial

A

A period of climatic warming ( lasting 10,000 years) between glacials.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Ice age

A

A period of cold climate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Holocene

A

Lasts 12,000 years- since end of last ice age.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Epoch

A

Period of time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Quaternary

A

A geographical period ranging from 2.6 may to modern day.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Cryosphere

A

The frozen water part of the earth’s system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Glacier

A

A large mass of moving ice and snow on land

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Ablation

A

Changing from ice to a liquid or gas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Where in the would can we find ice sheets?

A

Greenland and Antarctica

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the inputs of a glacial system?

A

Precipitation, material, thermal, kinetic and potential energy.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the throughputs in a glacial system?

A

Gravitational energy, frictional energy and release of latent heat.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What percentage of the earths surface is covered in ice?

A

10%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How often do ice ages occur?

A

Every 200-500 million years.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Albedo

A

The reflection of solar radiation by the earths surface.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Accumulation

A

The build up of snow or precipitation over a period of time.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Negative feedback

A

The system will self-regulate to re-establish stability through counteracting the change and will maintain a state of equilibrium.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Positive feedback

A

A change creates a response in the system reinforces the effect of the original change, creating a snowball effect which can lead to a new state of equilibrium.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Positive mass balance

A

Accumulation > ablation
Usually occurs in winter and glacier advances.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Negative mass balance

A

Ablation > accumulation
Usually occurs in summer and glacier retreats.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Mitigation

A

Reduce the effect of something

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Open system

A

A system in which matter can enter and escape to the surroundings.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Closed system

A

A system in which no matter is allowed to enter or leave.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Aeolian processes

A

Wind can carry out erosion, transpiration and deposition which can shape glaciated landscapes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are the factors affecting glaciated landscapes?

A

Wind, precipitation and temperature.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Ventifacts

A

A landform formed by the rock being eroded by the wind.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Lithology

A

What rocks are made of. The chemical and physical composition.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What are the types of cracks?

A

Jointing, faulting, bedding and pores

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is the snow line?

A

The lower edge of permanent snow cover in upland areas.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

How is a glacier formed?

A

accumulation occurs which creates a low density layer. Where temperatures are low enough the snow will remain frozen throughout the year which will compact to a firn. Air is forced out which makes the glacier even denser.

31
Q

What are the 2 zones at a glacier?

A

Accumulation zone- higher up
Ablation zone- lower down

32
Q

What is the end of a glacier called?

A

Snout

33
Q

What are the outputs of a glacial system?

A

Ablation, calving, deposition and thermal energy.

34
Q

What are the factors influencing the decay of ice sheets?

A

Decay is a result of ablation, where summer temperatures are high and a loss of ice from calving.

35
Q

What are the short term variations in mass balances?

A

It can vary throughout the year. But typical glaciers get more accumulation in winter and more ablation in summer.

36
Q

Ice sheets

A

On land.
Thick or thin.
Greenland and Antarctica

37
Q

Sea ice

A

On sea
Thick
Arctic

38
Q

How do high latitudes affect glaciated landscapes?

A

High latitudes are high pressure bands with low levels of cloud and precipitation. So less accumulation for glaciers.

39
Q

What is the temperature decrease rate as altitude increases?

A

Temperature decreases at a rate of 6 degrees per km.

40
Q

How is faulting caused?

A

By tectonic movement.

41
Q

How is jointing caused?

A

Due to stress

42
Q

How is pores caused?

A

When water gets trapped in the rock, and freezes. It expands by 9%. The cracks get bigger overtime.

43
Q

Impact of relief on glacial systems

A

When there is a steeper relief there is more potential energy meaning that the glacier will have more energy to move faster.

44
Q

Plateaus

A

Flat land at high altitudes

45
Q

Tidewater glaciers

A

A valley glacier that reaches the sea. Forms small ice burgs

46
Q

Iceberg

A

A floating mass of ice that has been calved or broken off from the snout of a glacier.

47
Q

Outlet glacier

A

A glacier flowing out from an ice sheet, ice cap, or ice field.

48
Q

Tributary glacier

A

A small glacier flowing into a large glacier.

49
Q

Where does a glacier move the fastest?

A

Middle and the top of the glacier as there is less frictional resistance to move. The frictional resistance is from the rocks at the base.

50
Q

What are the characteristics of ice?

A

When solid and rigid the ice tends to break.
When under steady pressure the ice will deform and behave like plastic.

51
Q

Pressure melting point

A

The temperature at which ice is in the verge of melting at a given point.

52
Q

Characteristics of a warm glacier

A

High altitude.
High accumulation of snow in winter and ablation in summer
Steep gradient
Powerful erosion
Moves mainly by basal slippage.

53
Q

Characteristics of a cold glacier

A

High latitude
Low relief
Limited ablation and accumulation as there is little seasonal variation.
Moves by internal deformation.

54
Q

What is the example of a cold based glacier?

A

Meserve glacier in Antarctica

55
Q

What is the example for a cold based glacier?

A

Athabasca glacier in Canada

56
Q

How much does a cold glacier move per day?

A

1-2 cm

57
Q

How much does a warm based glacier move per day?

A

2-3 metres

58
Q

What do cold based glaciers mainly move by?

A

Internal deformation:
Intergranular flow
Laminar flow

59
Q

Inter-granular flow

A

Individual ice crystals re-oriantate and move in relation to each other.

60
Q

Laminar flow

A

The movement of individuals layers between the glacier.

61
Q

What do warm based glaciers mainly move by?

A

Basal slippage:
Regelation slip
Creep
Bed deformation

62
Q

Regelation slip

A

On the upside of an obstacle the pressure builds up causing local melting. This lubricates the movement of the ice as it reduces friction.

63
Q

Creep

A

If ice encounters a large obstacle on bedrock floor it is put under increased stain so deforms plastically and flows around the obstacle.

64
Q

Bed deformation

A

When ice is carried by saturated bed sediments moving beneath it. Water is then under high pressure.

65
Q

Extending flow

A

When ice moves over a sleep slope it can’t deform quickly and so fractures forming crevasses. The leading ice pulls away from the ice behind it.

66
Q

Compressing flow

A

As the gradient is reduced, ice thickens and the follow ice pushes over the slower-moving leading ice.

67
Q

Glacial surges and example

A

Short events where a glacier can advance substantially, moving at velocities up to 100 times faster than normal.
For example the Disko bay in Greenland that moved 10km in 4 years.

68
Q

What can cause glacial surges?

A

Hydrological (sudden increase in meltwater)
Deformable bed hypothesis (unconsummated sediment fails under stress)
Critical mass (being met and basal melting reducing friction)

69
Q

Crevasses

A

Features formed in the surface of the ice as it moves

70
Q

Marginal crevasses

A

These are a result of friction along the valley sides as the ice advances

71
Q

Transverse crevasses

A

Extend along a glacier- common as ice falls

72
Q

Longitudinal crevasses

A

Valley becomes wider and ice surface widens to fill the valley

73
Q

Radial crevasses

A

Found at the snout of a glacier.
As it moves out onto the open land and no longer constrained by the valley

Geography (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions