Glaciation

Question 1

List the 4 types of cold enviroments

Answer 1

Glacial

Polar

Periglacial

Alpine

Question 2

List some characteristics of glacial enviroment

Answer 2

Permantly covered in ice(all year round)

Very few plants- some algae and moss

Weather can be warm enough for meltwater to impact glaciers

Question 3

List some characteristic of a polar region

Answer 3

Very cold- never above freezing, winter below -40 degrees

Very little precipitation

Little soil- when present lacks nutrients and has permafrost below it

Very few plants in polar regions

Question 4

List some characteristics of periglacial environments

Answer 4

Occur in high altitudes and latitudes

Constantly below freezing

NO ICE LOCATED HERE.

Cold and little precipation (380mm or less each year)

Grasses are more common(thin acidic soil)

Layers of permafrost dominate the floor space

Plants grow but very slowly and not very tall due to strong winds

Question 5

List some characteristics of an alpine environment

Answer 5

Located about the trees line(above where trees can grow)

Found in high altitudes

Cold winters, but summers can be mild

Tend to have higher snow fall at higher altitudes

Plants can grow due to having clear seasons

Question 6

List some inputs of a glacier

Answer 6

Snow

Condensation of water vapour(which freezes)

Deposition of water vapour

Bits of rock/ debris from glacial movement

Question 7

List some stores of a glacier

Answer 7

Ice and glacier itself

Meltwater stored within the glacier

Rock stored in or on the glacier

Question 8

What are some flows of a glacier

Answer 8

Meltwater

Debris

Question 9

What are some outputs of a glacier

Answer 9

Ice

Meltwater

Surface snow

Snout of the glacier

Question 10

Define accumulation

Answer 10

The input of snow and ice to a glacier

Question 11

Define ablation

Answer 11

Output of water from glacier

Question 12

Define mass balance

Answer 12

Balance between the amount of accumulation and ablation occurring within a year

Question 13

What is the equilibrium point ?

Answer 13

Where the accumulation and ablation of a glacier are EQUAL

Question 14

What is the zone of accumulation

Answer 14

Where more accumulation occurs than ablation with the upper part of a glacier

Question 15

What is the zone of ablation

Answer 15

Where more ablation occurs that accumulation at the lower part of a glacier

Question 16

What is positive regime

Answer 16

More accumulation= growth and advancement of snout

Question 17

What is negative regime

Answer 17

More ablation= shrinking and retreating of a glacier

Question 18

Define dynamic equilibrium

Answer 18

Where’s accumulation and ablation are the same= causing for the glacier to remain in the same place

Question 19

What is positive feedback

Answer 19

Glaciers response to change in a way which makes the change greater

Question 20

What is negative feedback

Answer 20

When inputs or outputs change

Question 21

Explain what a cold based glacier is and how it impacts erosion

Answer 21

Found in very cold areas- hardly any melting in summer- glacier doesn’t cause much erosion

Base is usually BELOW the ices melting point( very little melting) resulting in very little movement due to ice being frozen

Question 22

Explain what a warm based glacier is and how it impacts erosion

Answer 22

Found in milder areas(warmer areas)

Bases are warmer than the melting point of ice( more meltwater)

This is due to the heat from friction because the glacier moves or because of geothermal heat

More ice melts at the bottom, causing for the meltwater to act as a lubricant and makes movement easier, this then causes for lots of erosion as the glacier moves down the valley

Question 23

Explain the process of nivation

Answer 23

1) snow gets into the hollow

2) temperature flucates around 0 degrees=resulting in lots of FREEZING AND THAWING

3) when frozen it expands= frost shattering occurs, leading to bits of rock being broken off, eroding it

4) slope collapses due to build up of meltwater due to THAWING- resulting in waterlogged and erosion

5) hollow becomes deeper and wider

Question 24

Explain the process of freeze thaw weathering( frost action)

Answer 24

1) temperature fluctuates above and below freezing

2) water from thawing enters cracks in rocks and ridges

3) temperature drops and water freezes and expands- creating bigger cracks in the rocks

4) repeated freeze thaw creates further cracks- leading to bits of rock falling off

Question 25

What is plucking

Answer 25

Ice at the bottom of the glacier thaws, then refreezes causing for bits of debris to get trapped. When the glacier advances this debris is plucked out due to the joints and causes for them to be removed and carried down the valley

Question 26

Define abrasion

Answer 26

Debris carried/entrained by the glacier, scrapes the wall and valley floor/ the debris is stuck underneath the glacier and erodes the valley floor

Question 27

What is basal sliding ?

Answer 27

Meltwater underneath a glacier allows the glacier to slide over the ground. ( this is because the meltwater acts as a lubricant)

Question 28

What is rotational flow

Answer 28

Glacier move in a arc shape when there is a hollow

Question 29

What is internal deformation ?

Answer 29

The ice bends and warps to flow down hill like a liquid. Caused by ice crystal shifting past each other

Question 30

What are the 3 ways glaciers carry material

Answer 30

1) supraglacia(on top) 2) englacial(within) 3) subglacial(at the bottom)

Question 31

Define till (boulder clay)

Answer 31

Till is the unsorted mixture(from boulders to pebbles) of material deposited by the glacier

Question 32

Where and how is lodgement till spread

Answer 32

It is spread onto the valley floor( beneath the ice) by moving glacier

Question 33

What landform is till often deposited to form ?

Answer 33

Moraine

Question 34

What is an arête

Answer 34

A steep sided ridge

Question 35

How is an arête formed ?

Answer 35

Is it’s formed when two glaciers flow parelel in valleys. The glaciers erode the sides of the valley which sharpens the mountain ridge in between the,

Question 36

What is a pyramidal peak and how is it formed ?

Answer 36

Is a pointed mountain peak with at least three sides. It forms where three of more corries form back to back(their back walls make the mountain peak)

Question 37

What is a glacial trough( u-shaped valley and how is it formed ?

Answer 37

It is a steep sided valley with flat bottom. They are formed by the erosion of a v-shaped river and valley by a glacier. As the glacier erodes through the v-shaped valley it makes it deeper and wider

Question 38

What is a tarn

Answer 38

A tarn is a lake that forms in a corrie after a glacier has retreated

Question 39

What is a rouche moutonee and how is it formed

Answer 39

Is a resistant(hard) mass of rock on the valley floor. The upstream side is moth because it was smoothed by abrasion as the glacier went over it. The downstream side is steep and jagged where the glacier plucked at it

Question 40

How is a truncated spur formed ?

Answer 40

Are formed when ridges of land(spurs) that stick out into the main valley are chopped off(truncated) as the main valley glaciers moves past.

Question 41

Explain the formation of a corrie

Answer 41

Snow collects in a hollow and turns into ice. Basal sliding with abrasion and plucking deepen the hollow into a Corrie( a bowl shaped hollow) When the ice in the hollow is thick enough, it flows over the lip and downhill as a glacier. Frost shattering and plucking steepen the back walls of the Corrie

Question 42

What is the albedo effect