Glaciation Flashcards

1
Q

define glacial

A

an extremely cold period of time during an ice age

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

define interglacial

A

a period of warmth during an overall period of glaciation

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

describe Britain in the last ice age

A

wooly mammoths, wolves
ice streams
extremely cold

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

define weathering

A

the breakdown of rocks in situ by the action of rainwater, biological activity and extreme temperatures

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

2 types of erosion

A

abrasion
plucking

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

describe abrasion

A

rocks at the bottom of the glacier grind against the bedrock forming sharp grooves called striations.

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

describe plucking

A

ice freezes onto large boulders which are then pulled out of the ground as the glacier advances
occurs at the back wall of corries

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

define erosion

A

the wearing down or removal of land due to flowing water, ice or wind.

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

glacial deposition

A

the glacier loses energy so it drops materials (till)

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

till

A

an unsorted mixture of materials, varies from small pebbles to large boulders

points in direction glacier moves

forms moraines

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

lodgement till

A

material deposited directly as the glacier moves forwards

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

ablation till

A

material deposited as the glacier melts

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

3 types of glacial transport

A

subglacial- material transported at the base of the glacier

englacial- material transported in the glacier

supra-glacial- material transported above the glacier

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

outwash

A

sediment carried by meltwater rivers
some outwash is rounded due to attrition by river erosion

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

accumulation

A

snow falling
build up of glacial ice due to snow being compacted into ice

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

ablation

A

snow melting
glacial ice melting during summer

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

explain rotational slip

A

snow collects on top of glacier, is heavy enough to push glacier downhill.
weight of ice on top of the glacier puts pressure on ice at the base of the glacier, so it melts
so the glacier moves by rotational slip- circular motion

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

when does a glacier retreat

A

when there is an increase in temperatures
when there is a decrease in snowfall
when ablation is greater than accumulation

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

snout

A

the end of a glacier

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

where does ablation occur

A

at the snout of the glacier

21
Q

corrie formation

A
  1. snow accumulates in depressions
    2.overtime snow becomes glacial ice
    3.freeze-thaw weathering occurs, this produces scree
    4.the scree grinds against bedrock (abrasion) so the hollow deepens due to abrasion
    5.plucking occurs as the glacier moves downhill by rotational slip, this steepens the back wall
    6.there’s less erosion at the front so a corrie lip forms
  2. when ice melts, a tarn forms
22
Q

3 conditions for freeze-thaw weathering

A
  1. frequent temperatures below and above 0 degrees
  2. supply of liquid water
  3. supply of rocks with cracks in them
23
Q

describe freeze-thaw weathering

A

water gets into cracks in rocks, it freezes and expands, then it melts
the process repeats until pressure is great enough to crack the rock completely

24
Q

when does a glacier advance

A

when accumulation is greater than ablation
decrease in temperatures
increase in snowfall

25
Q

describe bulldozing

A

rock and debris are pushed downhill by the force of moving ice

26
Q

describe rotational slip

A

circular movement of ice in a corrie

27
Q

describe moraine

A

moraine is material carried and deposited by a glacier

formed by deposition

28
Q

describe the 4 types of moraine

A

lateral- material deposited along the sides of the glacier (remain intact as they’re less likely to be eroded by meltwater)

medial- material deposited in the middle of the glacier

ground- material deposited beneath the glacier

terminal- material deposited at the end of the glacier

29
Q

what is an arête

A

2 corries eroded back to back by plucking and abrasion to form a narrow ridge between them
E.g striding edge in Lake District

30
Q

what is a pyramidal peak

A

multiple corries (3 or more) erode by abrasion and plucking back into the mountain forming a peak
E.g Mt Everest

31
Q

what is a glacial trough

A

a huge U-shaped valley
formed by erosion
the glacier cuts through interlocking spurs, forming truncated spurs

some have hanging valleys and narrow ribbon lakes

flat and wide bottom, steep sides

32
Q

what are:
hanging valleys?
ribbon lakes?

A

hanging valley is a tributary valley that is on the main valley wall, high above the main valley floor

ribbon lakes are narrow, deep freshwater lakes formed by increased vertical erosion

33
Q

describe the 3 areas where erosion increases

A
  1. when a band of weaker, easily eroded rock crosses the valley

2.when a tributary glacier joins a main glacier, this increases the glacier’s mass which increases erosion

  1. when the valley sides become narrower
34
Q

what are erratics

A

boulders carried by the glacier and deposited into an area of differing rock type

can originate from hundreds of miles away

35
Q

what are drumlins

A

smooth mounds of deposited material
formed parallel to the direction of the glacier’s movement

36
Q

how are hanging valleys formed

A

tributary glaciers flow into the main glacier
they don’t have the same erosion power as the main glacier,
so they are cut off by the main glacial valley and hang over the main valley floor

37
Q

how are U-shaped valleys formed

A

ice fills the valley

there is erosion of both sides and the floor
valley becomes straighter as ice cuts through hard rock

the glacier has lots of power and erodes slope material which widens the valley into a U shape

38
Q

tourism vs farmers conflict

A

tourists leave gates open-animals escape

dogs worry sheep

tourists litter- danger to animals

39
Q

quarrying vs conservation conflict

A

quarrying destroys habitats

makes area look unattractive

40
Q

tourism vs conservation conflict

A

tourists cause footpath erosion- makes area unattractive

more vehicles=more air pollution

41
Q

energy vs conservation conflict

A

wind farms ruin the view

wind turbines are a danger to birds

42
Q

forestry conflict

A

many trees of the same species reduces biodiversity

43
Q

reservoirs vs conservation conflict

A

disrupts fish migration

displaces locals

44
Q

define conservation

A

the act of protecting Earth’s natural resources for current and future generations

45
Q

tourism in the Lake District social pros and cons

A

pros:
-opportunities for boating, fishing, hiking

cons:
-more vehicles =air pollution=respiratory problems
-pressure on facilities
-tourists buy holiday homes- increases price of homes for locals

46
Q

tourism in the Lake District economic pros

A

pros:
-brings money to local businesses=multiplier effect
-50 million tourists a year

47
Q

tourism in the Lake District environmental pros and cons

A

cons:
-air pollution from vehicles
-footpath erosion
-conflicts

48
Q

management of issues of tourism in the lake district

A

traffic congestion-encourage public transport
go lake travel programme

footpath erosion:
-volunteer groups repair footpaths with sheep wool & stone
fix the fells project

49
Q

what is quarrying

A

removing rocks and minerals from the ground to make products

quarrying slate in the lake district- used for roofs, gardens

pollution- air, water, noise
loss of biodiversity
habitats destroyed