WBBSE Class 10 Geography Solutions Chapter 1.3 Works of a Glacier

Detailed explanations in West Bengal Board Class 10 Geography Book Solutions Chapter 1.3 Works of a Glacier offer valuable context and analysis.

WBBSE Class 10 Geography Chapter 1.3 Question Answer – Works of a Glacier

Answer in short : 2 Marks

Question 1.
What is a glacier?
Answer:
A glacier is a moving body of snow and ice which under the influence of gravity moves slowly over the land downslope.

Question 2.
What is an avalanche?
Answer:
Huge amount of snow and ice breaking off and falling along steep slopes of mountains is called an avalanche.

Question 3.
Classify glaciers.
Answer:

Question 4.
What are continental glaciers?
Answer:
In higher latitudes, glaciers cover almost the whole continent due to immense cold. These are called continental glaciers. Eg. – glaciers in Antarctica, Greenland, Iceland etc.

Question 5.
What are valley glaciers?
Answer:
Glaciers that flow through mountain valleys in higher latitudes and higher altitudes are called valley glaciers. Eg-Siachen glacier in the Karakoram range.

Question 6.
What are piedmont glaciers?
Answer:
When glaciers of higher latitudes reach the foothills of mountains, they still don’t melt due to immense cold. These are called piedmont glaciers.

Question 7. a
What is an arete?
Answer:
The thin steep ridge of the mountain lying between two adjacent corries is called an arete.

Question 8.
What is a pyramid peak ?
Answer:

When three or more corries are created on the surface of the same mountain, the sharp edged landform thus created looks like a pyramid. This is called the pyramid peak.

Question 9.
What are eskers?
Answer:

Long ridge of material deposited parallel to the direction of flow of glacial melt water is called an esker.

Question 10.
What are erratics?
Answer:
When glaciers melt, the boulders get deposited in an area where they may be a total mismatch with the surroundings. These are called erratics.

Question 11.
What are outwash plains?
Answer:

Materials washed out by glacial melt water and deposited in a variety forms are called outwash plains.

Question 12.
What are kettle lakes?
Answer:
The melt water from glaciers may get accumulated in holes created in outwash plains due to melting of detached mass of ice that might have been left partly or wholly buried. These are called kettle lakes.

Question 13.
What is an iceberg ?
Answer:
The huge masses of ice floating in the oceans are called icebergs. If continental glaciers spread till the coastline, the ocean currents cause the ice at the edge of the glaciers to break and float in the water. 8/9th parts of the icebergs lie beneath the water and only 1/9th part is seen above the surface.

Question 14.
What is snowline?
Answer:
The imaginary line above which the snow never fully melts or below which line, snow starts to melt is called mountain. The height of this line varies one climatic region to another.

Question 15.
What do you know about end moraines ?
Answer:
Moraines refers to the deposition by glaciers at the foothill region. When the shape of this depositions are horse-shoe shaped and have concave slopes, they are called end moraines.

Question 16.
What is paternoster lake?
Answer:
A glacier encountering weaker rocks at its base, will be able to erode deeper than when it experiences harder, less erodable rocks. As the glacier melts, lakes form where weaker rock was excavated, this lakes are called paternoster lake.

Question 17.
What is a nunatak?
Answer:
In a continental glacier, near the edges, where the ice layers are not so thick, some hills or domes may rise above the snowy surface, which have no deposition of snow on them. These bare rocky outcrops within the glacial snow are called nunataks.

Question 18.
What are the characteristics of continental glaciers ?
Answer:
The characteristics of continental glaciers are :

1. These glaciers are larger in volume and size than other types of glaciers.
2. These glaciers are thicker at the middle and thinner at the edges. Hence they look like domes.
3. Depth of these glaciers is greater compared to other glaciers.
4. The direction of flow of continental glaciers is from the centre towards the edges from all sides.
5. The edges of these glaciers break off to form icebergs.

Question 19.
What is a snout?
Answer:
In valley glaciers, the mass of ice flows through specific valleys. The walls and base of the valley provide immense friction and try to prevent the ice from flowing. Hence, the middle part of the glacier, which experiences less friction, seem to move forward. This appears like a tongue-shaped feature. This is known as the snout of the glacier. The snow of the snouts gradually melts to give rise to rivers.

Question 20.
Why are pyramidical peaks also called ‘horns’?
Answer:
The Matterhorn peak in Switzerland is an example of a pyramid peak. Hence, following the name of the peak, the pyramidical peaks are also called horns.

Question 21.
What is boulder clay ?
Answer:
Glaciers deposit unassorted load or debris when they start melting. If big boulders get deposited over a field of sandy and clayey deposits, the landform is called boulder clay or till.

Question 22.
What do you mean by a ‘Basket of eggs’ topography ?
Answer:
When numerous drumlins are formed due to glacial deoposition very close to each other, the region looks like numerous eggs placed in a basket. Hence, such a topograhy is called a ‘Basket of eggs’ topography.

Question 23.
What is an Agamuk ?
Answer:
The huge chunks of boulders and rock fragments deposited near mountains due to depositional work of glaciers form a typical landform called Agamuk.

Question 24.
What is an ice sheet?
Answer:
An ice sheet is a large mass of ice that covers the surrounding terrain and is greater than 50,000 km². This is also known as continental glacier.

Question 25.
What is crag and tail ?
Answer:
In a glaciated region, if any huge hard block of rock lies inbetween soft rocks, the glacier erodes the softrock while climbing up the huge hard rock. The soft rocks lying at the back of the hard rock from where the glacier descends, does not get eroded much compared to the front. Thus, the huge hard rock standing out is known as the crag and the band of softrock lying at the back is known as the tail.

Question 26.
What do you mean by ice age?
Answer:
Ice age is a period of long-term reduction in the temperature of the earth’s surface and the atmosphere, resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers.

Question 27.
What are neve and firn?
Answer:
Neve is a granular, porous type of snow which has been partially melted, refrozen and compacted, leading to the formation of glacial snow. This forms the surface of the upper-end of the glacier. Firn is partially compacted neve. It is a type of snow that has been left over from the past seasons and has been recrystallized into a substance denser than neve. It is intermediate between snow and glacial ice.

Answer briefly : 3 Marks

Question 1.
How is a glacier formed ?
Answer:
In higher latitudes and higher altitudes, the regions above the snowline accumulated much snow due to immense cold. This snow is gradually compacted and converted to ‘neve’. This storage of ice gradually flows down the slope of land, hence forming a glacier.

Question 2.
What is a Bergschrund ?
Answer:
A Bergschrund is a long narrow crack developed at the source of the glacier. This is created when the mass of ice tends to flow down due to gravity and the mountain walls tend to hold back the ice due to friction.

Question 3.
Mention the methods by which a glacier erodes.
Answer:
The glacier can erode by the following methods:
(a) Plucking : As the glacier starts moving, the solid mass of ice plucks out any protruding rock that comes in the way. This is called plucking.
(b) Abrasion : As the glacier moves forward, the already plucked rock fragments rolls against the floor and walls of the valley and also against each other. This makes the rock fragments rounded and smooth. This is called abrasion.
(c) Frost Wedging : When glacial ice melts partially, the water percolates into the adjacent cracks and joints. Once again when it freezes, the volume of water (as ice) increases and exerts pressure on the walls of the cracks. Thus rocks break apart. This is called frost wedging.

Question 4.
What is a fjord?
Answer:
In higher latitudes, the glaciers near sea coasts erode their valleys so deeply that the base of the valleys seem to get lowered than the sea level as well. These regions get filled up with sea water and the higher walls look like gradually submerged ridges. Such a reigion is called a fjord. Eg-‘Sogne’ fjord of Norway.

Question 5.
Why are waterfalls common in hanging valleys ?
Answer:
In mountainous regions, where the smaller glaciers meet the main glacier, the main glacier curves deeper valleys than the smaller glaciers. When the ice melts, these smaller glacier valleys seem to hang over the main glacial valley, which is quite deeper. When water flows through the hanging valleys into the main valley, they obviously form waterfalls.

Question 6.
Why is the position of the snowline flexible ?
Answer:
The presence of permanent snow varies or depends on several factors – eg. latitudes, height, slope, season, wind direction, wind speed, heat content etc. Change in any of the factors results in melting of ice or falling of new snow. Hence, the previous snow line may get changed. Thus the snowline is flexible.

Question 7.
What is a drumlin ?
Answer:
Drumlins are long narrow deposition of boulders and clay brought down by glaciers at the foot hills of the mountains. They look like inverted boats. They are also known as ‘Basket of eggs’ topography.

Question 8.
Classify moraines.
Answer:
Moraines are the depositions of rock fragments and clay brought down by glaciers and deposited along their path of movement. They can be classified as :

(a) Side moraines : When the debris is deposited along the side walls of the glacial valley, they are known as side moraines.
(b) Medial moraines : When two glaciers meet, the side moraines of both the glaciers on one side tend to merge with each other. This deposition continues for a considerable distance and lies in the middle of the newly joint glacier.
(c) End moraines : When debris is deposited at the end of the glacier after which it starts melting into water, it is known as end moraines.

Question 9.
Differentiate between Roche moutonnee and Drumlin.
Answer:

Roche moutonnee	Drumlin
i. This looks like a high heap of rocks.	i. This looks like an egg basket or inverted boat.
ii. This is an erosional landscape of glaciers.	ii. This is a depositional landscape of glaciers.
iii. The side along the flow of the glacier is smooth, while the other side is rough.	iii. The side along the flow of the glacier is rough and the other side is smooth.
iv. This may lie single.	iv. This usually lies in groups.

Question 10.
Differentiate between Continental and Mountain Glaciers.
Answer:

Continental Glaciers	Mountain Glaciers
i. This occupies huge landmasses and spreads over almost the continents.	i. This occupies mountain valleys of high altitudes and high latitudes.
ii. Largest of all glaciers.	ii. Comparatively smaller glaciers.
iii. Usually depth of ice is very high.	iii. Usually have lesser depth of ice.
iv. Eg. – Lambert in Antarctica.	iv. Eg. – Gangotri, Yamunotri etc. of the Himalaya.

Question 11.
What are crevasses?
Answer:

Crevasses are cracks formed on the surface of glaciers. If the glaciers flow over a uniform slope throughout, crevasses are not formed. But if the surface underlying the snow is rugged and undulating, the glacier has to ride the higher parts and slope down the lower parts. Thus, a great force of tension works on the snow. This creates the crevasses.

Question 12.
On what factors does the erosive power of glaciers depend?
Answer:
The erosive power of glaciers depend on the following factors :

1. Speed : If the glaciers have greater speed, they have greater rate of erosion.
2. Depth of ice : Greater the depth of ice of the glacier, greater is its erosive power.
3. Permanency of the glacier : If the glacier remains so for a long period of time, its rate of erosion will also be much greater.

Question 13.
What is ‘Snowline’?
Answer:
Snowline is the boundary that marks the existence of permanent snow beyond a certain altitude due to very cold atmospheric conditions. According to F. J. Monkhouse, snowline indicates the lowest edge of continuous snow cover.

Question 14.
Name the different landforms created by glaciers in higher altitudes.
Answer:
The landforms created by glaciers on higher altitudes are – corrie or cirque, cirque lakes, arete, pyramid peak or horn, hanging valleys, spurs, fjords etc.

Question 15.
Name the different landforms created by glaciers in lower altitudes.
Answer:
The landforms created by glaciers on lower altitudes are – roche moutonnee, crag and tail, drumlin, esker, agamuk, till, kettle, kettle lakes, outwash plains etc.

Question 16.
Differentiate between a river valley and glacial valley.
Answer:

River Valley	Glacial Valley
i. V-shaped or I-shaped valleys are formed by rivers.	i. Glaciers form U-shaped valleys.
ii. In upper course, the down cutting of valley is more than side cutting.	ii. In glacial valleys, side cutting is more compared to down cutting.
iii. The valley walls are steep and the base is narrow.	iii. The valley walls are steep and the base is broad.
iv. Valleys in most regions are called gorges and those in dry regions are called canyons.	iv. Glacial valleys are of different types, eg-Alipne, Iceland type, mixed type etc.

Answer in details : 5 Marks

Question 1.
Explain the formation of corrie, arete and pyramidal peak by glacial erosion.
Answer:

Corrie, arete and pyramidal peak are landforms formed by mountain glaciers in the higher altitudes near the source of the glaciers.
(a) Corrie or cirque : Corrie or cirque in an armchair shaped or amphitheatre or spoon shaped depression created by the glacier on the higher slopes of the mountains from where the glacier starts flowing.
(b) Arete : The steep narrow sharp ridge like landform lying between two adjacent cirques are known as arete.
(c) Pyramidal peak : If three or more glaciers descend from the same mountain, formation of cirques and arete all around give a sharp and steep look to the peak, resembling a pyramid. This is known as the pyramidal peak.

Question 2.
Describe the formation of hanging valley and Roche moutonnee.
Answer:
Hanging Valley : In high altitudes, many small glaciers may come and meet with a large or main glacier. The smaller glaciers have lesser ice content and hence lesser erosive capacity than the main glacier. Hence, the valleys curved by smaller glaciers are lesser in depth than the main glacier. When the ice melts, these smaller glacial valleys seem to hang over the main glacial valley. This kind of a landform is called a hanging valley.
i
Roche moutonnee : If any resistant rock lies in the path of a glacier, the flowing ice and rock fragments polish the surface of the resistant rock on the side in the direction of flow of the glacier. The other side of the rock is scooped, scraped and plucked by the rock fragments and ice, thus making the surface rough and rugged, as the glacier moves forward. Such a landform, resembling the ‘back of a sheep’ is called a roche moutonnee.

Question 3.
Describe some landforms formed by glacial deposition.
Answer:
The landforms formed by glacial deposition are :

i. Moraines : Any landform formed by depositions of valley and continental glaciers is called moraines. The moraines can be mainly of three types – (a) Moraines deposited along side of glacial valley floor are called lateral moraines. (b) Where two lateral moraines of adjacent glaciers combine, the deposition lying in the middle of the main glacier is called medial
moraine. (c) Moraines deposited at the end of a glacier are called terminal or end moraines.

ii. Eskers : Long ridges of material deposited parallel to the direction of the flow of glacial melt water are called eskers.

iii. Erratics : These are depositions of boulders and rock fragments in an area where they are a total mismatch with the surroundings.

iv. Drumlins : These are low elongated hills formed by glacial deposits. They are also called ‘Basket of eggs’ topography.
v. Kames: These are small rounded hillocks of sand and gravel.
vi. Outwash plains : These are materials

Question 4.
Compare and contrast between the works of river and glacier.
Answer:

Item	Works of river	Works of glacier
(i) Definition	A flowing body of water coming downslope from high lands to lowlands due to gravity, meeting any sea, ocean, lake etc. is called a river.	A flowing body of huge amount of ice coming downslope from a mountainous region due to gravity is called a glacier.
(ii) Speed	Rivers have great speed in the mountainous region, medium speed in plateau region and less speed in the plains.	Glaciers have yery low speed throughout the course.
(iii) Path	River finds its path avoiding any obstacle by taking curves.	Glacier tends to flow in a straight path removing any obstacle that comes in the way.
(iv) Working capacity	Depends on slope of land, quality of rocks in the channel and water content.	Depends on amount of ice, slope of land and quality of rocks in the channel.
(v) Works	Erosion, transportation and deposition.	Erosion, transportation and deposition.
(vi) Methods of erosion	Hydraulic action, corrasion or abrasion, attrition, solution.	Plucking, abrasion and frost wedging.
(vii) Type of erosion	Mechanical and chemical	Only mechanical
(viii) Valley	V-shaped	U-shaped.
(ix) Erosional landforms	Gorge, canyon, waterfalls, pot hole, plunge pool, interlocking spur etc.	Corrie, arete, pyramid peak, hanging valley, roche moutonnee, crag and tail etc.
(x) Depositional landforms	Alluvial fan and cone, flood plain, natural levee, delta, sand bar, braided channel etc.	Moraines, eskers, kames, drumlin, erratics, outwash plains etc.

Multiple Choice Question (MCQ) :

Question 1.
Which of these regions has continental glaciers ?
(A) Himalaya
(B) Alps
(C) Andes
(D) Greenland
Answer :
(D) Greenland

Question 2.
Which landform is created by glacial erosion ?
(A) Arete
(B) Moraine
(C) Drumlin
(D) Plunge pool
Answer :
(A) Arete

Question 3.
Which landform is created by glacial deposition ?
(A) Cirque
(B) Hanging Valley
(C) Arete
(D) Moraine
Answer :
(D) Moraine

Question 4.
Cirques are
(A) Basins formed by river erosion
(B) Basins formed by wind erosion
(C) Vast amphitheatre like basin curved by glaciers
(D) None of these
Answer :
(C) Vast amphitheatre like basin curved by glaciers

Question 5.
Kettle holes are
(A) Depressions made by melting ice
(C) Depressions made by wind
(B) Depressions found at foot hills
(D) None of these
Answer :
(A) Depressions made by melting ice

Question 6.
Horn is created by
(A) One cirque
(B) Two cirques
(C) Cols
(D) Aretes
Answer :
(D) Aretes

Question 7.
Moraines are
(A) Depositions by rivers
(B) Depositions by glaciers
(C) Depositions by winds
(D) None of these
Answer :
(B) Depositions by glaciers

Question 8.
Drumlines are
(A) Boat-shaped depositions
(B) Narrow vallys
(C) Armchair shaped depression
(D) Pyramid peak
Answer :
(A) Boat-shaped depositions

Question 9.
Kames are
(A) Rift valleys
(B) Sand dunes
(C) Steep hills
(D) Long irregular hills formed by glacial deposition
Answer :
(D) Long irregular hills formed by glacial deposition

Question 10.
Outwash plain is
(A) Debris deposited by river
(B) Formed by silt deposition
(C) Debris deposited by ice at valley bottom
(D) None of these
Answer :
(C) Debris deposited by ice at valley bottom

Question 11.
Which landform is created by glacier?
(A) Inselberg
(B) Meander
(C) Pyramidal peak
(D) Gour
Answer :
(C) Pyramidal peak

Question 12.
Basket of eggs topography is related with
(A) Eskers
(B) Drumlins
(C) Outwash plains
(D) Corrie
Answer :
(B) Drumlins

Question 13.
Fjord coast is formed by
(A) Action of sea waves
(B) Submergence of river valleys
(C) Submergence of glacial valleys
(D) Action of wind
Answer :
(C) Submergence of glacial valleys

Question 14.
Hanging Valleys are formed by
(A) Mountain glaciers
(B) Continental glaciers
(C) Piedmont glaciers
(D) Coastal glaciers
Answer :
(A) Mountain glaciers

Question 15.
Glacial valley is
(A) I-shaped
(B) U-shaped
(C) V-shaped
(D) Y-shaped
Answer :
(B) U-shaped

Question 16.
The altitude over which snow never melts is called
(A) Snowline
(B) Glacier
(C) Tree line
(D) Cold wall
Answer :
(A) Snowline

Question 17.
Who commented – ‘A glacier is a mass of snow and ice that moves slowly over the land away from its placeof accumulation?
(A) Worcester
(B) Flint
(C) Lobeck
(D) Thombry
Answer :
(A) Worcester

Question 18.
The biggest glaciers on the earth’s surface are called
(A) Continental glaciers
(B) Cirque glaciers
(C) Niche glaciers
(D) Ice sheets
Answer :
(D) Ice sheets

Question 19.
Antarctica and greenland ice sheets are the examples of
(A) Mountain or valley glaciers
(B) Piedmont glaciers
(C) Continental glaciers
(D) Ice shelf
Answer :
(C) Continental glaciers

Question 20.
Which of the following is a floating thick ice sheet or ice cap attached to the coast?
(A) Ice field
(B) Ice shelf
(C) Valley glacier
(D) Cirque glacier
Answer :
(B) Ice shelf

Question 21.
The destruction of glacier front due to melting of ice consequently due to increase of temperature is called
(A) Advancement of glacier
(B) Stagnation of glacier
(C) Ablation of glacier
(D) None of these
Answer :
(C) Ablation of glacier

Question 22.
The glacier erodes its bed and side walls with the help of tools of erosion by the mechanism of
(A) Attrition
(B) Abrasion
(C) Corrosion
(D) Plucking
Answer :
(B) Abrasion

Question 23.
‘Head wall’ is a component of
(A) Tarn
(B) Nunatak
(C) U-shaped valley
(D) Cirque
Answer :
(D) Cirque

Question 24.
‘Corrie’ is the name of _____ in Scotland.
(A) U-shaped valley
(B) Arete
(C) Horn
(D) Cirque
Answer :
(D) Cirque

Question 25.
The line above which snow never meets in the high altitudes is called
(A) Snow line
(B) Glacier
(C) Iceberg
(D) Blow out
Answer :
(A) Snow line

Question 26.
______ part of an iceberg floats above the water surface
(A) 8 / 9
(B) 2 / 9
(C) 1 / 9
(D) 9
Answer :
(C) 1 / 9

Question 27.
Continental glaciers are seen is
(A) Himalayas
(B) Alps
(C) Andes
(D) Antarctica
Answer :
(D) Antarctica

Question 28.
The landform between two adjacent cirques is called
(A) Roches moutonnee
(B) Arets
(C) Pyramid peak
(D) Eskar
Answer :
(B) Arets

Question 29.
_____ is an example of an pyramidal peak
(A) Mont Blanc
(B) Matterhorn
(C) Mt. Abu
(D) Kanchenjunga
Answer :
(B) Matterhorn

Question 30.
The deepest fjord of the world is
(A) Dry galski fjord
(B) Geiranger fjord
(C) Soque fjord
(D) King oscar fjord
Answer :
(C) Soque fjord

Question 31.
Deep cracks on the surface of the mountain glacier are called
(A) Nunatak
(B) Creavasse
(C) Arete
(D) Cirque
Answer :
(B) Creavasse

Question 32.
A pyramidical peak formed due to recession and intersection of three or more cirques is called
(A) Horn
(B) Col
(C) Nunatak
(D) Arete
Answer :
(A) Horn

Question 33.
The higher peaks and mounds surrounded by ice from all sides are called
(A) Arete
(B) Nunatak
(C) Cirque
(D) Hom
Answer :
(B) Nunatak

Question 34.
Which glacial landform is formed by abrasion and plucking of step faults?
(A) Nunatak
(B) Roche Moutonne
(C) Grag and tail
(D) Glacial stairways
Answer :
(D) Glacial stairways

Question 35.
The rock debris carried by the glaciers are collectively called
(A) Tills
(B) Avalanches
(C) Glacial drifts
(D) Moraines
Answer :
(C) Glacial drifts

Question 36.
Which of the following terms refer to the depositional landforms of direct glacial origin?
(A) Moraines
(B) Talus
(C) Rock waste
(D) Regolith
Answer :
(A) Moraines

Question 37.
Which of the following are depressions in the outwash plains ?
(A) Kettles
(B) Cone Kames
(C) Beaded eskers
(D) Hummocks
Answer :
(A) Kettles

Question 38.
A tributary valley associated with the main glacial valley is called a
(A) Hanging valley
(B) V-shaped valley
(C) U-shaped valley
(D) None of these
Answer :
(A) Hanging valley

Question 39.
An armchain type of hollow cut into the mountain by a moving glacier is called a ______.
(A) U-shaped valley
(B) Roche moutonne
(C) Cirque
(D) Glacier lake
Answer :
(C) Cirque

Question 40.
Glacial troughs occupied by the sea are called
(A) Fjords
(B) Glacial groones
(C) Finger lakes
(D) None of these
Answer :
(A) Fjords

Question 41.
Fjord coasts are common in
(A) Norway
(B) Germany
(C) Sweden
(D) France
Answer :
(A) Norway

Fill in the blanks : 1 Mark

1. Glaciers flow faster in the ________ season.
2. The German word ‘berg’ means _______.
3. Bergschrunds are known as _______ in French.
4. The rock fragments of different sizes coming down by the melting of the glaciers is called _______.
5. The longest glacier of India is _______.
6. The Peterman glacier of greenland is a _______ glacier.
7. The ice line or snow line lies at the highest altitude in the _________ region.
8. The largest continental glacier of the word is the ______ glacier.
9. ________ is known as the land of fjords.
10. Corrie lakes are known as ______ in France.
11. The snow-less peaks in an ice covered regions are called _______.
12. Drumlins looks like _______.
13. The limit below which snow starts melting is called _______.
14. Eskar is a ________ landform formed by glacier.
15. Horizontal and parallel cracks or fractures found on the surface of a glacier are called _______.
Answer :
1. Summer
2. mountain
3. Rimaye
4. Boulder clay
5. Siachen
6. Continental
7. Equatorial
8. Lambort
9. Norway
10. Cirques
11. Nunatakes
12. inverted boats
13. snowline
14. Depositional
15. Crevasse

State True or False : 1 Mark

1. The period between two ice ages is called the non-ice age. [ ]
2. The outwash plain separated by a river is called the valley train. [ ]
3. Presently, the largest number of glaciers are found in Asia. [ ]
4. Eskers are formed by erosional work of glaciers. [ ]
5. Glaciers do not lie at the same altitude always. [ ]
6. The glacial valleys are U-shaped. [ ]
7. The floating blocks of ice in oceans are called snow lines. [ ]
8. The tongue-shaped part in front of a moving glacier is called a shout. [ ]
9. Matterhorn peak in the Alps is a pyramidical peak. [ ]
10. Small continental glaciers are known as glacier sheets. [ ]
11. Nunatakes are seen in polar region. [ ]
12. The submerged glacial valleys formed due to erosion by continental or mountain glaciers are called fjords. [ ]
13. The regions clustered with drumlines is also called ‘basket of eggs topagraphy’. [ ]
14. Waterfalls are formed from the meltwater of hanging valleys after deglaciation. [ ]
15. Altitude of snowline varies with latitudes. [ ]
Answer:
1. True
2. True
3. False
4. False
5. True
6. True
7. False
8. True
9. True
10. False
11. True
12. True
13. True
14. True
15. True

Answer in few words : 1 Mark

Question 1.
What is a crevasse?
Answer:
Cracks that develop on the surface of a glacier.

Question 2.
What is snow line?
Answer:
The altitude above which there is permanent snow lying throughout the year is known as the snow line.

Question 3.
What is a glacier?
Answer:
A glacier is a body of ice that flows downwards along the slope of the land due to gravity.

Question 4.
What is a snout ?
Answer:
The glacier’s downstream end is called snout.

Question 5.
What is iceberg ?
Answer:
Huge blocks of ice that break off from glaciers and fall into the sea are called icebergs.

Question 6.
Where do piedmont glaciers lie ?
Answer:
At the foot of the mountains.

Question 7.
Which is the world’s longest continental glacier ?
Answer:
Lambert glacier in Antarctica.

Question 8.
What are the main works of a glacier?
Answer:
Erosion, transportation and deposition.

Question 9.
How are moraines formed ?
Answer:
By glacial deposition.

Question 10.
What are kames?
Answer:
Rounded hillocks of sand and gravel formed due to glacial deposition.

Question 11.
How does a landform comprising of several drumlins look like?
Answer:
Basket of eggs topography.

Question 12.
What kind of a glacier is Siachen in India ?
Answer:
Mountain or valley glacier.

Question 13.
What are compaction of granular snow called ?
Answer:
Firm.

Question 14.
Which continent has the maximum number of glaciers ?
Answer:
Antarctica.

Question 15.
Name the largest valley glacier of the world ?
Answer:
Lambert.