Geography - Physical Features of India

 PHYSICAL FEATURES OF INDIA

1.      Describe the theory of plate tectonics.

A.     -Earth scientists have attempted to explain the formation of physical features with the help of some   theories based on certain evidences .

-One of the theory of the theory of plate tectonics .According to this theory, the crust of the earth has been formed out of seven major and some minor plates.

     

2.      Distinguish between Converging Plates and diverging Plates.

Converging Plates	Diverging Plates
a)       When tectonic plates move towards each other , they are called converging plates b)      When they move towards each other , they collide or crumble or one of them slides under the other c)      Converging plates cause folds.	a)      When tectonic plates move away from each other , they are termed as diverging plates b)      When they move away from each other they do not collide or crumble . c)      Diverging plates cause fractures in the crusts.

3.      Describe how the Himalyas were formed .

A.     The oldest landmass –the peninsular part , was a part of the Gondwana land .

The Gondwana land included India , Australia , South Africa , South America and Antarctica as one single land mass.

The convectional current split the crust into a number if pieces , thus leading to the drifting of the Indo –Australian plate after being separated from the Gondwana land , towards north.

The north ward drift resulted in the collision of the plate with the Eurasian plate .

Due to this collision , the sedimentary rocks in the Tethys were folded to form the mountain system of western Asia and Himalayas.

4.      How was the Great Northern plains of India formed ?

A.     -The formation of the Himalayas due to upliftment of sediments out of the Tethys Sea and subsidence of the northern flank of the Peninsular plateau resulted in the formation of a large basin.

-Over million of years this depression gradually got filled with alluvium deposited by the three major river system –the Indus, the Ganga and the Brahmaputra flowing from the Himalayas in the north.

-sediments were also deposited by the tributaries of these rivers rising from the mountains in the north as well as the peninsular plateau in its south .

-As a result , the fertile northern plain was formed

-As the Himalayas gained in height , the rivers became increasingly active in erosion .As a result , large amount of silt got deposited in the shrinking Tethys.

     5.    Name the major physiographic divisions of India

     A.   -The Himalayan mountains

            -The northern plains

            -The peninsular plateau

            -The Indian Desert

            -The coastal plains

            -The Islands

6.     Write a note on the Great Himalyan Mountains.Explain the features of the parallel ranges of the Himalayas .

A.    -The Himalayas are the loftiest and one of the most rugged mountain systems of the world .

        -the mountain ranges of the Himalayas run in a west –east direction from the Indus to the Brahmaputra , stretching along the entire northern boundary of India .

        -geologically they are young and structurally fold mountain system.

        -It covers a distance of about 24,00 kms.Their width varies from 400 km in Kashmir to 150 km in Arunachal Pradesh.

        -the Himalayas consists of three parallel ranges running from west to east .

        a) Himadri        b) Himachal      c) Siwaliks.

        HIMADRI

        -The northern most range is known as the Great or Inner Himalayas  or the Himadri.

        -It is the most continuous range consisting of the loftiest peaks .

        -It has an average height of 6000 mts.

        -It contains all the prominent Himalayan peaks.(Mt .Everest , Kanchenjunga , Makalu, Dhaulagiri,Nanga parbat, Nanda devi, Namcha Barwa)

        -The folds of the himadri are asymmetrical in nature.

        -It is perennially snow bound .

        HIMACHAL

        -The range lying to the south of the Himadri forms the most rugged mountain system and is know as Himachal or lesser Himalaya.

        -These ranges are mainly composed of highly compressed and altered rocks.

        -The altitude varies between 3700 and 4500 mts

        -The average width is 50 kms.

        -The Pir Panjal range , the Dhaula Dhar  and the Mahabharat ranges are important ranges .

        -The famous valley of Kashmir , the Kangra and the Kullu valley are located in this range.

        -This region is well known for its hill stations like-Mussoorie,  Nainital , Ranikhet etc.

       

        SHIWALIKS

        -The outer most range of the Himalayas is called the outer Himalayas or the shiwaliks.

        -They extent over a width of 10 -50 km.

        -The average height ranges between 900 and 1100 mts.

        -They are composed of unconsolidated sediments , gravel and alluvium brought down by the rivers .

        -The longitudinal valley lying between lesser Himalayas and the shiwaliks are known as Duns .

        Eg…Dehra Dun , Kotli dun and Patli Dun .

7.     Himalayas are also demarcated by the river valleys .Explain

A.    Himalayas are divided into four regions from west to east .These divisions are demarcated by river valleys.

        Punjab Himalayas : The part of Himalayas lying between Indus and satluj rivers is known as Punjab Himalayas or Kashmir Himalayas .

        Kumaon Himalayas : The part of Himalayas lying between  Satluj and Kali rivers .

        Nepal Himalayas : The part of Himalayas lying between   Kali and Tista rivers .

        Assam Himalayas: The part of Himalayas lying between  Tista and Dihang rivers .

8.     Write a brief note on the Purvanchal or the Eastern Hills.

A.    The Brahmaputra marks the eastern most boundary of the Himalayas .Beyond the Dihang gorge , the Himalayas bend towards south along the eastern boundary of India .They are known as the Eastern Hill or the Purvanchal.

        -These are mostly composed of sandstones which are sedimentary rocks .

        -They are covered with dense forests .

        -they run as parallel ranges and valleys .

-The Purvanchal comprises the Patkai hills, the Naga hills , Manipur hills and the mizo hills .

NORTHERN PLAIN

1.      Give an account of northern plains of India .

-The northern plain has been formed by the interplay of the three major river system –the Indus , the Ganga and the Brahmaputra  along with their tributaries.

-The plain is formed of alluvial soil. It is spread over 7 lakh sq .km.The plain is about 24oo km long and 240 to 320 km broad .

-It is a densely populated region ,with rich soil , adequate water supply and favorable climate.

-It is agriculturally a very productive part on india.

-the plain is marked with riverine features like –oxbow lakes , meanders , riverine islands.etc

-The northern plain is broadly divided into three sections namely-Punjab Plain , the Ganga plain , and the Brahmaputra plain

-the plain is further divided based on the relief into four –Bhabar , Terai, Bhangar , khaddar.

2.         Classify the plain on the basis of its location .

            -The northern plains are broadly divided into three sections:

            a) Punjab Plain:the western part of the northern plains is called the Punjab plain .It is formed by the river

Indus and its tributaries.Larger part of this plain lies in Pakistan.This section of the plain is dominated by the Doabs.

b)Ganga Plain:The Ganga plain extends between Ghaggar and Teesta river .It is spread over the states of North India , Haryana U.P, Bihar , Jharkhand and West Bengal.

c)Brahmaputra plain : To the east of the ganga plain lies the Brahmaputra plain , which covers the areas of Assam and Arunachal Pradesh .

3.         Classify northern plains on the basis of the variations in the relief features .

a)Bhabar: the river after decending from the mountain deposit pebbles in a narrow belt of about 8 to 16 km in width lying parallel to the slopes of the shiwaliks .It is known as bhabar .

All the streams disappear in this belt.

b)Terai:South of the bhabar , the streams and rivers re –emerge and create a wet , marshy and swampy area known as terai.This was a thickly forested region full of wildlife , now being cleared for agriculture.

c)Bhangar: The largest part of the northern plain is formed of older alluvium .They lie above the flood plain of the river and present a terrace like feature .These soils contain Kankar nodules in them .This part is known as Bhangar.

d)Khadar:The newer younger deposits of the flood plains are called khaddar .They are renewed almost every year and are therefore fertile .They are ideal for cultivation .

*Riverine island :In the lower course of the river , due to the gentle slope , the velocity of river decreases which results in the formation of riverine island .Eg.Majuli island in the Brahmaputra is the largest inhabited riverine island in the world.

THE PENINSULAR PLATEAU

1.      Describe  the peninsular plateau of India .

-         The peninsular plateau is a table land composed of the old crystalline , igneous and metamorphic rocks .

-         It is formed due to the breaking and drifting of the Gondwanaland .

-         The plateau has a broad and shallow valleys and rounded hills.

-         This plateau consists of two broad divisions-Central highlands and Deccan plateau.

-         One of the distinct features of the peninsular plateau is the black soil area known as the Deccan trap

2.      Write any four characteristics of the Central highlands.

-The part of the peninsular plateau lying to the north of the Narmada river , covering a major part of the Malwa plateau is known as the Central Highland .

-The vindhya range is bounded by the central highlands on the south and the Aravallis on the northwest ,further west it merges with the sandy desert of Rajasthan.

-the flow of the rivers draining this region , namely the Chambal , the sind , the Betwa and Ken is from south west to the north east ,which indicates the slope of the plateau.

-The central highland is wider in the west but narrower in the east .

-The eastward extension of this plateau is called bundelkhand and Baghelkhand .

-The chotanagpur plateau is the eastern most part of this plateau which is drained by Damodar river. 

    

3.      Write four features of the Deccan plateau .

-The deccan plateau is a triangular landmass that lies to the south of the river narmada .

-The Satpura range flanks its broad base in the north while the Mahadev , the Kaimur hills and the Maikal range form its eastward extension.

-The deccan plateau is higher in the west and slopes gently eastward.

 -The deccan plateau is bordered by the western Ghats on the west and by the eastern Ghats on the east .

-Its north –east extension is locally known as Meghalaya ,Karbi –Anglong plateau and north Chachar hills.It is separated by a fault from the Chota Nagpur Plateau .

-Three prominent hill ranges from the west to east are the Garo , Khasi and the Jaintia hills.

4.      Which part of peninsular plateau is called deccan Trap ?Give two features of Deccan trap.

-         The black soil area in the peninsular region is called the Deccan plateau .

-         This is formed by  volcanic activities , so the rocks are igneous .

-         These rocks have been denuded over time and are responsible for the formation of black soil.

5.      Write a brief note on the Aravalli hills.

-         The Aravalli hills lie on the western and northwestern margins of the peninsular plateau .

-         These are highly eroded hills and are found as broken hills.

-         They extend from Gujarat to Delhi in a southwest –northeast direction .

6.      Differentiate between the Western ghats and the Eastern Ghats .

Western Ghats	Eastern Ghats
They lie parallel to the western coast	The eastern ghats stretch from the Mahanadi valley to the Nilgiris in the south
They are continuous and can be crossed by the passes located in these ghats –thal , bhor and the pal ghat.	They are discontinuous and irregular and are dissected by rivers.
The average height is between 900 to 1600mts.	Their average height is 6oomts.
The highest peak is Anaimudi (2695mts)	The highest peak is Mahendragiri (1501)

7.      Contrast the relief of the Himalayan region with that of the Peninsular plateau.

-The Himalayan mountains have been formed by the folding process , while the peninsular plateau has been formed by the drifting of the Gondawanaland .

-The Himalayan mountain are made up of the sedimentary rocks, while the peninsular plateau contains igneous and the metamorphic rocks .

-The Himalayas are located in north India , whereas the plateau region is in south India .

-The Himalayas have glaciers , that provides perennial source of water the the northern rivers, while the plateau are the storehouse of minerals and help in industrialization

-The average height of the Himalayas are 6000 mts , while that of  plateau is 900mts.

THE INDIAN DESERT

1.      Write a short note on the Indian desert .

-The indian desert lies towards the western margins of the Aravalli hills .

-It is an undulating sandy plain covered with sand dunes .

-This region receives very low rainfall below 150mm per year.

-It has an arid climate with low vegetation .

-Streams appear during the rainy season and disappear into the sand during the dry season.

-Luni is the only large river in this region .

-Barchans cover larger areas .

THE COASTAL PLAIN

1.      Distinguish between the western and eastern coast.

Western  coastal plain	Eastern coastal plain
The western coast is sandwiched between the western ghats and the Arabian sea.	The eastern plain lies between the eastern ghats and the Bay of Bengal.
It is a narrow plain	It is wide and a leveled plain.
It consists of three sections – The northern part of the coast is called the Konkan , the central part is called the kannad plain and the southern part is called the Malabar coast .	This plain is called the northern circar in the north and Coromandel coast in the south .
The western coastal plain receives rainfall from the S.W monsoon.	The eastern coastal plain receives rainfall from the N.E monsoon.

THE ISLANDS

1.      Write a short note on the island groups of Indian island.

Lakshadweep Island:-

-Lakshadweep island lies close to the Malabar coast of kerala.

-It is composed of small coral islands.

-It covers an area of 32 sq.km.

-Kavaratti island is the administrative headquarters of Lakshadweep.

-The Pitti island which is  uninhabited ,has a bird sanctuary.

Andaman and Nicobar island

-These islands are located in the Bay of Bengal.

-They are  bigger in size and are more numerous and scattered.

-The entire island group is divided into two –Andaman in the north and Nicobar in the south .

-These island groups are of strategic importance for the country.

-there is great diversity of flora and fauna in this group of islands .

-These islands experience equatorial climate and has thick forest.

2.      How do different physical regions in India complement each other?

Each region complements the other and makes the country richer in its natural resources.

-The northern mountains are the major sources of water and forest wealth.

-The northern plains are the granaries of the country .They provided a base for early civilization .

-the plateau is a store house of minerals , which has played a crucial role in the industrialization .

-the coastal regions and island groups provide sites for fishing and port activities ,

Thus the diverse physical features of the land have immense future possibilities of development .

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