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You have already learnt earlier that Indiais a vast country with varied landforms.What kind of terrain do you live in? If

you live in the plains you are familiar with thevast stretches of plain land. In contrast, if youlive in hilly region, the rugged terrain withmountains and valleys are common features.In fact, our country has practically all majorphysical features of the earth i.e. mountains,plains, deserts, plateaus and islands. Youmust be wondering how these physicalfeatures have been formed. We will learn moreabout major physical features of India and howthey have been formed.

We find different types of rocks; some arevery hard like marble which has been used formaking the Taj Mahal, and some are very softlike soap stone which is used in making talcumpowder. The colour of soil varies from one placeto the other because soil is formed out ofdifferent types of rocks. Have you ever thoughtabout the causes of these variations? Most ofthese variations are caused due to differencesin rock formations.

India is a large landmass formed duringdifferent geological periods which has influencedher relief. Besides geological formations, anumber of processes such as weathering,erosion and deposition have created andmodified the relief to its present form.

Earth scientists have attempted to explainthe formation of physical features with the helpof some theories based on certain evidences.One such plausible theory is the “Theory of PlateTectonics”. According to this theory, the crust(upper part) of the earth has been formed out ofseven major and some minor plates. (Figure 2.2)

PHYSICAL FEATURES OF INDIA

The movement of the plates results in thebuilding up of stresses within the plates and thecontinental rocks above, leading to folding,faulting and volcanic activity. Broadly, theseplate movements are classified into threetypes(Figure 2.1). While some plates come towardseach other and form convergent boundary. Someplates move away from each other and formdivergent boundary. In the event of two platescoming together they may either collide andcrumble, or one may slide under the other. Attimes, they may also move horizontally past

PLATEPLATEPLATEPLATE

Divergent Boundary

Mantle

Convergent Boundary

PLATEPLATEPLATEPLATE

PLATEPLATE

PLATEPLATE

Mantle

Transform Boundary

Mantle

Mantle

Figure 2.1 : Plate Boundaries

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CONTEMPORARY INDIA8

each other and form transform boundary. Themovement of these plates have changed theposition and size of the continents over millionsof years. Such movements have also influencedthe evolution of the present landform featuresof India.

Gondwana land: It is the southern part of theancient super continent Pangea with Angara Landin the northern part.

The Himalayan uplift out of the Tethys seaand subsidence of the northern flank of thepeninsular plateau resulted in the formationof a large basin. In due course of time thisdepression, gradually got filled with depositionof sediments by the rivers flowing from themountains in the north and the peninsularplateau in the south. A flat land of extensivealluvial deposits led to the formation of thenorthern plains of India.

The land of India displays great physicalvariation. Geologically, the Peninsular Plateauconstitutes one of the ancient landmasses onthe earth’s surface. It was supposed to be oneof the most stable land blocks. The Himalayasand the Northern Plains are the most recentlandforms. From the view point of geology,Himalayan mountains form an unstable zone.The whole mountain system of Himalayarepresents a very youthful topography withhigh peaks, deep valleys and fast flowing rivers.The northern plains are formed of alluvial

Most volcanoes andearthquakes in the world are located at platemargins, but some do occur within the plates.

Figure 2.2 : World : Plate Margins

The oldest landmass, (the Peninsula part), wasa part of the Gondwana land. The Gondwanaland included India, Australia, South Africa,South America and Antarctica as one single landmass. The convectional currents split the crustinto a number of pieces, thus leading to the driftingof the Indo-Australian plate after being separatedfrom the Gondwana land, towards north. Thenorthward drift resulted in the collision of the platewith the much larger Eurasian Plate. Due to thiscollision, the sedimentary rocks which wereaccumulated in the geosyncline known as theTethys were folded to form the mountain systemof western Asia and Himalaya.

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PHYSICAL FEATURES OF INDIA 9

deposits. The peninsular plateau is composedof igneous and metamorphic rocks with gentlyrising hills and wide valleys.

MAJOR PHYSIOGRAPHIC DIVISIONS

The physical features of India can be groupedunder the following physiographic divisions(Figure 2.4):(1) The Himalayan Mountains(2) The Northern Plains(3) The Peninsular Plateau(4) The Indian Desert(5) The Coastal Plains(6) The Islands

The Himalayan Mountains

The Himalayas, geologically young andstructurally fold mountains stretch over the

Figure 2.3 : Himalayas

northern borders of India. These mountainranges run in a west-east direction from theIndus to the Brahmaputra. The Himalayasrepresent the loftiest and one of the mostrugged mountain barriers of the world. Theyform an arc, which covers a distance of about2,400 Km. Their width varies from 400 Kmin Kashmir to 150 Km in Arunachal Pradesh.The altitudinal variations are greater in theeastern half than those in the western half.The Himalaya consists of three parallelranges in its longitudinal extent. A numberof valleys lie between these ranges. Thenorthern most range is known as the Greator Inner Himalayas or the ‘Himadri’. It is themost continuous range consisting of theloftiest peaks with an average height of 6,000metres. It contains all the prominentHimalayan peaks.

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CONTEMPORARY INDIA10

Figure 2.4 : Relief

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Some Highest Peaks of the Himalayas

Peak Country Heightin metres

Mt. Everest Nepal 8848Kanchenjunga India 8598Makalu Nepal 8481Dhaulagiri Nepal 8172Nanga Parbat India 8126Annapurna Nepal 8078Nanda Devi India 7817Kamet India 7756Namcha Barwa India 7756Gurla Mandhata Nepal 7728

The folds of Great Himalayas areasymmetrical in nature. The core of this partof Himalayas is composed of granite. It isperennially snow bound, and a number ofglaciers descend from this range.

alluvium. The longitudinal valley lyingbetween lesser Himalaya and the Shiwaliks areknown as Duns. Dehra Dun, Kotli Dun andPatli Dun are some of the well-known Duns.

Besides the longitudinal divisions, theHimalayas have been divided on the basis ofregions from west to east. These divisionshave been demarcated by river valleys. Forexample, the part of Himalayas lying betweenIndus and Satluj has been traditionallyknown as Punjab Himalaya but it is alsoknown regionally as Kashmir and HimachalHimalaya from west to east respectively. Thepart of the Himalayas lying between Satlujand Kali rivers is known as KumaonHimalayas. The Kali and Tista riversdemarcate the Nepal Himalayas and the partlying between Tista and Dihang rivers isknown as Assam Himalayas. There areregional names also in these broadcategories. Find out some regional names ofthe Himalayas

The Brahmaputra marks the eastern mostboundary of the Himalayas. Beyond the Dihanggorge, the Himalayas bend sharply to the southand spread along the eastern boundary ofIndia. They are known as the Purvachal or theEastern hills and mountains. These hillsrunning through the north-eastern states aremostly composed of strong sandstones whichare sedimentary rocks. Covered with denseforests, they mostly run as parallel rangesand valleys. The Purvachal comprises the

• The names of the glaciers and passesthat lie in Great Himalayas• The name of the states where highest peaksare located.

• Location of Mussoorie, Nainital,Ranikhet from your atlas and also name the statewhere they are located.

Figure 2.5 : The Himalayas

The range lying to the south of the Himadriforms the most rugged mountain system andis known as Himachal or lesser Himalaya. Theranges are mainly composed of highlycompressed and altered rocks. The altitudevaries between 3,700 and 4,500 metres andthe average width is of 50 Km. While the PirPanjal range forms the longest and the mostimportant range, the Dhaula Dhar and theMahabharat ranges are also prominent ones.This range consists of the famous valley ofKashmir, the Kangra and Kullu Valley inHimachal Pradesh. This region is well knownfor its hill stations.

The outer most range of the Himalayas iscalled the Shiwaliks. They extend over a widthof 10-50 Km and have an altitude varyingbetween 900 and 1100 metres. These rangesare composed of unconsolidated sedimentsbrought down by rivers from the mainHimalayan ranges located farther north. Thesevalleys are covered with thick gravel and

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Patkai hills, the Naga hills, Manipur hills andthe Mizo hills.

The Northern Plain

The northern plain has been formed by theinterplay of the three major river systems,namely– the Indus, the Ganga and theBrahmaputra along with their tributaries. Thisplain is formed of alluvial soil. The depositionof alluvium in a vast basin lying at the foothillsof the Himalaya over millions of years, formedthis fertile plain. It spreads over an area of 7lakh sq. km. The plain being about 2400 Kmlong and 240 to 320 Km broad, is a denselypopulated physiographic division. With a richsoil cover combined with adequate watersupply and favourable climate it isagriculturally a very productive part of India.

The rivers coming from northernmountains are involved in depositional work.In the lower course, due to gentle slope, thevelocity of the river decreases which results inthe formation of riverine islands.

The rivers in their lower course split intonumerous channels due to the deposition of silt.These channels are known as distributaries.

The Northern Plain is broadly divided intothree sections. The Western part of the NorthernPlain is referred to as the Punjab Plains.Formed by the Indus and its tributaries, thelarger part of this plain lies in Pakistan. TheIndus and its tributaries–the Jhelum, theChenab, the Ravi, the Beas and the Satlujoriginate in the Himalaya. This section of theplain is dominated by the doabs.

Figure 2.7 : The Northern Plains

Majuli, in the BrahmaputraRiver is the largest inhabited riverine island in theworld.

Figure 2.6 : Mizo Hills

‘Doab’ is made up of twowords- ‘do’ meaning two and ‘ab’ meaning water.Similarly ‘Punjab’ is also made up two words- ‘Punj’meaning five and ‘ab’ meaning water.

The Ganga plain extends between Ghaggarand Teesta rivers. It is spread over the states ofNorth India, Haryana, Delhi, U.P., Bihar, partlyJharkhand and West Bengal to its East,particularly in Assam lies the Brahmaputra plain.

The northern plains are generally deseribedas flat land with no variations in its relief. It isnot true. These vast plains also have diverserelief features. According to the variations inrelief features, the Northern plains can bedivided into four regions. The rivers, afterdescending from the mountains depositpebbles in a narrow belt of about 8 to 16 kmin width lying parallel to the slopes of theShiwaliks. It is known as bhabar. All thestreams disappear in this bhabar belt. Southof this belt, the streams and rivers re-emergeand create a wet, swampy and marshy regionknown as terai. This was a thickly forestedregion full of wildlife. The forests have beencleared to create agricultural land and to settlemigrants from Pakistan after partition. LocateDudhwa National Park in this region.

The largest part of the northern plain isformed of older alluvium. They lie above theflood plains of the rivers and present a terracelike feature. This part is known as bhangar.

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The Deccan Plateau is a triangular landmassthat lies to the south of the river Narmada. TheSatpura range flanks its broad base in the northwhile the Mahadev, the Kaimur hills and theMaikal range form its eastern extensions. Locatethese hills and ranges in the physical map ofIndia. The Deccan Plateau is higher in the westand slopes gently eastwards. An extension of thePlateau is also visible in the northeast– locallyknown as the Meghalaya, Karbi-Anglong Plateauand North Cachar Hills. It is separated by afault from the Chotanagpur Plateau. ThreeProminent hill ranges from the west to east arethe Garo, the Khasi and the Jaintia Hills.

The Western Ghats and the Eastern Ghatsmark the western and the eastern edges of theDeccan Plateau respectively. Western Ghats lieparallel to the western coast. They are continuousand can be crossed through passes only. Locatethe Thal, Bhor and the Pal Ghats in the Physicalmap of India.

The Western Ghats are higher than theEastern Ghats. Their average elevation is 900–1600 metres as against 600 metres of theEastern Ghats. The Eastern Ghats stretch fromthe Mahanadi Valley to the Nigiris in the south.The Eastern Ghats are discontinuous andirregular and dissected by rivers draining intothe Bay of Bengal. The Western Ghats causeorographic rain by facing the rain bearing moistwinds to rise along the western slopes of theGhats. The Western Ghats are known bydifferent local names. The height of the WesternGhats progressively increases from north tosouth. The highest peaks include the AnaiMudi (2,695metres) and the Doda Betta (2,637metres). Mahendragiri (1,501 metres) is thehighest peak in the Eastern Ghats. ShevroyHills and the Javadi Hills are located to thesoutheast of the Eastern Ghats. Locate thefamous hill stations of Udagamandalam,popularly known as Ooty and the Kodaikanal.

One of the distinct features of the peninsularplateau is the black soil area known as DeceanTrap. This is of volcanic origin hence the rocksare igneous. Actually these rocks havedenuded over time and are responsible for theformation of black soil. The Aravali Hills lie onthe western and northwestern margins of the

The soil in this region contains calcareousdeposits locally known as kankar. The newer,younger deposits of the flood plains are calledkhadar. They are renewed almost every yearand so are fertile, thus, ideal for intensiveagriculture.

The Peninsular Plateau

The Peninsular plateau is a tablelandcomposed of the old crystalline, igneous andmetamorphic rocks. It was formed due to thebreaking and drifting of the Gondwana landand thus, making it a part of the oldestlandmass. The plateau has broad and shallowvalleys and rounded hills. This plateauconsists of two broad divisions, namely, theCentral Highlands and the Deccan Plateau.The part of the Peninsular plateau lying tothe north of the Narmada river covering amajor area of the Malwa plateau is known asthe Central Highlands. The Vindhyan rangeis bounded by the Central Highlands on thesouth and the Aravalis on the northwest. Thefurther westward extension gradually mergeswith the sandy and rocky desert of Rajasthan.The flow of the rivers draining this region,namely the Chambal, the Sind, the Betwa andKen is from southwest to northeast, thusindicating the slope. The Central Highlandsare wider in the west but narrower in the east.The eastward extensions of this plateau arelocally known as the Bundelkhand andBaghelkhand. The Chotanagpur plateaumarks the further eastward extension,drained by the Damodar river.

Figure 2.8 : A waterfall in Chotanagpur Plateau

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peninsular plateau. These are highly erodedhills and are found as broken hills. They extendfrom Gujarat to Delhi in a southwest-northeastdirection.

The Indian Desert

The Indian desest lies towards the westernmargins of the Aravali Hills. It is an undulatingsandy plain covered with sand dunes. Thisregion receives very low rainfall below 150 mmper year. It has arid climate with lowvegetation cover. Streams appear during therainy season. Soon after they disappear intothe sand as they do not have enough water toreach the sea. Luni is the only large river inthis region.

The plains along the Bay of Bengal are wideand level. In the northern part, it is referred toas the Northern Circar, while the southern partis known as the Coromandel Coast. Largerivers such as the Mahanadi, the Godavari, theKrishna and the Kaveri have formed extensivedelta on this coast. Lake Chilika is animportant feature along the eastern coast.

The Chilika Lake is thelargest salt water lake in India. It lies in the stateof Orissa, to the south of the Mahanadi delta.

The Islands

You have already seen that India has a vast mainland. Besides this, the country has also two groupsof islands. Can you identify these island groups?

Figure 2.10 : The Coastal Plains

Figure 2.11 : An Island

Figure 2.9 : The Indian Desert

Barchans (crescent shaped dunes) coverlarger areas but longitudinal dunes becomemore prominent near the Indo-Pakistanboundary. If you visit Jaisalmer, you may goto see a group of barchans.

The Coastal Plains

The Peninsular plateau is flanked by stretchof narrow coastal strips, running along theArabian Sea on the west and the Bay of Bengalon the east. The western coast, sandwichedbetween the Western Ghats and the ArabianSea, is a narrow plain. It consists of threesections. The northern part of the coast is calledthe Konkan (Mumbai – Goa), the central stretchis called the Kannad Plain while the southernstretch is referred to as the Malabar coast.

Locate the Lakshadweep Islands grouplying close to the Malabar coast of Kerala. Thisgroup of islands is composed of small coralisalnds. Earlier they were known as Laccadive,Minicoy and Amindive. In 1973 these were

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Corals

Coral polyps are short-lived microscopicorganisms, which live in colonies. They flourishin shallow, mud free and warm waters. Theysecrete calcium carbonate. The coral secretionand their skeletons from coral deposits in theform of reefs:. they are mainly of three kinds:barrier reef. fringing reef and atolls. The GreatBarrier Reef of Australia is a good example of thefirst kind of coral reefs. Atolls are circular orhorse shoe shaped coral reefs.

named as Lakshadweep. It covers small areaof 32 sq km. Kavaratti island is theadministrative headquarters of Lakshadweep.This island group has great diversity of floraand fauna. The Pitti island, which isuninhabited, has a bird sanctuary.

starategic importance for the country. Thereis great diversity of flora and fauna in thisgroup of islands too. These islands lie close toequator and experience equatorial climate andhas thick forest cover.

1. Choose the right answer from the four alternatives given below.(i) A landmass bounded by sea on three sides is referred to as

(a) Coast (c) Peninsula(b) Island (d) none of the above

(ii) Mountain ranges in the eastern part of India forming its boundary withMyanmar are collectively called as(a) Himachal (c) Purvachal(b) Uttarakhand (d) none of the above

(iii) The western coastal strip, south of Goa is referred to as(a) Coromandel (c) Kannad(b) Konkan (d) Northern Circar

(iv) The highest peak in the Eastern Ghats is(a) Anai Mudi (c) Mahendragiri(b) Kanchenjunga (d) Khasi

2 Answer the following questions briefly.(i) What are tectonic plates?(ii) Which continents of today were part of the Gondwana land?

Now you see the elongated chain of islandslocated in the Bay of Bengal extending fromnorth to south. These are Andaman andNicobar islands. They are bigger in size andare more numerous and scattered. The entiregroup of islands is divided into two broadcategories – The Andaman in the north andthe Nicobar in the south. It is believed that theseislands are an elevated portion of submarinemountains. These island groups are of great

India’s only active volcano isfound on Barren island in Andaman and Nicobargroup of Islands.

A detailed account of the differentphysiographic units highlights the uniquefeatures of each region. It would, however,be clear that each region complements theother and makes the country richer in itsnatural resources. The mountains are themajor sources of water and forest wealth.The northern plains are the granaries of thecountry. They provide the base for earlycivilisations. The plateau is a storehouseof minerals, which has played a crucial rolein the industrialisation of the country. Thecoastal region and island groups providesites for fishing and port activities. Thus,the diverse physical features of the landhave immense future possibil it ies ofdevelopment.

EXERCISE

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(iii) What is the bhabar?(iv) Name the three major divisions of the Himalayas from north to south.(v) Which plateau lies between the Aravali and the Vindhyan ranges?(vi) Name the island group of India having coral origin.

3. Distinguish between(i) Converging and diverging tectonic plates(ii) Bhangar and Khadar(iii) Western Ghats and Eastern Ghats

4. Describe how the Himalayas were formed.5. Which are the major physiographic divisions of India? Contrast the relief of the

Himalayan region with that of the Peninsular plateau.6. Give an account of the Northern Plains of India.7. Write short notes on the following.

(i) The Indian Desert(ii) The Central Highlands

(iii) The Island groups of India

MAP SKILLS

On an outline map of India show the following.(i) Mountain and hill ranges – the Karakoram, the Zaskar, the Patkai Bum, the

Jaintia, the Vindhya range, the Aravali, and the Cardamom hills.(ii) Peaks – K2, Kanchenjunga, Nanga Parbat and the Anai Mudi.(iii) Plateaus, Chotanagpur and Malwa(iv) The Indian Desert, Western Ghats, Lakshadweep Islands

PROJECT/ACTIVITY

Locate the peaks, passes, ranges, plateaus, hills, and duns hidden in the puzzle.Try to find where these features are located. You may start your search horizontally,vertically or diagonally.

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