Geography Contemporary India PDF

PHYSICAL F EATURES OF INDIA 2 d Y ou have already learnt earlier...

PHYSICAL F EATURES OF INDIA 2 d Y ou have already learnt earlier that India The movement of the plates results in the he is a vast country with varied landforms. building up of stresses within the plates and the What kind of terrain do you live in? If continental rocks above, leading to folding, you live in the plains you are familiar with the faulting and volcanic activity. Broadly, these vast stretches of plain land. In contrast, if you plate movements are classified into three is live in hilly region, the rugged terrain with types(Figure 2.1). While some plates come towards mountains and valleys are common features. each other and form convergent boundary. Some In fact, our country has practically all major plates move away from each other and form bl physical features of the earth i.e. mountains, divergent boundary. In the event of two plates plains, deserts, plateaus and islands. You coming together they may either collide and must be wondering how these physical crumble, or one may slide under the other. At features have been formed. We will learn more pu times, they may also move horizontally past about major physical features of India and how they have been formed. be T We find different types of rocks; some are very hard like marble which has been used for re making the Taj Mahal, and some are very soft o R like soap stone which is used in making talcum powder. The colour of soil varies from one place to the other because soil is formed out of tt E different types of rocks. Have you ever thought PLATE PLATE about the causes of these variations? Most of Mantle Convergent Boundary these variations are caused due to differences C in rock formations. India is a large landmass formed during different geological periods which has influenced no N her relief. Besides geological formations, a number of processes such as weathering, erosion and deposition have created and PLATE PLATE modified the relief to its present form. © Mantle Earth scientists have attempted to explain Divergent Boundary the formation of physical features with the help of some theories based on certain evidences. PLATE One such plausible theory is the “Theory of Plate Mantle PLATE Mantle Tectonics”. According to this theory, the crust Transform Boundary (upper part) of the earth has been formed out of seven major and some minor plates. (Figure 2.2) Figure 2.1 : Plate Boundaries  d he is bl Figure 2.2 : World : Plate Margins pu each other and form transform boundary. The Gondwana land: It is the southern part of the movement of these plates have changed the ancient super continent Pangea with Angara Land position and size of the continents over millions in the northern part. be T of years. Such movements have also influenced The Himalayan uplift out of the Tethys sea re the evolution of the present landform features and subsidence of the northern flank of the o R of India. peninsular plateau resulted in the formation of a large basin. In due course of time this Most volcanoes and depression, gradually got filled with deposition tt E earthquakes in the world are located at plate of sediments by the rivers flowing from the margins, but some do occur within the plates. mountains in the north and the peninsular C plateau in the south. A flat land of extensive The oldest landmass, (the Peninsula part), was alluvial deposits led to the formation of the a part of the Gondwana land. The Gondwana northern plains of India. land included India, Australia, South Africa, no N The land of India displays great physical South America and Antarctica as one single land variation. Geologically, the Peninsular Plateau mass. The convectional currents split the crust constitutes one of the ancient landmasses on into a number of pieces, thus leading to the drifting the earth’s surface. It was supposed to be one of the Indo-Australian plate after being separated © of the most stable land blocks. The Himalayas from the Gondwana land, towards north. The and the Northern Plains are the most recent northward drift resulted in the collision of the plate landforms. From the view point of geology, with the much larger Eurasian Plate. Due to this Himalayan mountains form an unstable zone. collision, the sedimentary rocks which were The whole mountain system of Himalaya accumulated in the geosyncline known as the represents a very youthful topography with Tethys were folded to form the mountain system high peaks, deep valleys and fast flowing rivers. of western Asia and Himalaya. The northern plains are formed of alluvial 8 CONTEMPORARY INDIA  deposits. The peninsular plateau is composed northern borders of India. These mountain of igneous and metamorphic rocks with gently ranges run in a west-east direction from the rising hills and wide valleys. Indus to the Brahmaputra. The Himalayas represent the loftiest and one of the most MAJOR PHYSIOGRAPHIC D IVISIONS rugged mountain barriers of the world. They form an arc, which covers a distance of about The physical features of India can be grouped 2,400 Km. Their width varies from 400 Km under the following physiographic divisions in Kashmir to 150 Km in Arunachal Pradesh. (Figure 2.4): The altitudinal variations are greater in the (1) The Himalayan Mountains eastern half than those in the western half. (2) The Northern Plains The Himalaya consists of three parallel d (3) The Peninsular Plateau ranges in its longitudinal extent. A number (4) The Indian Desert of valleys lie between these ranges. The (5) The Coastal Plains he northern most range is known as the Great (6) The Islands or Inner Himalayas or the ‘Himadri’. It is the most continuous range consisting of the The Himalayan Mountains loftiest peaks with an average height of 6,000 The Himalayas, geologically young and metres. It contains all the prominent is structurally fold mountains stretch over the Himalayan peaks. bl pu be T re o R tt E C no N © Figure 2.3 : Himalayas PHYSICAL FEATURES OF INDIA 9  d he is bl pu be T re o R tt E C no N © Figure 2.4 : Relief 10 CONTEMPORARY INDIA  Some Highest Peaks of the Himalayas alluvium. The longitudinal valley lying Peak Country Height between lesser Himalaya and the Shiwaliks are in metres known as Duns. Dehra Dun, Kotli Dun and Mt. Everest Nepal 8848 Patli Dun are some of the well-known Duns. Kanchenjunga India 8598 Makalu Nepal 8481 Dhaulagiri Nepal 8172 Nanga Parbat India 8126 Annapurna Nepal 8078 Nanda Devi India 7817 Kamet India 7756 Namcha Barwa India 7756 d Gurla Mandhata Nepal 7728 The folds of Great Himalayas are he asymmetrical in nature. The core of this part of Himalayas is composed of granite. It is perennially snow bound, and a number of glaciers descend from this range. Figure 2.5 : The Himalayas is The names of the glaciers and passes Besides the longitudinal divisions, the that lie in Great Himalayas The name of the states where highest peaks Himalayas have been divided on the basis of bl are located. regions from west to east. These divisions have been demarcated by river valleys. For The range lying to the south of the Himadri example, the part of Himalayas lying between pu forms the most rugged mountain system and Indus and Satluj has been traditionally is known as Himachal or lesser Himalaya. The known as Punjab Himalaya but it is also ranges are mainly composed of highly known regionally as Kashmir and Himachal be T compressed and altered rocks. The altitude Himalaya from west to east respectively. The varies between 3,700 and 4,500 metres and re the average width is of 50 Km. While the Pir part of the Himalayas lying between Satluj o R Panjal range forms the longest and the most and Kali rivers is known as Kumaon important range, the Dhaula Dhar and the Himalayas. The Kali and Tista rivers Mahabharat ranges are also prominent ones. demarcate the Nepal Himalayas and the part tt E This range consists of the famous valley of lying between Tista and Dihang rivers is Kashmir, the Kangra and Kullu Valley in known as Assam Himalayas. There are Himachal Pradesh. This region is well known regional names also in these broad C for its hill stations. categories. Find out some regional names of the Himalayas no N Location of Mussoorie, Nainital, The Brahmaputra marks the eastern most Ranikhet from your atlas and also name the state boundary of the Himalayas. Beyond the Dihang where they are located. gorge, the Himalayas bend sharply to the south The outer most range of the Himalayas is and spread along the eastern boundary of © called the Shiwaliks. They extend over a width India. They are known as the Purvachal or the of 10-50 Km and have an altitude varying Eastern hills and mountains. These hills between 900 and 1100 metres. These ranges running through the north-eastern states are are composed of unconsolidated sediments mostly composed of strong sandstones which brought down by rivers from the main are sedimentary rocks. Covered with dense Himalayan ranges located farther north. These forests, they mostly run as parallel ranges valleys are covered with thick gravel and and valleys. The Purvachal comprises the PHYSICAL FEATURES OF INDIA 11  Majuli, in the Brahmaputra River is the largest inhabited riverine island in the world. The rivers in their lower course split into numerous channels due to the deposition of silt. These channels are known as distributaries. The Northern Plain is broadly divided into three sections. The Western part of the Northern Plain is referred to as the Punjab Plains. Formed by the Indus and its tributaries, the d Figure 2.6 : Mizo Hills larger part of this plain lies in Pakistan. The Patkai hills, the Naga hills, Manipur hills and Indus and its tributaries–the Jhelum, the he the Mizo hills. Chenab, the Ravi, the Beas and the Satluj originate in the Himalaya. This section of the The Northern Plain plain is dominated by the doabs. The northern plain has been formed by the is interplay of the three major river systems, ‘Doab’ is made up of two namely– the Indus, the Ganga and the words- ‘do’ meaning two and ‘ab’ meaning water. Brahmaputra along with their tributaries. This Similarly ‘Punjab’ is also made up two words- ‘Punj’ bl plain is formed of alluvial soil. The deposition meaning five and ‘ab’ meaning water. of alluvium in a vast basin lying at the foothills of the Himalaya over millions of years, formed The Ganga plain extends between Ghaggar and Teesta rivers. It is spread over the states of pu this fertile plain. It spreads over an area of 7 lakh sq. km. The plain being about 2400 Km North India, Haryana, Delhi, U.P., Bihar, partly long and 240 to 320 Km broad, is a densely Jharkhand and West Bengal to its East, be T populated physiographic division. With a rich particularly in Assam lies the Brahmaputra plain. soil cover combined with adequate water The northern plains are generally deseribed re supply and favourable climate it is as flat land with no variations in its relief. It is o R agriculturally a very productive part of India. not true. These vast plains also have diverse relief features. According to the variations in relief features, the Northern plains can be tt E divided into four regions. The rivers, after descending from the mountains deposit pebbles in a narrow belt of about 8 to 16 km C in width lying parallel to the slopes of the Shiwaliks. It is known as bhabar. All the streams disappear in this bhabar belt. South no N of this belt, the streams and rivers re-emerge and create a wet, swampy and marshy region known as terai. This was a thickly forested region full of wildlife. The forests have been © cleared to create agricultural land and to settle Figure 2.7 : The Northern Plains migrants from Pakistan after partition. Locate The rivers coming from northern Dudhwa National Park in this region. mountains are involved in depositional work. The largest part of the northern plain is In the lower course, due to gentle slope, the formed of older alluvium. They lie above the velocity of the river decreases which results in flood plains of the rivers and present a terrace the formation of riverine islands. like feature. This part is known as bhangar. 12 CONTEMPORARY INDIA  The soil in this region contains calcareous The Deccan Plateau is a triangular landmass deposits locally known as kankar. The newer, that lies to the south of the river Narmada. The younger deposits of the flood plains are called Satpura range flanks its broad base in the north khadar. They are renewed almost every year while the Mahadev, the Kaimur hills and the and so are fertile, thus, ideal for intensive Maikal range form its eastern extensions. Locate agriculture. these hills and ranges in the physical map of India. The Deccan Plateau is higher in the west The Peninsular Plateau and slopes gently eastwards. An extension of the Plateau is also visible in the northeast– locally The Peninsular plateau is a tableland known as the Meghalaya, Karbi-Anglong Plateau composed of the old crystalline, igneous and and North Cachar Hills. It is separated by a d metamorphic rocks. It was formed due to the fault from the Chotanagpur Plateau. Three breaking and drifting of the Gondwana land Prominent hill ranges from the west to east are and thus, making it a part of the oldest he the Garo, the Khasi and the Jaintia Hills. landmass. The plateau has broad and shallow The Western Ghats and the Eastern Ghats valleys and rounded hills. This plateau mark the western and the eastern edges of the consists of two broad divisions, namely, the Deccan Plateau respectively. Western Ghats lie Central Highlands and the Deccan Plateau. parallel to the western coast. They are continuous is The part of the Peninsular plateau lying to and can be crossed through passes only. Locate the north of the Narmada river covering a the Thal, Bhor and the Pal Ghats in the Physical major area of the Malwa plateau is known as map of India. bl the Central Highlands. The Vindhyan range The Western Ghats are higher than the is bounded by the Central Highlands on the Eastern Ghats. Their average elevation is 900– south and the Aravalis on the northwest. The 1600 metres as against 600 metres of the pu further westward extension gradually merges Eastern Ghats. The Eastern Ghats stretch from with the sandy and rocky desert of Rajasthan. the Mahanadi Valley to the Nigiris in the south. The flow of the rivers draining this region, The Eastern Ghats are discontinuous and be T namely the Chambal, the Sind, the Betwa and irregular and dissected by rivers draining into Ken is from southwest to northeast, thus the Bay of Bengal. The Western Ghats cause re o R indicating the slope. The Central Highlands orographic rain by facing the rain bearing moist are wider in the west but narrower in the east. winds to rise along the western slopes of the The eastward extensions of this plateau are Ghats. The Western Ghats are known by tt E locally known as the Bundelkhand and different local names. The height of the Western Baghelkhand. The Chotanagpur plateau Ghats progressively increases from north to marks the further eastward extension, south. The highest peaks include the Anai C drained by the Damodar river. Mudi (2,695metres) and the Doda Betta (2,637 metres). Mahendragiri (1,501 metres) is the highest peak in the Eastern Ghats. Shevroy no N Hills and the Javadi Hills are located to the southeast of the Eastern Ghats. Locate the famous hill stations of Udagamandalam, popularly known as Ooty and the Kodaikanal. © One of the distinct features of the peninsular plateau is the black soil area known as Decean Trap. This is of volcanic origin hence the rocks are igneous. Actually these rocks have denuded over time and are responsible for the formation of black soil. The Aravali Hills lie on Figure 2.8 : A waterfall in Chotanagpur Plateau the western and northwestern margins of the PHYSICAL FEATURES OF INDIA 13  peninsular plateau. These are highly eroded hills and are found as broken hills. They extend from Gujarat to Delhi in a southwest-northeast direction. The Indian Desert The Indian desest lies towards the western margins of the Aravali Hills. It is an undulating sandy plain covered with sand dunes. This region receives very low rainfall below 150 mm d per year. It has arid climate with low vegetation cover. Streams appear during the rainy season. Soon after they disappear into he Figure 2.10 : The Coastal Plains the sand as they do not have enough water to reach the sea. Luni is the only large river in The plains along the Bay of Bengal are wide this region. and level. In the northern part, it is referred to as the Northern Circar, while the southern part is is known as the Coromandel Coast. Large rivers such as the Mahanadi, the Godavari, the Krishna and the Kaveri have formed extensive bl delta on this coast. Lake Chilika is an important feature along the eastern coast. pu The Chilika Lake is the largest salt water lake in India. It lies in the state of Orissa, to the south of the Mahanadi delta. be T The Islands re o R Figure 2.9 : The Indian Desert You have already seen that India has a vast main land. Besides this, the country has also two groups Barchans (crescent shaped dunes) cover of islands. Can you identify these island groups? tt E larger areas but longitudinal dunes become more prominent near the Indo-Pakistan boundary. If you visit Jaisalmer, you may go C to see a group of barchans. no N The Coastal Plains The Peninsular plateau is flanked by stretch of narrow coastal strips, running along the Arabian Sea on the west and the Bay of Bengal © on the east. The western coast, sandwiched Figure 2.11 : An Island between the Western Ghats and the Arabian Sea, is a narrow plain. It consists of three Locate the Lakshadweep Islands group sections. The northern part of the coast is called lying close to the Malabar coast of Kerala. This the Konkan (Mumbai – Goa), the central stretch group of islands is composed of small coral is called the Kannad Plain while the southern isalnds. Earlier they were known as Laccadive, stretch is referred to as the Malabar coast. Minicoy and Amindive. In 1973 these were 14 CONTEMPORARY INDIA  named as Lakshadweep. It covers small area starategic importance for the country. There of 32 sq km. Kavaratti island is the is great diversity of flora and fauna in this administrative headquarters of Lakshadweep. group of islands too. These islands lie close to This island group has great diversity of flora equator and experience equatorial climate and and fauna. The Pitti island, which is has thick forest cover. uninhabited, has a bird sanctuary. India’s only active volcano is Corals found on Barren island in Andaman and Nicobar Coral polyps are short-lived microscopic group of Islands. organisms, which live in colonies. They flourish d in shallow, mud free and warm waters. They secrete calcium carbonate. The coral secretion A detailed account of the different and their skeletons from coral deposits in the physiographic units highlights the unique he form of reefs:. they are mainly of three kinds: barrier reef. fringing reef and atolls. The Great features of each region. It would, however, Barrier Reef of Australia is a good example of the be clear that each region complements the first kind of coral reefs. Atolls are circular or other and makes the country richer in its horse shoe shaped coral reefs. natural resources. The mountains are the is major sources of water and forest wealth. Now you see the elongated chain of islands The northern plains are the granaries of the located in the Bay of Bengal extending from country. They provide the base for early bl north to south. These are Andaman and civilisations. The plateau is a storehouse Nicobar islands. They are bigger in size and of minerals, which has played a crucial role are more numerous and scattered. The entire in the industrialisation of the country. The pu group of islands is divided into two broad coastal region and island groups provide categories – The Andaman in the north and sites for fishing and port activities. Thus, the Nicobar in the south. It is believed that these the diverse physical features of the land be T islands are an elevated portion of submarine have immense future possibilities of mountains. These island groups are of great development. re o R EXERCISE tt E 1. Choose the right answer from the four alternatives given below. (i) A landmass bounded by sea on three sides is referred to as C (a) Coast (c) Peninsula (b) Island (d) none of the above (ii) Mountain ranges in the eastern part of India forming its boundary with no N Myanmar 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? PHYSICAL FEATURES OF INDIA 15  (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. d 6. Give an account of the Northern Plains of India. 7. Write short notes on the following. he (i) The Indian Desert (ii) The Central Highlands (iii) The Island groups of India is MAP SKILLS On an outline map of India show the following. (i) Mountain and hill ranges – the Karakoram, the Zaskar, the Patkai Bum, the bl 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 pu (iv) The Indian Desert, Western Ghats, Lakshadweep Islands PROJECT/ACTIVITY be T Locate the peaks, passes, ranges, plateaus, hills, and duns hidden in the puzzle. re Try to find where these features are located. You may start your search horizontally, o R vertically or diagonally. tt E C no N © 16 CONTEMPORARY INDIA