Physical features of India.pptx

Ppt for class 9 chapter 2

1. ARMY PUBLIC SCHOOL UDHAMPUR WELCOME TO ONLINE CLASS Topic: PHYSICAL FEATURES OF INDIA Prepared by: Parvaiz Ahmad Malik PGT Economics

2. Objectives Knowing about India’s Relief, Major Physiographic Units and Structure. To understand the major landforms, features and the underlying geological structure Their association with different rocks and minerals as well as nature of soil types.

3. Some Facts that Matter 1.India is a large landmass formed during different geological periods by processes such as Weathering, Erosion and deposition have also influenced its relief. 2.According to the Theory of Plate tectonics developed in 1960s by Alfred Wegener , the crust or the upper part of the earth has been formed out of seven major and some minor plates. 3. The theory of plate tectonics states that the Earth’s solid outer crust, the lithosphere, is separated into plates that move over the asthenosphere, the molten upper portion of the mantle. Born :  1 November 1880,  Berlin, Germany Died :  November 1930,  Nationality :  German Full name :  Alfred Lothar Wegener

4. 4. There are two other theories as well i ) Continental drift theory ii) Seafloor spreading 5 .These plate movements are of Three types – convergent boundary, Divergent Boundary and transform Boundary . 6 .The oldest landmass was a part of the Gondawana land which includes India, Australia, South Africa, South America and Antarctica as one single landmass.

5. Continental drift theory Continental drift was a theory that explained how continents shift position on Earth's surface. Set forth in 1912 by Alfred Wegener, a geophysicist and meteorologist continental drift also explained why look-alike animal and plant fossils, and similar rock formations, are found on different continents. 

6. Seafloor spreading Seafloor spreading is the mechanism by which new seafloor lithosphere is constantly being created at mid-ocean ridges. This theory, introduced by Harry Hess, was proven as patterns of magnetic field polarity preserved in seafloor basalt and by age dating of the rocks . Hess argued that the Mid-Atlantic Ridge was a boundary where two lithospheric plates were rifting (being pulled apart). As that happened, rising magma from the upper part of the mantle filled in the cracks that formed in the earth's crust . After the magma solidified into basalt and igneous rock, additional rifting pulled those rocks apart too. very slowly over time, widening the Atlantic Ocean basin and pushing apart the continents to either side.

7. MAJOR PHYSIOGRAPHIC DIVISIONS (1) The Himalayan Mountains (2) The Northern Plains (3) The Peninsular Plateau (4) The Indian Desert (5) The Coastal Plains (6) The Islands

8. The Himalayas are the youngest mountains in the world and are; structurally; the folded mountains. These Himalayas run along the northern border of India . Himalayas form an arc which is about 2,400 km long. The width varies from 400 km in Kashmir to 150 km in Arunachal Pradesh. The altitudinal variations are greater in the eastern part than in the western part. There are three parallel ranges in its longitudinal extent.

9. (3) The Shiwaliks :- This is the outermost range of the Himalayas. The altitude varies between 900 and 1100 km in this range and the width varies between 10 to 50 km. These ranges are composed of unconsolidated sediments. The longitudinal valleys lying between the Himachal and Shiwaliks are called ‘Dun’. (1) The Great or Inner Himalayas:- This is the northernmost range and is also known as ‘ Himadri ’. This is the most continuous range. It contains the loftiest peaks. The average height of peaks in this range is 6,000 meters . All the prominent Himalayan peaks are in this range. The Great Himalayas are asymmetrical in nature and the core of this part is composed of granite. Because of the lofty heights, the peaks of this range are perennially snow-bound. (2) The Lesser Himalaya or Himachal: This lies towards the south of the Great Himalayas. The altitude of peaks in this range varies from 3,700 m to 4,500 m. Average width of this range is 50 km. This range is mainly composed of highly compressed and altered rocks.

10. Greater Himalayas It extends southeastward across northern  Pakistan , northern  India , and  Nepal . it adjoins to the north the southern   Tibet   Autonomous  Region of  China . The range’s total length is some 1,400 miles (2,300 km), and it has an average elevation of more than 20,000 feet (6,100 metres ). The Great Himalayas contain many of the world’s tallest peaks, including (from west to east)  Nanga Parbat ,  Annapurna ,  Mount Everest , and  Kanchenjunga .

11. Passes in the Great Himalayas — Karakoram pass, Shipkila pass, Nathula , Bomdila pass .

12. Which glaciers and passes lie in great Himalayas? Ans. Glaciers in the Great Himalayas —  (a) Siachen Glacier – Jammu and Kashmir ( b) Godwin Glacier – Jammu and Kashmir ( c) Gangotri Glacier – Uttarakhand ( d) Yamunotri Glacier – Uttarakhand Yamnotri

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

14. The Shivaliks The outer-most range of the Himalayas is called the Shiwaliks . They extend over a width of 10-50 Km and have an altitude varying between 900 and 1100 meters. These ranges are composed of unconsolidated sediments brought down by rivers from the main Himalayan ranges located farther north . The longitudinal valley lying between lesser Himalaya and the Shiwaliks are known as Duns. Dehra Dun (Jharkhand), Kotli Dun (HP) and Patli Dun (Punjab) are some of the well-known Duns.

15. West to East division of Himalayas Himalayas have been divided on the basis of regions from west to east. Himalayas lying between Indus and Satluj has been traditionally known as Punjab Himalaya but it is also known regionally as Kashmir and Himachal Himalaya from west to east respectively. Himalayas lying between Satluj and Kali rivers is known as Kumaon Himalayas. The Kali and Teesta rivers demarcate the Nepal Himalayas. Part lying between Teesta and Dihang rivers is known as Assam Himalayas . Himalayas bend sharply to the south and spread along the eastern boundary of India. They are known as the Purvachal or the Eastern hills and mountains. The Purvachal comprises the Patkai hills , the Naga hills, the Manipur hills and the Mizo hills.

16. The Northern Plain The northern plain of India is formed by three river systems, viz. the Indus , the Ganga and the Brahmaputra; along with their tributaries . This plain is composed of alluvial soil which has been deposited over millions of years. The total area of the northern plain is about 7 lakh square kilometer. It is about 2400 km long and about 240 to 320 km broad

17. The rivers coming from northern form riverine islands. Majuli , in the Brahmaputra river, is the largest inhabited riverine island in the world.

18. The northern plain is divided into three sections , The Punjab Plain The Ganga Plain The Brahmaputra Plain. Punjab Plains: The Punjab plains form the western part of the northern plain. This is formed by the Indus and its tributaries ; like Jhelum, Chenab, Ravi, Beas and Sutlej. A major portion of this plains is in Pakistan. Doabs are founds in this region. Ganga Plains: This plain extends between Ghaggar and Tista rivers . The northern states, Haryana, Delhi, UP, Bihar, part of Jharkhand and West Bengal lie in the Ganga plains. Brahmaputra Plains: This plain forms the eastern part of the northern plain and lies in Assam.

19. Relief features of the northern plains Bhabar : After descending from the mountains, the rivers deposit pebbles in a narrow belt. The width of this belt is about 8 to 16 km and it lies parallel to the Shiwaliks . All the streams disappear in this region. Terai : The terai region lies towards south of the bhabar belt. In this region, the streams reappear and make a wet, swampy and marshy region. Bhangar : Bhangar is the largest part of the northern plain and is composed of the oldest alluvial soil. They lie above the flood plains. The soil of this region is locally known as kankar and is composed of calcareous deposits. Khadar : The floodplains formed by younger alluvium are called khadar . The soil in this region is renewed every year and is thus highly fertile.

20. The Peninsular Plateau The Peninsular plateau is a tableland composed of the old crystalline, igneous and metamorphic rocks. It was formed due to the breaking and drifting of the Gondwana land and thus, making it a part of the oldest landmass. This plateau consists of two broad divisions, namely, the Central Highlands and the Deccan Plateau.

21. Central Highland The part of the Peninsular plateau lying to the north of the Narmada river, covering a major area of the Malwa plateau, is known as the Central Highlands . The Vindhyan range is bounded by the Satpura range on the south and the Aravalis on the northwest. T he Chambal, the Sind, the Betwa and the Ken Drain this region and flows from southwest to northeast, thus indicating the slope . The eastward extensions of this plateau are locally known as the Bundelkhand and Baghelkhand . The Chotanagpur plateau marks the further eastward extension, drained by the Damodar river. Narmada

22. 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 eastern extensions . Locate these hills on map. The Deccan Plateau is higher in the west and slopes gently eastwards .

23. An extension of the Plateau is also visible in the northeast, locally known as the Meghalaya, Karbi-Anglong Plateau and North Cachar Hills. It is separated by a fault from the Chotanagpur Plateau . Three prominent hill ranges from the west to the east are the Garo, the Khasi and the Jaintia Hills. Garo, Khasi, Jaintia

24. Th e Western Ghats and the Eastern Ghats These mark the western and the eastern edges of the Deccan Plateau respectively. Western Ghats lie parallel to the western coast. They are continuous and can be crossed through passes only. Locate the Thal , Bhor and Pal Ghats in the Physical map of India. The Western Ghats are higher than the Eastern Ghats. Their average elevation is 900– 1600 metres as against 600 metres of the Eastern Ghats.

25. The Western Ghats cause orographic rain by facing the rain bearing moist winds to rise along the western slopes of the Ghats. The height of the Western Ghats progressively increases from north to south . The highest peaks include the Anai Mudi (2,695 metres ) and the Doda Betta (2,637 metres ).

26. The Eastern Ghats stretch from the Mahanadi Valley to the Nigiris in the south. The Eastern Ghats are discontinuous and irregular and dissected by rivers draining into the Bay of Bengal . Mahendragiri (1,501 metres ) is the highest peak in the Eastern Ghats. Shevroy 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 .

27. The Indian Desert The Indian desert lies towards the western margins of the Aravali Hills. This region receives very low rainfall below 150 mm per year. It has arid climate with low vegetation cover. Streams appear during the rainy season . Soon after they disappear into the sand as they do not have enough water to reach the sea. Luni is the only large river in this region . Barchans (crescent-shaped dunes) cover larger areas but longitudinal dunes become more prominent near the Indo-Pakistan boundary

28. The Coastal Plains The Peninsular plateau is narrow coastal strips, running along the Arabian Sea on the west and the Bay of Bengal on the east . The western coast , is a narrow plain. It consists of three sections . The northern part of the coast is called the Konkan (Mumbai – Goa), the central stretch is called the Kannad Plain, while the southern stretch is referred to as the Malabar coast . The plains along the Bay of Bengal are wide and level. In the northern part, it is referred to as the Northern Circar , while the southern part is known as the Coromandel Coast . Large rivers , such as the Mahanadi, the Godavari, the Krishna and the Kaveri have formed extensive delta on this coast. Chilika Lake is an important feature along the eastern coast. Chilika lake

29. THE ISLANDS Lakshadweep Islands group lying close to the Malabar coast of Kerala . This group of islands is composed of small coral isalnds (36). Earlier they were known as Laccadive, Minicoy and Amindive . In 1973, these were named as Lakshadweep . It covers small area of 32 sq km. Kavaratti island is the administrative headquarters of Lakshadweep . This island group has great diversity of flora and fauna. The Pitti island, which is uninhabited , has a bird sanctuary.

30. Andaman and Nicobar Andaman and Nicobar is a chain (572) of Islands located in Bay of Bengal. They are bigger in size and are more numerous and scattered. The Andaman in the north and the Nicobar in the south. It is believed that these islands are an elevated portion of submarine mountains . There is great diversity of flora and fauna in this group of islands too. These islands lie close to equator and experience equatorial climate and has thick forest cover.