Physical Features of India Class 9 Notes Social Science Geography Chapter 2
Since the previous 3 years’ examinations, the factual questions (Very Short Answer Type) have been asking relevant to various physical divisions of India consisting of the following topics :
- Location
- The Himalayan Mountains
- The Northern Plains
- The Peninsular Plateau
- The Indian Desert
- The Coastal Plains
- The Islands.
Location
India has all major physical features of the Earth, i.e., mountains, plains, deserts, plateaus, and islands.
In India, the soil colour varies from place to place as it is formed from different types of rocks.
India has varied physical features whose formation can be explained on the basis of the ‘Theory of Plate Tectonics’.
According to the theory of Plate Tectonics, the seven major and minor plates that form the Earth’s crust keep moving, causing stress and thus leading to folding, faulting and volcanic activity.
The physical features of India can be grouped under the following physiographic divisions:
- The Himalayan Mountains or the Northern Mountains
- The Northern Plains or the Indo-Gangetic Plains
- The Peninsular Plateau
- The Great Indian Desert
- The Coastal Plains
- The Islands
The Himalayan Mountains
The Himalayas are young-fold mountains which are the loftiest and one of the most rugged mountain barriers of the world.
The Himalayas are 2400 km long, 400 km to 150 km wide from Kashmir to Arunachal Pradesh respectively.
The Himalayas have three parallel ranges in the longitudinal extent namely :
- Great or Inner Himalayas also called Himadri.
- Middle Himalayas or Himachal.
- Outer Himalayas or Shiwaliks.
The Himalayas can be divided into four sections :
- Punjab Himalayas – between Indus and Satluj.
- Kumaon Himalayas – between Satluj and Kali.
- Nepal Himalayas – between Kali and the Tista.
- Assam Himalayas (Eastern Himalayas) – Between Tista and the Dibang (Tsangpo).
The Northern Plains
The Northern Plains spread over an area of 7 lakh sq. km, 240 km long and 240 km to 320 km broad.
The rivers that flow to the plains from the mountains are involved in depositional work.
The difference in relief causes the Northern Plains to have four regions.
- Bhabar – Adjacent to the foothills of Shiwaliks, a narrow 8 to 16 km wide belt of pebbles and boulders.
- Bangar – Older alluvial plain which rises above the level of the flood plains.
- Khadar – Newer and younger alluvial of the flood plains deposited by the rivers flowing down the plain.
- Tarai – Lies adjacent to Bhabar region, composed of newer alluvium and is thickly forested.
The Peninsular Plateau
The Peninsular Plateau is the tableland formed due to the breaking and drifting of the Gondwanaland.
The plateau consists of two broad divisions, namely, the Central Highlands and the Deccan Plateau.
The eastward extensions of Peninsular Plateau are locally known as Bundelkhand and Baghelkhand. The Chhota Nagpur Plateau marks the further eastward extension drained by the Damodar river.
The Deccan Plateau, a triangular mass, lies to the south of the river Narmada.
The western and eastern edges of the Deccan Plateau are marked by the Western Ghats and the Eastern Ghats respectively.
The Western Ghats are higher than the Eastern Ghats.
The Malwa Plateau is spread across Rajasthan, Madhya Pradesh and Gujarat and slopes towards the
north.
A distinct feature of the peninsular plateau is the black soil area known as Deccan Trap.
The Indian Desert
The undulating sandy plain covered with sand dunes towards the western margins of the Aravalli Hills is the Indian Desert.
Crescent-shaped dunes called barchans cover large parts of the Indian Desert.
Luni is the only large river that flouts in this region.
The Coastal Plains
The narrow’ coastal strips flank the Peninsular Plateau.
On the west, the coastal strips are divided into Konkan (Mumbai-Goa), Kannada Plain and the Malabar Coast from northern to the southern part.
On the east the coastal strip is divided into Northern Circar and the Coromandel Coast from northern to southern part.
The Islands
The Lakshadweep Islands group in the Arabian Sea is close to Kerala.
The Andaman and Nicobar Islands are the two island groups. Andaman Island consists of 204 small islands. India’s only active volcano, Barren Island is situated here.
Major Physiographic Divisions
The physical features of India are grouped under the following physiographic divisions:
- The Himalayan Mountains
- The Northern Plains
- The Peninsular Plateau
- The Indian Desert
- The Coastal Plains
- The Islands
Let’s discuss each of them in detail:
The Himalayan Mountains
Himalayan mountains are stretched over the northern borders of India. These mountain ranges run in a west-east direction from the Indus to the Brahmaputra. The Himalaya consists of 3 parallel ranges in its longitudinal extent.
- 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 with an average height of 6,000 metres.
- The folds of the Great Himalayas are asymmetrical in nature. The core of this part of Himalayas is composed of granite.
- The range lying to the south of the Himadri forms the most rugged mountain system and is known as Himachal or lesser Himalaya.
- Pir Panjal range forms the longest and the most important range.
- The outermost range of the Himalayas is called the Shiwaliks. These ranges are composed of unconsolidated sediments.
- The longitudinal valley lying between lesser Himalaya and the Shiwaliks are known as Duns. DehraDun, Kotli Dun and Patli Dun are some of the well-known Duns.
The Himalayas have also been divided on the basis of regions from west to east.
- The part of 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.
- The part of the Himalayas lying between Satluj and Kali rivers is known as Kumaon Himalayas.
- The Kali and Teesta rivers divide the Nepal Himalayas and the part lying between Teesta and Dihang rivers is known as Assam Himalayas.
- The Brahmaputra marks the eastern-most boundary of the Himalayas.
- Beyond the Dihang gorge, the Himalayas bend sharply to the south and spread along the eastern boundary of India, which is 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.
The Northern Plain
The northern plain has been formed by the interplay of the 3 major river systems – the Indus, the Ganga and the Brahmaputra along with their tributaries. It spreads over an area of 7 lakh sq. km.
The Northern Plain is broadly divided into 3 sections as mentioned below:
- The Western part of the Northern Plain is referred to as the Punjab Plains. This plain is formed by the Indus and its tributaries – the Jhelum, the Chenab, the Ravi, the Beas and the Satluj.
- The Ganga plain extends between Ghaggar and Teesta rivers. It is spread over the states of North India, Haryana, Delhi, U.P., Bihar, partly Jharkhand and West Bengal.
- Brahmaputra plain lies in the state of Assam.
According to the variations in elevation points, the Northern plains can be divided into 4 regions.
- The rivers, after descending from the mountains, deposit pebbles in a narrow belt of about 8 to 16 km in width lying parallel to the slopes of the Shiwaliks, which is known as bhabar. All the streams disappear in this bhabar belt.
- The streams and rivers re-emerge and create a wet, swampy and marshy region known as terai.
- The largest part of the northern plain is formed of older alluvium. It lies above the floodplains of the rivers and presents a terracelike feature which is known as bhangar.
- The soil in the bhangar region contains calcareous deposits and is known as kankar. The newer, younger deposits of the floodplains are called khadar.
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. One of the distinct features of the Peninsular plateau is the black soil area known as Deccan Trap.
This plateau consists of 2 divisions:
- The Central Highlands: 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 eastward extensions of this plateau are locally known as the Bundelkhand and Baghelkhand.
- The Deccan Plateau: It is a triangular landmass that lies to the south of the river Narmada. An extension of the Plateau is also visible in the northeast, which is known as the Meghalaya, Karbi-Anglong Plateau and North Cachar Hills.
The Western Ghats and the Eastern Ghats mark the western and the eastern edges of the Deccan Plateau respectively.
Western Ghats | Eastern Ghats |
Western Ghats lie parallel to the western coast. | The Eastern Ghats stretch from the Mahanadi Valley to the Nigiris in the South. |
They are continuous and can be crossed through passes only. | They are discontinuous and irregular. They can be dissected by rivers draining into the Bay of Bengal. |
They are higher than the Eastern Ghats. Their average elevation is 900–1600 metres. | Their average elevation is 600 metres. |
Anamudi is the highest peak in the Western Ghats. | Mahendragiri (1,501 metres) is the highest peak in the Eastern Ghats. |
The Indian Desert
The Indian desert lies towards the western margins of the Aravali Hills.
- It is a sandy plain covered with sand dunes.
- This region receives very low rainfall below 150 mm per year.
- It has a dry climate with low vegetation cover.
The Coastal Plains
A coastal plain is a flat, low-lying piece of land next to the ocean. To the east and west of the peninsular plateau, 2 narrow strips of plain lands are found, which are respectively called Eastern Coastal Plain and Western Coastal Plain.
Eastern Coastal Plain
The Eastern Coastal Plains is a wide stretch of the landmass lying between the Eastern Ghats and the Bay of Bengal. 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. Lake Chilika is an important feature along the eastern coast.
Western Coastal Plain
The western coast is sandwiched between the Western Ghats and the Arabian Sea. It is a narrow plain and consists of 3 sections as mentioned below:
- The northern part of the coast is called the Konkan (Mumbai – Goa)
- The central stretch is called the Kannad Plain
- The southern stretch is referred to as the Malabar coast
The Islands
An island is a piece of sub-continental land that is surrounded by water. Lakshadweep Islands group is composed of small coral isalnds which were earlier known as Laccadive, Minicoy and Amindive.
The entire group of islands is divided into 2 broad categories:
- The Andaman in the north
- The Nicobar in the south
These islands lie close to the equator and experience equatorial climate and have thick forest cover.
The diverse physical features of India have immense future possibilities of development because of the following reasons.
- The mountains are the major sources of water and forest wealth.
- The northern plains are the granaries of the country. They provide the base for early civilisations.
- The plateau is a storehouse of minerals, which has played a crucial role in the industrialisation of India.
- The coastal region and island groups provide sites for fishing and port activities.