Revision: Contemporary India - 1 >> Physical Features of India Social Science English Medium Class 9 CBSE

Range: a vast landmass made of peaks, ridges, and mountains.
Hills: A hill is a landform that extends above the surrounding terrain and a more rounded/mound shape than a distinct peak.

Key Points: Physical Division of India > The Northern Mountain Walls

The Himalayas are young fold mountains forming India’s Northern Mountain Wall, with three parallel ranges—Himadri, Himachal and Shiwalik.
Himadri (Great Himalayas) is the highest and northernmost range, permanently snow-covered, with peaks like Mt. Everest, K2 and Kanchenjunga and major glaciers.
Himachal (Middle Himalayas) lies south of Himadri, has rich vegetation, important ranges (Pir Panjal, Dhaula Dhar) and most hill stations.
Shiwalik (Outer Himalayas) is the lowest and discontinuous range, with steep southern slopes, gentle northern slopes and average height of about 1000 m.
Special Himalayan features include Doons (valleys), Bhabhar (porous plains), Terai (marshy belt) and fertile Khadar and Bhangar alluvial soils.

Key Points: Physical Division of India> The Himalayas

The Himalayas are young fold mountains and one of the major mountain systems in Asia.
They extend from the Pamir Knot in Tajikistan to eastern India (Jammu & Kashmir to Arunachal Pradesh).
The Himalayas consist of parallel mountain ranges: the Siwaliks (youngest), the Lesser Himalayas, the Greater Himalayas (Himadri), and the Trans-Himalayas (oldest).
The ranges are arranged south to north by age — youngest in the south, oldest in the north.
The Himalayas are divided into Western (Kashmir), Central (Kumaun), and Eastern (Assam) Himalayas.

Key Points: Physical Divisions of India> North Indian Plains

The North Indian Plains lie between the Himalayas and the Peninsular Plateau, from Rajasthan to Assam.
They were formed by alluvial deposits from the Indus, Ganga, and Brahmaputra rivers.
These plains are flat, low-lying, and suitable for farming and settlements.
They cover one-fifth of India’s area but support nearly half of the population.
The plains are divided into Rajasthan, Punjab–Haryana, the Ganga Plains, and the Brahmaputra Plains.
The Punjab–Haryana and Ganga Plains are fertile, irrigated, and densely populated.
The Brahmaputra Plains are marshy and include Majuli Island; the Sunderbans Delta is the world’s largest.

Key Points: Physical Divisions of India> The Peninsula

The Indian Peninsula lies south of the North Indian Plains and tapers toward the Indian Ocean.
It is the oldest and largest physiographic division of India, mostly made of stable tableland.
It is bounded by the Aravalli Range in the northwest and the Western and Eastern Ghats on the sides.
The region includes many hill ranges and plateaus, such as the Vindhyas, Satpuda, and Aravalis.
The Deccan Plateau is triangular and lies between the Western and Eastern Ghats, covering Maharashtra, Telangana, and Karnataka.
The plateau is divided into Central Plateaus, Eastern Plateaus, Deccan Plateau, Kathiawar–Kutch region, and North-Eastern Plateau.
This region is rich in minerals, has old rivers, and supports forests, farming, and mining.

Key Points: Physical Divisions of India> The Coastal Plains

India has a coastline of approximately 7,500 km, extending along the eastern (Bay of Bengal) and western (Arabian Sea) sides of the Peninsula, meeting at Cape Comorin.
The Western Coastal Plains are narrow, rocky, and indented, with short rivers forming estuaries; major ports include Mumbai and Kochi.
The Eastern Coastal Plains are broad and flat, formed by deposition from major rivers like the Mahanadi, Godavari, Krishna, and Kaveri, leading to fertile deltas.
Subdivisions: East coast – Northern Circars and Coromandel Coast; West coast – Gujarat, Konkan, Kanara, Malabar.
The coastal plains are important for ports, minerals (like salt and monazite), and fisheries.

Key Points: Physical Divisions of India> The Island Group

India has two major island groups: the Lakshadweep Islands in the Arabian Sea and the Andaman & Nicobar Islands in the Bay of Bengal.
The Lakshadweep Islands are mostly coral atoll islands, small, flat, and low in height, and lie off the Kerala coast.
The Andaman & Nicobar Islands consist of many islands (about 265–300), mostly forested and hilly, and are separated by the Ten Degree Channel.
Barren Island in the Andaman group has India’s only active volcano, and Indira Point in Great Nicobar is India’s southernmost point.
These island groups are important for strategic location, biodiversity, and are surrounded by coral reefs and rich marine life.