Class 9 Geography Chapter 2 Notes

Physical Features of India Class 9 Geography Chapter 2 Notes are available here. These notes are prepared by the subject experts of CBSE Wale.

Physical Features of India Class 9 Geography Chapter 2 Notes

• India has varied landforms and is a vast country.
• The type of terrain varies based on location:
• Plains: vast stretches of plain land.
• Hilly regions: rugged terrain with mountains and valleys.
• India has all major physical features of the earth: mountains, plains, deserts, plateaus, and islands.
• The land of India displays significant physical variation.
• The Peninsular Plateau is one of the ancient and stable landmasses.
• The Himalayas and the Northern Plains are recent landforms geologically.
• The Himalayas are an unstable zone with youthful topography, high peaks, deep valleys, and fast-flowing rivers.
• The Northern Plains are formed of alluvial deposits.
• The Peninsular Plateau is composed of igneous and metamorphic rocks, featuring gently rising hills and wide valleys.

Major Physiographic Divisions

India’s physical features are divided into six 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

The Himalayan Mountains

• The Himalayas are geologically young and structurally fold mountains.
• They stretch over the northern borders of India, running west-east from the Indus to the Brahmaputra.
• The Himalayas are the loftiest and one of the most rugged mountain barriers in the world.
• They form an arc covering a distance of about 2,400 km.
• The width of the Himalayas varies from 400 km in Kashmir to 150 km in Arunachal Pradesh.
• Altitudinal variations are greater in the eastern half than in the western half.
• The Himalayas consist of three parallel ranges in their longitudinal extent.
• Several valleys lie between these ranges.
• The northern-most range is known as the Great or Inner Himalayas, or the Himadri.
• The Himadri is the most continuous range, consisting of the loftiest peaks with an average height of 6,000 meters.
• It contains all prominent Himalayan peaks.

List of some highest peaks of the Himalayas:

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

• The folds of the Great Himalayas are asymmetrical.
• The core of the Great Himalayas is composed of granite.
• This part of the Himalayas is perennially snow-bound and has many glaciers.
• The Himachal or Lesser Himalaya lies south of the Himadri and forms the most rugged mountain system.
• The Himachal ranges are composed mainly of highly compressed and altered rocks.
• The altitude of the Himachal ranges varies between 3,700 and 4,500 meters, with an average width of 50 km.
• The Pir Panjal range is the longest and most important range in the Himachal Himalaya.
• Other prominent ranges include the Dhaula Dhar and Mahabharat ranges.
• The Himachal range contains the famous valleys of Kashmir, Kangra, and Kullu in Himachal Pradesh.
• This region is well-known for its hill stations.
• The outer-most range of the Himalayas is called the Shiwaliks.
• The Shiwaliks extend over a width of 10-50 km.
• The altitude of the Shiwaliks varies between 900 and 1100 meters.
• These ranges are composed of unconsolidated sediments brought down by rivers from the main Himalayan ranges to the north.
• The valleys of the Shiwaliks are covered with thick gravel and alluvium.
• The longitudinal valleys lying between the Lesser Himalaya and the Shiwaliks are known as Duns.
• Notable Duns include Dehra Dun, Kotli Dun, and Patli Dun.
• The Himalayas are divided into regions from west to east based on river valleys.
• The part of the Himalayas between the Indus and Satluj rivers is known as Punjab Himalaya, regionally referred to as Kashmir and Himachal Himalaya from west to east respectively.
• The section between the Satluj and Kali rivers is called Kumaon Himalayas.
• The area between the Kali and Teesta rivers is known as Nepal Himalayas.
• The region between the Teesta and Dihang rivers is called Assam Himalayas.
• These broad categories also have regional names.
• 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.
• This region is known as the Purvachal or the Eastern hills and mountains.
• The hills in this region run through the north-eastern states of India.
• These hills are mostly composed of strong sandstones, which are sedimentary rocks.
• The hills are covered with dense forests.
• They mostly run as parallel ranges and valleys.
• The Purvachal includes 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 three major river systems: the Indus, the Ganga, and the Brahmaputra, along with their tributaries.
• This plain is composed of alluvial soil.
• The deposition of alluvium in a vast basin at the foothills of the Himalayas over millions of years formed this fertile plain.
• The Northern Plain covers an area of 7 lakh sq. km.
• It is about 2400 km long and 240 to 320 km broad.
• The Northern Plain is a densely populated physiographic division.
• With rich soil, adequate water supply, and a favorable climate, it is an agriculturally productive part of India.
• Rivers coming from the northern mountains are involved in depositional work.
• In the lower course of these rivers, the velocity decreases due to the gentle slope, leading to the formation of riverine islands.
• In their lower course, rivers split into numerous channels due to silt deposition.
• These channels are known as distributaries.
• Majuli, in the Brahmaputra river, is the largest inhabited riverine island in the world.
• The Northern Plain is broadly divided into three sections.
• The western part of the Northern Plain is known as the Punjab Plains.
• The Punjab Plains are formed by the Indus and its tributaries.
• The larger part of this plain lies in Pakistan.
• The Indus and its tributaries — the Jhelum, Chenab, Ravi, Beas, and Satluj — originate in the Himalayas.
• This section of the plain is dominated by the doabs.
• The term ‘doab’ means ‘two waters’ (from ‘do’ meaning two and ‘ab’ meaning water).
• The term ‘Punjab’ means ‘five waters’ (from ‘Punj’ meaning five and ‘ab’ meaning water).
• The Ganga plain extends between the Ghaggar and Teesta rivers.
• It is spread over North India in Haryana, Delhi, Uttar Pradesh, Bihar, partly Jharkhand, and West Bengal.
• To the east, particularly in Assam, lies the Brahmaputra plain.
• The northern plains are not entirely flat; they have diverse relief features.
• The Northern plains can be divided into four regions based on relief variations:
• Bhabar: A narrow belt (8 to 16 km wide) where rivers deposit pebbles and all streams disappear.
• Terai: South of the bhabar belt, where streams and rivers re-emerge, creating a wet, swampy, and marshy region.
• The Terai region was once thickly forested and full of wildlife but has been cleared for agriculture and settlement of migrants from Pakistan after partition.
• Dudhwa National Park is located in this region.
• The largest part of the northern plain is formed of older alluvium.
• This area lies above the floodplains of the rivers and has a terrace-like feature.
• This part is known as bhangar.
• The soil in the bhangar region contains calcareous deposits, locally known as kankar.
• Newer, younger deposits of the floodplains are called khadar.
• Khadar is renewed almost every year, making it fertile and ideal for intensive agriculture.

The Peninsular Plateau

• The Peninsular plateau is a tableland composed of old crystalline, igneous, and metamorphic rocks.
• It was formed due to the breaking and drifting of Gondwana land, making it part of the oldest landmass.
• The plateau features broad and shallow valleys and rounded hills.

The Peninsular plateau consists of two broad divisions:

1. Central Highlands: Located north of the Narmada river, covering a major area of the Malwa plateau.
2. Deccan Plateau: The other division not detailed in this paragraph.

The Central Highlands are bounded by:

1. The Vindhyan range to the north.
2. The Satpura range to the south.
3. The Aravalis to the northwest.

• The western extension of the Central Highlands merges with the sandy and rocky desert of Rajasthan.
• Rivers draining the Central Highlands, such as the Chambal, Sind, Betwa, and Ken, flow from southwest to northeast, indicating the region’s slope.
• The Central Highlands are wider in the west and narrower in the east.
• The eastward extensions of this plateau are known as the Bundelkhand and Baghelkhand.
• The Chotanagpur plateau extends further east and is drained by the Damodar river.
• The Deccan Plateau is a triangular landmass located south of the river Narmada.
• The Satpura range flanks the broad base of the Deccan Plateau in the north.
• The eastern extensions of the Deccan Plateau include the Mahadev, Kaimur hills, and Maikal range.
• The Deccan Plateau is higher in the west and slopes gently eastwards.
• An extension of the Plateau in the northeast is known as the Meghalaya, Karbi-Anglong Plateau, and North Cachar Hills.
• The northeast extension is separated from the Chotanagpur Plateau by a fault.
• Three prominent hill ranges from west to east are the Garo, Khasi, and Jaintia Hills.
• The Western Ghats and the Eastern Ghats mark the western and eastern edges of the Deccan Plateau, respectively.
• The Western Ghats lie parallel to the western coast and are continuous, crossed only through passes such as the Thal, Bhor, and Pal Ghats.
• The Western Ghats are higher than the Eastern Ghats, with an average elevation of 900–1600 meters compared to 600 meters for the Eastern Ghats.
• The Eastern Ghats stretch from the Mahanadi Valley to the Nilgiris in the south and are discontinuous, irregular, and dissected by rivers draining into the Bay of Bengal.
• The Western Ghats cause orographic rain by forcing moist winds to rise along their western slopes.
• The Western Ghats are known by various local names and their height increases progressively from north to south.
• The highest peaks in the Western Ghats are Anai Mudi (2,695 meters) and Doda Betta (2,637 meters).
• Mahendragiri (1,501 meters) is the highest peak in the Eastern Ghats.
• The Shevroy Hills and the Javadi Hills are located southeast of the Eastern Ghats.
• The famous hill stations of Udagamandalam (Ooty) and Kodaikanal are located in this region.
• The Peninsular plateau features a black soil area known as the Deccan Trap.
• The Deccan Trap is of volcanic origin, with igneous rocks responsible for its formation.
• Over time, these rocks have denuded and contributed to the formation of black soil.
• The Aravali Hills lie on the western and northwestern margins of the Peninsular plateau.
• The Aravali Hills are highly eroded and appear as broken hills.
• They extend from Gujarat to Delhi in a southwest-northeast direction.

The Indian Desert

• The Indian desert is located towards the western margins of the Aravali Hills.
• It is an undulating sandy plain covered with sand dunes.
• The region receives very low rainfall, below 150 mm per year.
• It has an arid climate with low vegetation cover.
• Streams appear during the rainy season but soon disappear into the sand due to insufficient water to reach the sea.
• The Luni is the only large river in this region.
• Barchans (crescent-shaped dunes) cover larger areas, while longitudinal dunes are more prominent near the Indo-Pakistan boundary.
• Jaisalmer is a notable location where you can see a group of barchans.

The Coastal Plains

• The Peninsular plateau is flanked by narrow coastal strips.
• These strips run along the Arabian Sea on the west and the Bay of Bengal on the east.
• The western coast is sandwiched between the Western Ghats and the Arabian Sea.

It is a narrow plain divided into three sections:

1. Konkan: Northern part of the coast (Mumbai – Goa).
2. Kannad Plain: Central stretch.
3. Malabar Coast: Southern stretch.

• India has two groups of islands.
• One group is the Lakshadweep Islands, located close to the Malabar coast of Kerala.
• The Lakshadweep Islands are composed of small coral islands.
• Previously known as Laccadive, Minicoy, and Amindive, they were renamed Lakshadweep in 1973.
• The Lakshadweep group covers a small area of 32 sq km.
• Kavaratti Island is the administrative headquarters of Lakshadweep.
• The island group has a great diversity of flora and fauna.
• Pitti Island, which is uninhabited, features a bird sanctuary.
• The elongated chain of islands located in the Bay of Bengal extends from north to south.
• These islands are known as the Andaman and Nicobar Islands.
• The islands are larger, more numerous, and scattered.

The entire group is divided into two broad categories:

1. The Andaman Islands in the north.
2. The Nicobar Islands in the south.

• The islands are believed to be an elevated portion of submarine mountains.
• The island groups hold significant strategic importance for the country.
• They have a great diversity of flora and fauna.
• The islands lie close to the equator, experiencing an equatorial climate and thick forest cover.
• India’s only active volcano is located on Barren Island in the Andaman and Nicobar group of islands.
• Each physiographic unit in India has unique features.
• Regions complement each other, enriching the country’s natural resources.
• Mountains are major sources of water and forest wealth.
• The northern plains serve as the granaries of the country and provided the base for early civilizations.
• The plateau is a storehouse of minerals crucial for industrialization.
• The coastal regions and island groups are important for fishing and port activities.
• The diverse physical features of the land offer significant future development possibilities.