TNPSC Geography Free Notes – Physiographic Divisions of India

இந்தக் கட்டுரையில், TNPSC குரூப் 1, குரூப் 2, குரூப் 2A, குரூப் 4 மாநிலப் போட்டித் தேர்வுகளான TNUSRB, TRB, TET, TNEB போன்றவற்றுக்கான  முறைகள் இலவசக் குறிப்புகளைப் பெறுவீர்கள்.தேர்வுக்கு தயாராவோர் இங்குள்ள பாடக்குறிப்புகளை படித்து பயன்பெற வாழ்த்துகிறோம்.

Indian Standard Meridian passes through UP, MP, Chhatisgarh, Orissa and Andhra Pradesh
Physiographic Divisions of India

Divided into the following six physiographic divisions:
1. The Himalayan Mountains
2. The Great Northern Plains
3. The Peninsular plateau
4. The Indian Desert
5. The Coastal Plains
6. The Islands
Form of Himalayan Mountains
 The Himalayan Mountains (Northern Mountains) consist of the youngest and the
Loftiest mountain chains in the world.
 Because they have been formed only few millions years ago and also they were formed
because of the folding of the earth crust due to tectonic activity.
 The Pamir Knot popularly known as the roof of the world.
 It is the connecting link between the Himalayas and the high ranges of Central Asia.
 From the Pamir, Himalayas extend eastward in the form of an arc shape.
 The term “Himalaya” is derived from Sanskrit. It means “Th e Abode of Snow”.
The Northern Mountains that function as a great wall is grouped into three divisions.

1. The Trans-Himalayas
2. Himalayas
3. Eastern or Purvanchal hills.
Aravalli range is the oldest fold mountain range in India.
The Trans-Himalayas
 It lies in Jammu and Kashmir and Tibetian plateau.
 As its areal extent is more in Tibet, it is also known as Tibetan Himalayas.
 They contain the Tethys sediments. The rocks of this region contain fossils bearing
marine sediments which are under laid by ‘Tertiary granite’
 The prominent ranges of Trans Himalayas are Zaskar, Ladakh, Kailash, and Karakoram.
Central Himalayas
 It constitutes the core part of northern mountains. It is an young fold mountain.
 It was formed by the movement of Angara land mass in the north and Gondwana land
mass in the south.
 The Tethys Sea found between these two land masses was uplifted by the compression
and the resultant landform was the Himalayas.
The main divisions of the Himalayas are the
1. Greater Himalayas
2. the Lesser Himalayas and
3. the Siwaliks
 Mt. Everest – Nepal – 8848m
 Mt.K2 or Godwin Austin – India – 8611m
 Kanchenjunga – India – 8586m
 Makalu – Nepal – 8481m
 Dhaulagiri – Nepal – 8172m
 Nanda Parbat – India – 8126m
 Annapurna – Nepal – 8078m
 Nanda Devi – India -7817m
 Kamet – India – 7756m
 Namcha Barwa – India – 7756m
 Gurla Mandhata – Nepal – 7728m

The main divisions of the central Himalayas are the
1. Greater Himalayas

2. The Lesser Himalayas
3. The Siwaliks
1. The Greater Himalayas or the Himadri
 The Greater Himalayas rise abruptly like a wall north of the Lesser Himalayas.
 The Greater Himalayas are about 25 km wide. Its average height is about 6,000 m. The
Greater Himalayas receive lesser rainfall as compared to the Lesser Himalayas and the
Siwaliks.
 Almost all the lofty peaks of Himalayas are located in this range.
 The Everest (8,848) m) and Kanchenjunga (8,586 m). Mt.Everest is located in Nepal and
Kanchenjunga is located between Nepal and Sikkim.
 Out of 14 highest peaks in this world, Himalayas holds 9.
 It has many glaciers. Gangothri, Yamunothri and Siachen are some of them.
2. The Lesser Himalayas or the Himachal
 Its width varies upto 80 km.
 The major rocks of this range are slate, limestone and quartzite.
 Pir Panjal, Dhauladhar and Mahabharat are the mountain ranges found in this part.
 Shimla, Mussourie, Nainital, Almora, Ranikhet and Darjeeling are the familiar ones.
The major Passes:
 Karakoram pass (Jammu and Kashmir),
 Zojila pass, Shipkila pass (Himachal Pradesh), Bomdila pass (Arunachal Pradesh),
 Nathula pass and Jhelepla pass (Sikkim).
 The Khyber Pass which connects Pakistan and Afganisthan.
 Bolan Pass in Pakistan.
3. The Outer Himalayas/the Siwaliks
 The Siwaliks extend from Jammu and Kashmir to Assam.
 It is partly made by the debris brought by the Himalayan Rivers.
 Average elevation, of this range is 1000 m.
 The longitudinal valleys found between the Siwaliks and the Lesser Himalayas are called
Duns in the west and Duars in the east.
 These are the ideal sites for the development of settlements in this region.
Purvanchal Hills
 These are the eastern off-shoot of Himalayas.

 Most of these hills are located along the border of India and Myanmar while others are
inside India.
 Dafla Hills, Abor Hills, Mishmi Hills, Patkai Bum Hills, Naga Hills, Manipur Hills, Mizo Hills,
Tripura Hills, Mikir Hills, Garo Hills, Khasi Hills and Jaintia Hills are the hills which are
collectively known as purvanchal Hills.
Importance of Himalayas
 Himalayas blocks southwest monsoon winds and causes heavy rainfall to north India.
 It forms a natural barrier to the sub-continent.
 It is the source for many perennial rivers like Indus, Ganges, Brahmaputra etc.
 Many hill stations and pilgrim centres like Amarnath, Kedarnath, Badrinath and
Vaishnavidevi temples are situated here.
 It prevents the cold winds blowing from the central Asia and protects India from severe
cold.
 Himalayas are renowned for the rich biodiversity.
The Great Northern Plains
This plain is one of the most extensive stretches of the alluvium in the world and is deposited
by the rivers Indus, Ganga, Brahmaputra and their tributaries
The Bhabar Plain

 This plain is made up of gravels and unassorted sediments deposited by the Himalayan
rivers.
 The porosity of this plain is so high that most of the small streams flow over this region
disappear.
The Tarai Tract
It is a zone of excessive dampness, thick forests and rich wild life.

The Bhangar Plains
The Bhangar represent the upland alluvial tracts of the Great Plains of India, formed by the
older alluviums.
The Khadar Plains
 The new alluvium tracts along the courses of the rivers are known as the ‘Khadar’ or
‘Bet’ lands.
 The Khadar tracts are enriched by fresh deposits of silt every year during rainy seasons.
Delta
 Triangle shaped fertile land at the mouth of Ganga and Brahmaputhra rivers is called as
the Sundarban delta.
 It is the biggest and fastest growing delta.
 The deltaic plain consists mainly of old mud, new mud and marsh. In the delta region,
the uplands are called ‘Chars’ while the marshy areas are called ‘Bils’.
Rajasthan Plains: 
 There are several salt lakes in Rajasthan.
 The Sambhar salt lake (Pushkar Lake) near Jaipur is the prominent one.
The Punjab – Haryana plains
The Punjab – Haryana plains are formed by the deposition of the rivers Sutlej, Beas and Ravi.
Ganga Plains: It extends from the Yamuna River in the west to Bangladesh in the east. The total
area covered by this plain is about 3.75 sq.km.
Brahmaputra Plains: 
It covers an area of about 56,275 sq.km. These plains create alluvial fans and marshy tracts.
The Peninsular Plateaus

 The plateau region lies to the south of the Great Northern Plains.
 It covers an area of about 16 lakh sq.km (about half of the total area of the country)
 The peak of Anaimudi is the highest point in the plateau. Its height is 2,695 m
Central Highlands
 The Central Highlands extend between the river Narmada and the Northern Great
Plains.
 Gurushikhar with 1,722 m is the highest peak of this range
 The eastern part of the Central High lands which lies in the north-eastern part of the
Indian Plateau is known as Chhota-Nagpur Plateau.
Deccan Plateau
 This physiographic division is the largest part of the plateau region of India.
 The shape of this plateau is roughly triangular
The Western Ghats
 The Western Ghats forms the western edge of the Peninsular Plateau.
 It runs parallel to the Arabian Sea coast.
 The northern part of this range is called as Sahyadris.
 The height of the Sahyadris increases from north to south.
The Eastern Ghats

 Eastern Ghats run from southwest to northeast form the eastern edge of this Plateau.
 This range is also called as Poorvadri.
The Coastal Plains
 The Peninsula Plateau of India is flanked by narrow coastal plains of varied width from
north to south.
 They were formed by the depositional action of the rivers and the erosional and
depositional actions of the sea-waves.
 The Indian coastal plains are divided into two divisions:
 The Western Coastal Plains
 The Eastern Coastal Plains.

The Western Coastal Plain
 It lies between the Western Ghats and the Arabian Sea.
 It extends from Rann of kutch in the north to Kanyakumari in the south and its width
varies from 10 to 80 km.
 It is mainly characterized by sandy beaches, coastal sand dunes, mud flats, lagoons,
estuary, laterite platforms and residual hills.
 Konkan Plain : The northern part of the West Coastal Plain
 Kanara: The middle part of this plain.
 Malabar Coast: The southern part of the plain is about 550 km long and 20-100 km
wide.
 This part of the coast is characterized by sand dunes. Along the coast, there are
numerous shallow lagoons and backwaters called Kayals and Teris.
 Vembanad: Famous back water lake found in this region.
The Eastern Coastal Plain
 It lies between the Eastern Ghats and the Bay of Bengal and, stretches along the states
of West Bengal, Odisha, Andhra Pradesh and Tamil Nadu.
 These plains are formed by the alluvial fillings of the littoral zone by the east flowing
rivers of India.
 The coastal plain consists mainly of the recent alluvial deposits. This coastal plain has a
regular shoreline with well-defined beaches.
 Northern Circars: The coastal plain between Mahanadi and Krishna river
 Coromandel coast: between Krishna and Kaveri rivers
 Among the backwater lakes of this coast, lake Chilika (Odisha) is the largest lake in India
located to the southwest of the Mahanadi delta

 Kolleru Lake : between the deltas of Godavari and Krishna
 The Pulicat Lake: the border of Andhra Pradesh and Tamil Nadu
Beaches
India is a country with 7517 km long coastline comprising the most beautiful beaches bounded
by Arabian Sea and Bay of Bengal.
Beaches, State & Geographical features
 Dhanushkodi- Tamil Nadu
 Turquoise blue sea water
 Varkala Beach- Kerala
 Sea Cliffs for wonderful sunset views
 Tarkarli Beach –Maharashtra
 Coral reefs and marine adventure
 OM Beach- Karnataka
 Two semi circular caves that join together forming the inverted symbol of OM
 Aguda Beach- Goa
 A huge hill dominates the southern side of the beach.
 Marari Beach- Kerala
 Saddle like rock(Hammock) Beach
Islands
 An island is a landmass surrounded by water on all sides.
 Islands may be formed Most of the oceanic islands are volcanic in origin.
 Group of islands formed by subduction of ocean plate are known as archipelago. Islands
of Japan form an archipelago.
 Marine organisms, the coral polyps colonize the tropical warm water and form islands
known as coral islands.

The Islands India has two major island groups namely
Andaman and Nicobar and Lakshadweep
Andaman and Nicobar Islands
 Andaman and Nicobar Islands are of volcanic origin.
 These islands are located in an elevated portion of the submarine mountains.
 Since these islands lie close to the equator, the climate remains hot and wet throughout
the year and has dense forests.
 The former group consists of 572 islands and are located in Bay of Bengal

 Area 8,249 sq.km.
 Capital Port Blair
 The entire group of islands is divided into two.
 They are Andaman in the north
 25 are inhabited
 The Nicobar in the south.
 13 are inhabited
 The Ten Degree Channel separates Andaman from Nicobar group.
 The southernmost tip, the Indira Point is a part of Nicobar Island.
 India’s only active volcano is found on Barren Island in Andaman and Nicobar group of
Islands.
Lakshadweep Islands
 This is a small group of coral islands located off the west coast of India.
 Literally means one lakh islands
 27 islands and are located in Arabian Sea.
 11 are inhabited.
 Area 32 sq. km.
 Capital Kavaratti
 Lakshadweep islands are separated from the Maldive Islands by the Eight Degree
Channel.
 The uninhabited “Pitt Island” of this group has a bird sanctuary.
 Earlier, it had three divisions namely Laccadive, Minicoy and Amindivi. It was named as
Lakshadweep in 1973.
Offshore Islands
 Besides the two group of islands, India has a number of islands along the Western Coast,

 Eastern Coast, in the delta region of Ganga and in the Gulf of Mannar.
 Islands administered by the adjacent states.

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