Indian Geography Notes

India Physiography – The Northern Mountains (Himalayas)

India can be divided into following physical divisions viz.

The Himalayan Mountains form the northern mountain region of India.
They are the highest mountain ranges in the world.
These mountain ranges start from Pamir Knot in the west and extend up to Purvanchal in the east.
Youngest & Loftiest mountain range of the world
Formed by Tectonic Forces & are 2400 Km in Length
Are of varying width → from 400 Km in Kashmir to 160 Km Arunachal Pradesh
Altitudinal variations are greater in the eastern part than in the western part
Prominent Features → Highest peaks, Deep valleys & Gorges, Glaciers etc.

The Himalayan Mountains can be further divided into following major ranges -

Trans Himalayas Immediate to the north of the Great Himalayan Range Most of the part of this Himalayan range lies in the Tibet and hence also called Tibetan Himalaya Ranges → Zaskar, K2 (Godwin Austin), Ladakh, Kailash and Karakoram Range	Greater Himalaya (Inner Himalaya) Always covered with snow → Known as Himadri Average height → 6000 mts Most continuous range Core composed of granite Ranges → Mt. Everest, Kanchenjunga Forests type → Needle leaved coniferous
Middle Himalaya Average height → 3500 – 4500 mts Most of the valleys & hill stations are located in this range e.g. Kashmir, Kathmandu , Nainital Ranges → Pir Panjal, Dhaula Dhar, Mahabharat Forests type → Broad leaved evergreen	Outer Himalaya (Shivalik Range/ Himachals) Average height → 600 – 1200 mts Most of the Dun & Duars are located in this range Ex. Dehradun, Patlidun (longitudinal valleys) Deciduous type forests

Brahmaputra marks the eastern border of the Himalayas.
Beyond the Dihang gorge, the Himalayas bend sharply towards south and form the Eastern hills or Purvanchal which run through the NE India & are mostly composed of sandstones
Mishmi hills, Patkai Hills, Naga Hills, Manipuri Hills and Mizo Hills

Punjab Himalayas / Kashmir Himalaya / Himachal Himalaya → Between the Indus and Sutlej
Kumaon Himalayas → Between Sutlej and Kali rivers
Nepal Himalayas → Between Kali and Tista rivers
Assam Himalayas → Between Tista and Dihang rivers

Strategic significance	Acts as a natural frontier of India with other countries (China, Pakistan, Afghanistan)
Climatic significance	Prevent further northward movement of summer monsoon and also prevent cold northern winds from Siberia to enter into India
Agricultural significance	Rivers from Himalayas deposits a lot of sediment on its foothold, from which are formed India’s most fertile agricultural grounds known as Northern plains
Economic significance	Huge hydro-electric power potential of Himalayan rivers + Himalayan timber + Himalayan Herbs & Medicinal plants
Tourism Significance	Comprises of Large ecological biodiversity, natural views & hill stations