PHYSIOGRAPHY OF INDIA
On the basis of physiographic features, India may be divided into four major physiographic provinces :
The Northern Mountains
This region marked by the lofty ranges of Himalayas extends all along the Northern frontiers of the country, from eastern boundary of Pakistan to borders of Myanmar.
The Greater Himalaya/Himadri
- This is the most continuous, loftiest and northern most range of Himalayas.
- It has a core of Archaean rocks flogged by Metamorphous-sedimentary rocks.
- The average height of Himadri is 6100 metres.
- Most of peaks exceed 8000 m, such as Mount Everest-8848 m (the highest peak in the world). Kanchanjunga 8598m, Makalu - 8481m, Dhaula-giri-8172 m, etc.
- This range is penetrable through some passes existing at very high altitude.
- They are Burzil and Zozila in Kashmir, Baralapchala and Shipkila in Himachal Pradesh, Phagala, Niti Pass and Lipu Lakh Pass in Uttaranchal and Nathula and Jelepla in Sikkim.
- The Himadri runs in arc shape to a length of 2500 km from Nanga Parbat in the west to Namcha-Bawa in cast.
- There exists a number of glaciers of which Gangotri, Milan (Kumaun) and Zemu (Sikkim) are important.
- Between Himadri & Himachal exists the famous valley of Kashmir.
The Lesser Himalaya/Himachal/Middle Himalaya
- To the south of greater Himalaya lies the middle Himalaya which is sepa-rated from the Shivalik range in south through the Main Boundary Thrust (MBT).
- It comprises parallel ranges in Nepal and Punjab but of scattered moun-tains in Kumaun, the Dhauladhar, Pir-Panjal, Nag Tiba, Mahabharata and Mussourie range.
- Pir Panjal range of Kashmir is longest one running for 400 km between Jhelum and Beas.
- Shimla, Ranikhct, Chakrate, Mussouric, Nainital, Almora, Darjeeling, Dalhousie, etc., arc situated over the lesser Himalaya.
- The famous hill-resort of Shimla is situated on Dhauladhar range.
- Between Pir-Panjal and Zaskar range of main Himalayas lies the famous valley of Kashmir.
- The Kangra valley in Himachal Pradesh extends from foot of the Dhaulad-har range to south to Beas river. Kangra valley is a strike valley.
- Kullu valley is a transverse valley in upper course of Ravi river. Eastward of this lies the Kathmandu valley in Nepal.
- Steep bare southern slopes and gentle forests covered northern slopes of Himachal present a typical hogback topography.
- Along slopes of lesser Himalaya are found a number of small pastless, called merg in Kashmir (Gulmerg, Sonmerg, Tanmerg) and Bugyal and Payar in Uttaranchal.
The Outermost/Shivalik Himalaya
- The Shivalik comprises the southern most range of Himalayas.
- This chain of hills runs almost parallel to the lesser Himalayas for a dis-tance of about 2400 km from the Patwar plateau to Brahmaputra valley.
- The altitude varies from 600 to 1500 km.
- The Shivaliks are formed of great thickness of Mio-Plcistoccnc sands gravels and conglomerates which have been brought by the river flowing from the higher ranges of Himalayas.
- It has been folded, faulted and elevated during earth movements of Mioccne to Pleistocene period.
- The width of Shivaliks varies from 50 km in H.P. to 15 km in Arunachal Pradesh.
- These arc called Jammu hills in Jammu and Dafla, Miri, Abor and Mishmi hills in Arunachal Pradesh.
- The Dundwa range of Uttaranchal and Churia-Muria hills of Nepal arc also part of it.
- Between Shivalik and the Himachal (Middle Himalaya) there are some flat floored structural valleys, known as Doons.
- The Doons are intensively cultivated and densely populated e.g. Dchradun, Patlidun etc.
- These Doons in the east are known as Duars.
The Trans Himalayas (Tibetan Himalayas)
- It consists mainly at Karakoram, Laddakh and Kailash ranges.
- The range acts as a water divide between rivers draining into bay of Bengal and into the Tibetan lakes.
- Karakoram range determines India's frontiers with Afghanistan and China.
- The Laddakh plateau lies to north-cast Karakoram range and highest plateau lies to north-east Karakoram range.
- It has been dissected into a number of plains and mountains, the important ones being Soda plains, Aksai, China, Depsang plains, etc.
The Eastern Hills or Purvanchal
- After crossing the Dihang gorge the Himalaya takes a sudden southward turn and forms a series of comparatively low hills called Purvanchal.
- In the north is Patkaibum which forms the international boundary between Arunachal Pradesh and Myanmar.
- It merges into Naga hills southwards where Saramati is highest peak.
- To its west is Kohima hills whose highest peak is Japvo. T. South of Naga hills are Manipur hills forming boundary between Manipur & Myanmar.
- The Barail range separates Naga hills from Manipur hills.
- South of Manipur hills are Mizo hills whose highest point is Blue Mountain.
- Dapha-Bum is the highest peak of Mishmi hills.
- Mizo hills are the southernmost part of the north-eastern range.
Regional Division of Himalayas
- This 560 km long stretch of the Himalayas lies between the Indus and Satluj rivers.
- Karakoram, Laddakh, Pir-Panjal, Zaskar and Dhauladhar arc the main ranges of this section while Zozila is the major pass.
The Kumaun Himalayas
- It lies between the Satluj and Kali rivers.
- General elevation is higher than Punjab Himalayas.
- Nanda Devi, Kamet, Badrinath, Kedarnath, Gangotri are all important peaks.
- Nainital and Bhimtal are important lake regions.
- This section of Himalayas is situated between the Kali and Tista river.
- Mount Everest, Kanchanzunga, Makalu, Dhaulagiri, etc., are located in this region.
- The Himalayan ranges from Tista to Brahmaputra rivers arc included in the Assam Himalayas.
- The important peaks of this region are Namcha-l3awa, Kula-Kangri, etc.