Himalayan Ranges – Greater, Middle, Shiwaliks
Himalayan Ranges: Greater Himalayas, Middle Himalayas, Shiwaliks, Trans-Himalayas & Purvanchal – for UPSC IAS.
Major Physical Divisions of India
- The Himalayan Mountains
- The Northern Plains
- The Peninsular Plateau
- The Indian Desert
- The Coastal Plains
- The Islands
Himalayas
- Includes the Himalayas, Purvanchal, and their extensions Arakan Yoma (Myanmar) and Andaman and Nicobar Islands (but we will consider these as islands only).
- It is the youngest and highly unstable landmass of India.
- Tectonic movements are very common.
Indo-Gangetic Plain
- Between Peninsular and Himalayan region.
- Most youthful, monotonous [lack of change or variety] region prone to tectonic forces.
Peninsular Plateau
- Includes the entire south India, central India, Aravalis, Rajmahal hills, Meghalaya plateau, Kuchchh-Kathiawar region (Gujarat) etc..
- It is the oldest and the most stable landmass of India.
Great Indian desert
- The Great Indian Desert is located in the western part of India.
- It is a dry, hot, and sandy stretch of land. It has very little vegetation.
Coastal Plains
- Eastern Coastal Plains and Western Coastal Plains.
- Formed due to consolidation of sediments brought by rivers (fluvial deposits).
- Highly stable just like peninsular plateau.
Indian Islands
- Two major groups – Lakshadweep and, Andaman and Nicobar islands.
- Lakshadweep are a group of atolls occupied by coral reefs. No significant volcanism or tectonic activity in the recent past. Highly vulnerable to sea-level rise.
- Andaman and Nicobar islands – Continuation of Arakan Yoma. Has active volcanoes and is tectonically active.
Division of the Himalayas
- Shiwaliks or outer Himalayas
- Lesser or Middle Himalayas
- The Greater Himalayas
- The Trans-Himalayas – Tibetan Himalayas.
- The Eastern Hills – Purvanchal: A chain of hills in North-East India.
Himalayan Ranges
- Series of several parallel or converging ranges.
- The ranges are separated by deep valleys creating a highly dissected topography.
- The southern slopes have steep gradients and the northern slopes have comparatively gentler slopes.
- Most of the Himalayan ranges fall in India, Nepal, and Bhutan. The northern slopes are partly situated in Tibet (trans-Himalayas) while the western extremity lies in Pakistan, Afghanistan, and Central Asia.
- The Himalayas between Tibet and Ganga Plain is a succession of three parallel ranges.
Shiwalik Range
- Also known as Outer Himalayas.
- Located in between the Great Plains and Lesser Himalayas.
- The altitude varies from 600 to 1500 meters.
- Runs for a distance of 2,400 km from the Potwar Plateau to the Brahmaputra valley.
- The southern slopes are steep while the northern slopes are gentle.
- The width of the Shiwaliks varies from 50 km in Himachal Pradesh to less than 15 km in Arunachal Pradesh.
- They are an almost unbroken chain of low hills except for a gap of 80-90 km which is occupied by the valley of the Tista River and Raidak River.
- Shiwalik range from North-East India up to Nepal are covered with thick forests but the forest cover decreases towards west from Nepal (The quantum of rainfall decreases from east to west in Shiwaliks and Ganga Plains).
- The southern slopes of the Shiwalik range in Punjab and Himachal Pradesh are almost devoid of forest cover. These slopes are highly dissected by seasonal streams called Chos.
- Valleys are part of synclines and hills are part of anticlines or antisynclines.
The Shiwaliks are known by different names in different areas
Region | Name of Shiwaliks |
Jammu Region | Jammu Hills |
Dafla, Miri, Abor and Mishmi Hills | Arunachal Pradesh |
The Dhang Range, Dundwa Range | Uttarakhand |
Churia Ghat Hills | Nepal |
Formation of Duns (Duras)
- Shiwalik Hills were formed by the accumulation of conglomerates (sand, stone, silt, gravel, debris, etc.).
- These conglomerates, in the initial stages of deposition, obstructed the courses of the rivers draining from the higher reaches of the Himalayas and formed temporary lakes.
- With the passage of time, these temporary lakes accumulated more and more conglomerates. The conglomerates were well settled at the bottom of the lakes.
- When the rivers were able to cut their courses through the lakes filled with conglomerate deposits, the lakes were drained away leaving behind plains called ‘duns’ or ‘doons’ in the west and ‘duars’ in the east.
- Dehra Dun in Uttarakhand is the best example.
- Kotah, Patli Kothri, Chumbi, Kyarda, Chaukhamba, Udhampur, and Kotli are other important duns.
Middle or the Lesser Himalaya
- In between the Shiwaliks in the south and the Greater Himalayas in the north.
- Runs almost parallel to both ranges.
- It is also called the Himachal or Lower Himalaya.
- Lower Himalayan ranges are 60-80 km wide and about 2400 km in length.
- Elevations vary from 3,500 to 4,500 m above sea level.
- Many peaks are more than 5,050 m above sea level and are snow-covered throughout the year.
- Lower Himalayas have steep, bare southern slopes (steep slopes prevent soil formation) and more gentle, forest-covered northern slopes.
- In Uttarakhand, the Middle Himalayas are marked by the Mussoorie and the Nag Tibba ranges.
- The Mahabharat Lekh, in southern Nepal, is a continuation of the Mussoorie Range
- East of the Kosi River, the Sapt Kosi, Sikkim, Bhutan, Miri, Abor, and Mishmi hills represent the lower Himalayas.
- The Middle Himalayan ranges are more friendly to human contact.
- The majority of the Himalayan hill resorts like Shimla, Mussoorie, Ranikhet, Nainital, Almora, and Darjeeling, etc. are located here.
Important ranges of Lesser Himalayas | Region |
The Pir Panjal Range | Jammu and Kashmir (They are to the south of Kashmir Valley) |
The Dhaola Dhar Range | Himachal Pradesh |
The Mussoorie Range and The Nag Tiba Range | Uttarakhand |
Mahabharat Lekh | Nepal |
The Pir Panjal range
- The Pir Panjal range in Kashmir is the longest and the most important range.
- It extends from the Jhelum river to the upper Beas river for over 300 km.
- It rises to 5,000 meters and contains mostly volcanic rocks.
Passes in Pir Panjal
- Pir Panjal Pass (3,480 m), the Bidil (4,270 m), Golabghar Pass (3,812 m) and Banihal Pass (2,835 m).
- The Banihal Pass is used by the Jammu-Srinagar highway and Jammu-Baramula railway.
- The Kishanganga, the Jhelum, and the Chenab cut through the range.
- Southeast of the Ravi, the Pir Panjal continues as Dhaola Dhar range, passing through Dalhousie, Dharmshala, and Shimla.
Important Valleys
- Between the Pir Panjal and the Zaskar Range of the main Himalayas, lies the valley of Kashmir.
- The synclinal basin of the valley is floored with alluvial, lacustrine [lake deposits], fluvial [river action], and glacial deposits.
- Jehlum River meanders through these deposits and cuts a deep gorge in Pir Panjal through which it drains. (Kashmir is like a basin with very few outlets)
- In Himachal Pradesh, there is Kangra Valley. It is a strike valley and extends from the foot of the Dhaola Dhar Range to the south of Beas.
- On the other hand, the Kulu Valley in the upper course of the Ravi is a transverse valley.
The Great Himalaya
- Also known as Inner Himalaya, Central Himalaya, or Himadri.
- The average elevation of 6,100 m above sea level and an average width of about 25 km.
- It is mainly formed of the central crystallines (granites and gneisses) overlain by metamorphosed sediments [limestone].
- The folds in this range are asymmetrical with a steep south slope and gentle north slope giving ‘hogback (a long, steep hill or mountain ridge)’ topography.
- This mountain arc convexes to the south just like the other two.
- Terminates abruptly at the syntaxial bends. One in the Nanga Parbat in the north-west and the other in the Namcha Barwa in the north-east.
- This mountain range boasts of the tallest peaks of the world, most of which remain under perpetual snow.
Regional name of Mount Everest | Region |
Sagarmatha (The Goddess of the Sky) | Nepal |
Chomlungma (Mother of the World) | China (Tibet) |
Passes in the Greater Himalayas
- The passes because they are generally higher than 4,570 m above sea level and are snowbound for most of the year.
State | Passes of Greater Himalayas |
Jammu and Kashmir | Burzil Pass Zoji La [La means pass] |
Himachal Pradesh | Bara Lacha La Shipki La |
Uttarakhand | Thaga La Niti Pass Lipu Lekh |
Sikkim | Nathu La Jelep La |
The Trans Himalayas
- The Himalayan ranges immediately north of the Great Himalayan range.
- Also called the Tibetan Himalaya because most of it lies in Tibet.
- The Zaskar, the Ladakh, the Kailas and the Karakoram are the main ranges.
- It stretches for a distance of about 1,000 km in the east-west direction.
- The average elevation is 3000 m above mean sea level.
- The average width of this region is 40 km at the extremities and about 225 km in the central part.
- The Nanga Parbat (8126 m) is an important range which is in The Zaskar Range.
- North of the Zaskar Range and running parallel to it is the Ladakh Range. Only a few peaks of this range attain heights of over 6000 meters.
- The Kailas Range (Gangdise in Chinese) in western Tibet is an offshoot of the Ladakh Range. The highest peak is Mount Kailas (6714 m). River Indus originates from the northern slopes of the Kailas range.
- The northernmost range of the Trans-Himalayan Ranges in India is the Great Karakoram Range also known as the Krishnagiri range.
- Karakoram Range extends eastwards from the Pamir for about 800 km. It is a range with lofty peaks [elevation 5,500 m and above]. It is the abode of some of the greatest glaciers of the world outside the polar regions.
- Some of the peaks are more than 8,000 meters above sea level. K2 (8,611 m)[Godwin Austen or Qogir] is the second highest peak in the world and the highest peak in the Indian Union.
- The Ladakh Plateau lies to the north-east of the Karakoram Range. It has been dissected into a number of plains and mountains {Soda Plains, Aksai Chin, Lingzi Tang, Depsang Plains, and Chang Chenmo}.
Purvanchal or Eastern Hills
- Eastern Hills or The Purvanchals are the southward extensions of the Himalayas running along the north-eastern edge of India.
- At the Dihang gorge, the Himalayas take a sudden southward bend and form a series of comparatively low hills which are collectively called as the Purvanchal.
- Purvanchal hills are convex to the west.
- They run along the India-Myanmar Border extending from Arunachal Pradesh in the north to Mizoram in the south.
- Patkai Bum hills are made up of strong sandstone; elevation varying from 2,000 m to 3,000 m; merges into Naga Hills where Saramati (3,826 m) is the highest peak.
- Patkai Bum and Naga Hills form the watershed between India and Myanmar.
- South of Naga Hills is the Manipur hills which are generally less than 2,500 meters in elevation.
- The Barail range separates Naga Hills from Manipur Hills.
- Further south the Barail Range swings to the west into Jaintia, Khasi, and Garo hills which are an eastward continuation of the Indian peninsular block. They are separated from the main block by Ganga and Brahmaputra rivers.
- South of the Manipur Hills is the Mizo Hills (previously known as the Lushai hills) which have an elevation of less than 1,500 meters. The highest point is the Blue Mountain (2,157 m) in the south.
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