Explore the majestic Himalayan Mountains. Learn about their fascinating origin that spans millions of years, and the diverse regions they encompass, from the Trans-Himalayas to the Shivaliks and Eastern Hills.
About the Himalayas
The Himalayan Mountains stand as a grand barrier guarding India’s frontiers against both cold winds arising from central Asia and foreign invasions from the central Asian rulers.
Additionally, they also act as a dividing range between the Tibetan Plateau in the North and the Alluvial Plains towards the South of it.
Along with acting as a water divide between Indo-Gangetic and Tibetan river systems, they also act as a cultural divide. The Himalayan range comprises a number of peaks and valleys. The world’s tallest mountain Mt. Everest is part of Himalayan range located in Nepal. A number of valleys like the Mussorie, Kashmir valley serve as residential areas as well as touristic destinations.
Formation of Himalayas
The origin of the Himalayan mountain range goes back several million years ago. Their formation is the result of a collision of two massive tectonic plates consisting of the Indian plate with the Eurasian (Asian) plate along the convergent boundary. The following series of events led to their genesis:
- Existence of Pangea and Panthalassa: The process started 250 million years ago. There existed a supercontinent called Pangea which was surrounded by a massive water body called Panthalassa.
- Breaking of Pangea: Around 150 million years ago the supercontinent Pangea began to break into different parts.
- Laurasia or Angaraland: In the first place Pangea was divided into two parts. The northern part of the Pangea was called Angaraland or Laurasia. It consisted of landmasses which contained present-day North America, Europe and Asia.
- Formation of Gondwana land: The southern part of the Pangea is called Gondwanaland. It consisted of the present-day South America, Africa, South India, Australia and Antarctica.
- Formation of Tethys Sea: Due to the breaking down of Pangea, a long narrow sea was created between Angaraland and Gondwanaland. This sea was known as the Tethys Sea and it occupied the area of the prevailing mountains. During the course of time huge amounts of sediments were deposited in the bed of the sea by the rivers from two landmasses.
- Breaking down of Gondwanaland: The Gondwanaland was further broken down into different smaller landmasses.
- Drift of Indo-Australian tectonic plate towards the north: The Indo-Australian tectonic plate which contained the continents of Australia and the Indian subcontinent drifted towards north by the convection currents generated in the Mantle of the Earth. For millions of years, India drifted across the sea toward the Eurasian plates (a portion of Angaraland).
- Shrinkage of Tethys Sea and formation of folds: As the Indian plate approached Asia, the area of the Tethys Sea began to shrink and the sediments in its seabed were slowly pushed upwards which led to the formation of folds. When the plate containing India and the plate containing Tibet collided, instead of descending with the plate, the comparatively light sedimentary rocks that make up the subcontinent of India pushed against Tibet and forced it upwards. This event led to the creation of one of the highest relief features on the Earth – The Himalayas.
- Formation of Islands: The Andaman and Nicobar Island chain in the Bay of Bengal and the Arakan Yoma in Myanmar were created as a consequence of this collision activity.
Division of Himalayas
On the basis of the latitudinal extent, the Himalayas can be divided into three divisions as follows:
- The Himalayan Mountain Ranges.
- The Eastern Hills or Purvanchal.
It is the name denoted to the Himalayan ranges which are north of the Great Himalayan range. They stretch into an east-west direction for a distance of about 1,000 km and the average elevation of the peaks is approximately 3000 metres above mean sea level. The Trans-Himalayas is constituted by various ranges such as Karakoram, Ladakh and Zanskar explained below:
- Karakoram Range: The northern-most range of the Trans-Himalayan in India is the Karakoram range. This particular range constitutes India’s boundary with Afghanistan and China. The average width of this range is 110-130 km. It is home to one of the highest peaks and some of the largest glaciers of the world like Siachen glacier, Remo glacier.
- Ladakh Range: It is considered as the south-eastern extension of the Karakoram Range. It extends towards the south-east from the mouth of the Shyok River in the northern areas of the Kashmir region to the border with the Tibet Autonomous Region of China. The climate of the region is semi arid and the vegetation is scanty and it is limited predominantly to short grasses. The Deosai Mountains, a range of mountains, situated towards the southwest of the Indus River in Pakistan Occupied Kashmir (POK), are occasionally considered as part of the Ladakh range. The Kailash range in the western Tibet is also considered a westward extension of the Ladakh range.
- Zaskar Range: It runs more or less parallel to the Great Himalayan range. This range extends south-east from the Suru River to the upper Karnali River. Kamet Peak (25,446 feet) is the highest peak in this range.
The Trans-Himalayan range contains some of the highest peaks of the world such as K2 (Mount Godwin Austen) 8611m, which is the second-highest peak in the world.
The Himalayan Mountain Ranges
The Himalayas are also known by various names such as Himadri, Himavan etc. The Himalayan ranges are bordered on the northwest by the Karakoram and Hindu Kush ranges, on the north by Tibetan plateau and the south by Indo-Gangetic plains.
- Extent: These are one of the largest mountain chains.
- The range of the main Himalayas alone stretches for a distance of over 2,400 km from the Indus gorge in the west to the Brahmaputra gorge in the east.
- The Himalayan mountain ranges are wider on the western side compared to the eastern side. The Himalayan boundary towards south is well defined by the foothills but the northern boundary is rather obscure and merges with the edge of the Tibet Plateau.
- Composition of the Himalayas: The Himalayan range is the youngest mountain range in the world and consists mostly of uplifted sedimentary and metamorphic rocks.
Classification of the Himalayan Mountain Ranges
These are further subdivided into Greater Himalayas, Inner or Middle Himalayas and Shiwalik.
- The Greater Himalayas
- They are also known as the Himadri, Inner or the Central Himalayas.
- These mountains are composed of Archaean rocks like granite, gneisses and the ancient schist.
- It extends towards south-east across the regions of northern Pakistan, northern India, and Nepal before curving eastwards across Sikkim and Bhutan and finally turning towards north-east across northern Arunachal Pradesh.
- They comprise several of the world’s highest mountains, such as Nanga Parbat, Mount Everest, Kanchenjunga and Namcha Barwa (from west to east). The orientation of slopes in this range is steep towards north and gentle towards south.
- Inner or Middle Himalayas:
- These mountain ranges have mean elevation of about 3,500 to 5,000 metres with an average breadth of 60 to 80 km.
- They are also called Lesser Himalayas or Lower Himalayas. It also consists of several important ranges such as, Nag Tibba, Mahabharat Range, Dhauladhar, the Pir Panjal and the Mussoorie Range.
- Various important rivers such as Jhelum and Chenab pass through this range.
- The famous Valley of Kashmir lies between Pir Panjal and Zanskar range, and the Jhelum river cuts beautifully through the Kashmir valley. The famous hill resorts like Shimla, Chail, Ranikhet, Chakrata, Nainital, Almora etc., lie in this range.
- Shiwalik or Outer Himalayas:
- It is the southernmost range and lies between the Great Plains of North India and the Middle Himalayas.
- Extent of the Shivaliks: The Shiwaliks are wider on western side compared to the eastern side. It rises abruptly from the plain of the Indus and Ganges rivers in the south and parallels the main range of the Himalayas in the north, from which it is separated by valleys. Nepal’s portion of the range is called the Churia Range.
- Formation of Doons: The Shiwaliks are also peculiar due to formation of doons. During the upliftments of the Shiwaliks, many rivers stopped forming temporary lakes. These rivers deposited the sediments at the bottom of the lakes. Over the period of time the river could cut through the Shiwalik therefore, water drained away leaving behind fertile alluvial soils known as Doons in the west and Duars in the eastern part of India. They are important for the cultivation of tea.
The Eastern Hills
Towards the region of Dihang Gorge, the Himalayas take a rapid southward turn because of Syntaxial Bend and form a series of relatively low hills. Collectively, these hills are also called Purvanchal as they are located in the eastern part of India.
- Extent: They extend from Arunachal Pradesh in the north to Mizoram in the south. These hills constitute India’s border with Myanmar.
- Patkai Bum – They are the northernmost range of Purvanchal. It forms the boundary between Arunachal Pradesh and Myanmar.
- Naga Hills – They lie to the south of Patkai Bum. They, along with Patkai Bum, form the watershed between India and Myanmar.
- Manipur Hills – They are situated to the south of Naga Hills. The Barail range splits the Naga Hills from the Manipur Hills.
- Mizo Hills or Lushai Hills – They lie to the south of Manipur Hills.
Regional Divisions of Himalayas
Based on longitudinal extent, the Himalayas has been divided into the following regional divisions:
- Punjab Himalayas
- It lies between the Indus river and Sutlej river. The majority of this region lies in the state of Jammu and Kashmir and Himachal Pradesh.
- Nearly, all the ranges such as Karakoram, Pir Panjal, Ladakh, Zaskar and Dhauladhar are prominent in this section. It is dominated by high snow covered mountains, deep gorges and high mountain passes.
- Kumaon Himalayas
- It is bounded by the Satluj and the Kali river. Several significant peaks such as Nanda Devi, Trisul, Kedarnath, Dunagiri, Kamet, Badrinath lie in this region. It is also known as Garhwal Himalayas in the west. This region is even more loftier when compared with Kashmir Himalayas. Major hill stations such as Nainital, Ranikhet and Almora lie in this region.
- Nepal Himalayas
- It stretches from Kali River in the west to Tista River in the east. A majority of this section lies in Nepal, therefore it is called Nepal Himalayas. This section is dominated by some of the tallest peaks of the world, including Mount Everest, Kanchenjunga, Dhaulagiri etc. Famous valley of Kathmandu is also located in this region.
- Assam Himalayas
- It is a sector of which lies between Tista and the Brahmaputra River. In India, it covers the states such as Assam and Arunachal Pradesh. However, this sector is much lower in elevation when compared to Nepal Himalayas.
- Namcha Barwa is the highest peak in this region. Other peaks include Gyala Peri, Kengto and Nyegyi Kangsang.
- They make a dramatic turn towards the south in the region of Arunachal Pradesh. Hence, ranges are arranged in the north-south trend in the north-eastern states.
Three Broad Divisions of Himalayas
- Western Himalayas
They spread over Jammu and Kashmir, Ladakh, Himachal Pradesh and Uttarakhand. It spreads over a distance of around 880 km between the Indus in the west and the Kali river in the east.
It consists of three physiographic provinces:
- Kashmir Himalayas (Union Territories of Jammu and Kashmir)
- Himachal Himalayas (Himachal Pradesh)
- Kumaon Himalayas (Uttarakhand)
Prominent Peaks: Godwin Austin or K2.
- Central Himalayas
They stretch for a distance of about 800 km between River Kali in the west and River Teesta in the east.
Prominent Peaks: Mt. Everest, Kanchenjunga, Makalu etc.
- Eastern Himalayas
These lie between the Teesta river in the west and Brahmaputra river in the east, stretching for a distance of about 720 km.
Prominent Peaks: Namcha Barwa
Syntaxial Bends of the Himalayas
At its western and eastern extremities, the east-west trend of Himalayan ranges is suddenly terminated and the continuous range takes a sharp turn southwards, which are called Syntaxial Bends of the Himalayas. The bends on the western end are called the western syntaxical band and those at the eastern end are called the eastern syntaxical band.
- Western Syntaxical bend: It occurs near the Nanga Parbat where the River Indus cut the deep gorge.
- Eastern Syntaxical bend: It occurs at the eastern extremity of the Himalayas. This turn is visible prominently in Arunachal Pradesh around the Namcha Barwa, where the mountain ranges turn southwards after crossing the Brahmaputra.
Comparison of Western and Eastern Himalayas
|The Western Himalayan ranges lie between the Indus river in the west and the Kali river (Nepal) in the east.
|The Eastern Himalayan range extends from the Tista river in the west to the easternmost extent of Himalayan ranges.
|In the portion of western Himalayan ranges, height is attained in the gradual succession as the mountains from the plains rise in a series of stages. Thus, the higher mountain ranges are far away from the plains.
|The Eastern Himalayan ranges rise abruptly from the plains, thus peaks are not very far away from the plains such as Kanchenjunga.
|The amount of rainfall in Western Himalayan ranges is less and is 1/4th of that of the Eastern Himalayan ranges.
Western Himalayan ranges receive precipitation from north-west in the winters.
|The Eastern Himalayan ranges face high rainfalls and they are covered with dense forests.
The Eastern Himalayan ranges receive precipitation from south-west monsoon in the summers.
|The alpine vegetation in Western Himalayan ranges is found up to 3000 m because of scant rainfall.
The dominant vegetation in the Western Himalayan ranges is coniferous forests and alpine vegetation.
|The alpine vegetation in Eastern Himalayan ranges is found up to 4000 m as a result of heavy rainfall.
The vegetation in eastern Himalayan ranges consists of Sal forest and evergreen trees along with foothills, temperate broadleaf forests and alpine forest.
|Western Himalayan ranges lack biodiversity.
|Eastern Himalayan ranges have huge biodiversity and are one of the Biodiversity Hotspots. Due to the presence of tropical evergreen forests there are high levels of biodiversity.
Significance of Himalayas
- Climatic Influence: These ranges significantly affect the climate of India. Owing to their high altitude, length and direction, they effectively interrupt the summer monsoons coming from the Bay of Bengal and Arabian Sea and trigger precipitation in the form of rain or snow. It also prevents cold winter winds from the Siberian region from entering India.
- Security: These ranges have been protecting India from outside forces and intruders since ancient times thus serving as a defence barrier for India. In spite of development in modern warfare knowledge, the defence implication of these cannot be overlooked altogether.
- Perennial Source of Water: The majority of large rivers of India have their sources in the mountains of the Himalayan ranges. Plentiful rainfall and vast snow-fields in the form of glaciers act as a feeding grounds for the mighty rivers flowing in India. The Himalayan Rivers, along with hundreds of their tributaries, form the footing of life in the entire north India.
- Forest Wealth: They host the base of a rich forest which provides fuel wood and a huge diversity of raw materials for forest based industries. In addition, they also host a huge inventory of medicinal plants and herbs. Besides, they also provide rich pasture grounds for cattle rearing.
- Agriculture: Though the Himalayan ranges do not provide extensive plains for agricultural activities, some of the slopes have been terraced for the cultivation. Rice is one of the main crops on the terraced slopes. The other crops are wheat, maize, potatoes, tobacco and ginger. Tea is a distinctive crop, which can be exclusively grown on the hill slopes. It also sustains the horticulture sector by providing a wide variety of fruits such as apples, pears, grapes, walnuts, cherries, peaches, apricots, etc.
- Minerals: The Himalayan region provides many valuable minerals. There is huge potential for mineral oil in the tertiary rocks of the Himalayan ranges. Anthracite is a superior type of coal that is found in the Kalakot region of Kashmir. The various important minerals such as copper, lead, zinc, nickel, cobalt, antimony, tungsten, gold, silver, limestone, semi-precious and precious stones, gypsum and magnetite are known to occur at many locations.
- Hydroelectricity: These mountain ranges hold a huge potential for Hydroelectricity due to its fast flowing rivers. The rugged topography provides natural terrain for waterfalls at various places. Moreover, dams can also be constructed across rivers at some other places. The huge hydropower potential of the Himalayan rivers has not been explored fully.