The Himalayas, or Himalaya (/ˌhɪməˈleɪə, hɪˈmɑːləjə/; Sanskrit: IPA: [ɦɪmɐːləjɐː], himá 'snow,' ā-laya 'dwelling, abode'[1]) are a mountain range in Asia separating the plains of the Indian subcontinent from the Tibetan Plateau. The range has some of the planet's highest peaks, including the highest, Mount Everest. Over 100 peaks exceeding 7,200 m (23,600 ft) in elevation lie in the Himalayas. By contrast, the highest peak outside Asia (Aconcagua, in the Andes) is 6,961 m (22,838 ft) tall.[2]
The Himalayas abut or cross five countries: Bhutan, India, Nepal, China, and Pakistan. The sovereignty of the range in the Kashmir region is disputed between India, Pakistan, and China.[3] The Himalayan range is bordered on the northwest by the Karakoram and Hindu Kush ranges, on the north by the Tibetan Plateau, and on the south by the Indo-Gangetic Plain. Some of the world's major rivers, the Indus, the Ganges, and the Tsangpo-Brahmaputra, rise in the vicinity of the Himalayas, and their combined drainage basin is home to some 600 million people; 53 million people live in the Himalayas.[4] The Himalayas have profoundly shaped the cultures of South Asia and Tibet; many Himalayan peaks are sacred in Hinduism and Buddhism.
Lifted by the subduction of the Indian tectonic plate under the Eurasian Plate, the Himalayan mountain range runs west-northwest to east-southeast in an arc 2,400 km (1,500 mi) long.[5] Its western anchor, Nanga Parbat, lies just south of the northernmost bend of the Indus river. Its eastern anchor, Namcha Barwa, lies immediately west of the great bend of the Yarlung Tsangpo River. The range varies in width from 350 km (220 mi) in the west to 150 km (93 mi) in the east.[6]
The name of the range derives from the Sanskrit Himālaya (हिमालय 'abode of the snow'), from himá (हिम 'snow') and ā-laya (आलय 'receptacle, dwelling').[7] They are now known as "the Himalaya Mountains", usually shortened to "the Himalayas". Following the etymology some writers refer to it as the Himalaya. This was also previously transcribed as Himmaleh, as in Emily Dickinson's poetry[8] and Henry David Thoreau's essays.[9]
The mountains are known as the Himālaya in Nepali and Hindi (both written हिमालय), Himāl (हिमाल) in Kumaoni, the Himalaya (ཧི་མ་ལ་ཡ་) or 'The Land of Snow' (གངས་ཅན་ལྗོངས་) in Tibetan, the Himāliya Mountain Range (سلسلہ کوہ ہمالیہ) in Urdu, the Himaloy Parvatmala (হিমালয় পর্বতমালা) in Bengali and the Ximalaya Mountain Range (simplified Chinese: 喜马拉雅山脉; traditional Chinese: 喜馬拉雅山脉; pinyin: Xǐmǎlāyǎ Shānmài) in Chinese.
The name of the range is sometimes also given as Himavan in older writings
The Himalayas consist of parallel mountain ranges: the Sivalik Hills on the south; the Lower Himalayan Range; the Great Himalayas, which is the highest and central range; and the Tibetan Himalayas on the north.[11] The Karakoram are generally considered separate from the Himalayas.
In the middle of the great curve of the Himalayan mountains lie the 8,000 m (26,000 ft) peaks of Dhaulagiri and Annapurna in Nepal, separated by the Kali Gandaki Gorge. The gorge splits the Himalayas into Western and Eastern sections both ecologically and orographically – the pass at the head of the Kali Gandaki the Kora La is the lowest point on the ridgeline between Everest and K2 (the highest peak of the Karakoram range in Pakistan). To the east of Annapurna are the 8,000 m (5.0 mi) peaks of Manaslu and across the border in Tibet, Shishapangma. To the south of these lies Kathmandu, the capital of Nepal and the largest city in the Himalayas. East of the Kathmandu Valley lies the valley of the Bhote/Sun Kosi river which rises in Tibet and provides the main overland route between Nepal and China – the Araniko Highway/China National Highway 318. Further east is the Mahalangur Himal with four of the world's six highest mountains, including the highest: Cho Oyu, Everest, Lhotse and Makalu. The Khumbu region, popular for trekking, is found here on the south-western approaches to Everest. The Arun river drains the northern slopes of these mountains, before turning south and flowing to the range to the east of Makalu.
In the far east of Nepal, the Himalayas rise to the Kangchenjunga massif on the border with India, the third highest mountain in the world, the most easterly 8,000 m (26,000 ft) summit and the highest point of India. The eastern side of Kangchenjunga is in the Indian state of Sikkim. Formerly an independent Kingdom, it lies on the main route from India to Lhasa, Tibet, which passes over the Nathu La pass into Tibet. East of Sikkim lies the ancient Buddhist Kingdom of Bhutan. The highest mountain in Bhutan is Gangkhar Puensum, which is also a strong candidate for the highest unclimbed mountain in the world. The Himalayas here are becoming increasingly rugged with heavily forested steep valleys. The Himalayas continue, turning slightly northeast, through the Indian State of Arunachal Pradesh as well as Tibet, before reaching their easterly conclusion in the peak of Namche Barwa, situated in Tibet inside the great bend of the Yarlang Tsangpo river. On the other side of the Tsangpo, to the east, are the Kangri Garpo mountains. The high mountains to the north of the Tsangpo including Gyala Peri, however, are also sometimes included in the Himalayas.
Going west from Dhaulagiri, Western Nepal is somewhat remote and lacks major high mountains, but is home to Rara Lake, the largest lake in Nepal. The Karnali River rises in Tibet but cuts through the centre of the region. Further west, the border with India follows the Sarda River and provides a trade route into China, where on the Tibetan plateau lies the high peak of Gurla Mandhata. Just across Lake Manasarovar from this lies the sacred Mount Kailash in the Kailash Ranges, which stands close to the source of the four main rivers of Himalayas and is revered in Hinduism, Buddhism, Sufism, Jainism, and Bonpo. In the newly created Indian state of Uttarkhand, the Himalayas rise again as the Kumaon Himalayas[12] with the high peaks of Nanda Devi and Kamet. The state is also home to the important pilgrimage destinations of Chaar Dhaam, with Gangotri, the source of the holy river Ganges, Yamunotri, the source of the river Yamuna, and the temples at Badrinath and Kedarnath. Kumaon Himalayas is regionally divided into 2- Kumaon hills in Kumaon division and Garhwal hills in Garhwal division.[13]
The next Himalayan Indian state, Himachal Pradesh, is noted for its hill stations, particularly Shimla, the summer capital of the British Raj, and Dharmasala, the centre of the Tibetan community in exile in India. This area marks the start of the Punjab Himalaya and the Sutlej river, the most easterly of the five tributaries of the Indus, cuts through the range here. Further west, the Himalayas form most of the southern portion of Jammu and Kashmir and Ladakh, which are disputed between India and Pakistan but administered by India. The twin peaks of Nun Kun are the only mountains over 7,000 m (4.3 mi) in this part of the Himalayas. Beyond lies, the renowned Kashmir Valley and the town and lakes of Srinagar. Finally, the Himalayas reach their western end in the dramatic 8000 m peak of Nanga Parbat, which rises over 8,000 m (26,000 ft) above the Indus valley and is the most westerly of the 8000 m summits. The western end terminates at a magnificent point near Nanga Parbat where the Himalayas intersect with the Karakoram and Hindu Kush ranges, in the disputed Pakistani-administered territory of Gilgit-Baltistan
50 million years ago[14]
The Himalayan range is one of the youngest mountain ranges on the planet and consists mostly of uplifted sedimentary and metamorphic rock. According to the modern theory of plate tectonics, its formation is a result of a continental collision or orogeny along the convergent boundary (Main Himalayan Thrust) between the Indo-Australian Plate and the Eurasian Plate. The Arakan Yoma highlands in Myanmar and the Andaman and Nicobar Islands in the Bay of Bengal were also formed as a result of this collision.
During the Upper Cretaceous, about 70 million years ago, the north-moving Indo-Australian Plate (which has subsequently broken into the Indian Plate and the Australian Plate[15]) was moving at about 15 cm (5.9 in) per year. About 50 million years ago this fast-moving Indo-Australian Plate had completely closed the Tethys Ocean, the existence of which has been determined by sedimentary rocks settled on the ocean floor and the volcanoes that fringed its edges. Since both plates were composed of low density continental crust, they were thrust faulted and folded into mountain ranges rather than subducting into the mantle along an oceanic trench.[14] An often-cited fact used to illustrate this process is that the summit of Mount Everest is made of marine limestone from this ancient ocean.[16]
Today, the Indian plate continues to be driven horizontally at the Tibetan Plateau, which forces the plateau to continue to move upwards.[17] The Indian plate is still moving at 67 mm per year, and over the next 10 million years it will travel about 1,500 km (930 mi) into Asia. About 20 mm per year of the India-Asia convergence is absorbed by thrusting along the Himalaya southern front. This leads to the Himalayas rising by about 5 mm per year, making them geologically active. The movement of the Indian plate into the Asian plate also makes this region seismically active, leading to earthquakes from time to time.
During the last ice age, there was a connected ice stream of glaciers between Kangchenjunga in the east and Nanga Parbat in the west.[18][19] In the west, the glaciers joined with the ice stream network in the Karakoram, and in the north, they joined with the former Tibetan inland ice. To the south, outflow glaciers came to an end below an elevation of 1,000–2,000 m (3,300–6,600 ft).[18][20] While the current valley glaciers of the Himalaya reach at most 20 to 32 km (12 to 20 mi) in length, several of the main valley glaciers were 60 to 112 km (37 to 70 mi) long during the ice age.[18] The glacier snowline (the altitude where accumulation and ablation of a glacier are balanced) was about 1,400–1,660 m (4,590–5,450 ft) lower than it is today. Thus, the climate was at least 7.0 to 8.3 °C (12.6 to 14.9 °F) colder than it is today
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