142-771: Indian Mountaineering Foundation is an apex national body which organize and support, mountaineering and rock climbing expeditions at high altitudes in the Himalayas . The organization also promotes and encourages schemes for related adventure activities and environment-protection work in the Indian Himalayas . IMF has organized many expeditions to the high peaks in the Himalayas including Mount Everest . The first ascent of Mount Everest in 1953 by Sir Edmund Hillary and Tenzing Norgay generated interest in mountaineering in India which led to
284-408: A distinctive composition or mode or origin. Special names still in wide use include amphibolite, greenschist , phyllite, marble, serpentinite , eclogite, migmatite , skarn , granulite , mylonite, and slate. The basic classification can be supplemented by terms describing mineral content or texture. For example, a metabasalt showing weak schistosity might be described as a gneissic metabasalt, and
426-451: A distinctive layering called foliation (derived from the Latin word folia , meaning "leaves"). Foliation develops when a rock is being shortened along one axis during recrystallization. This causes crystals of platy minerals, such as mica and chlorite , to become rotated such that their short axes are parallel to the direction of shortening. This results in a banded, or foliated, rock, with
568-629: A large part of the Earth's crust and form 12% of the Earth's land surface. They are classified by their protolith, their chemical and mineral makeup, and their texture . They may be formed simply by being deeply buried beneath the Earth's surface, where they are subject to high temperatures and the great pressure of the rock layers above. They can also form from tectonic processes such as continental collisions, which cause horizontal pressure, friction, and distortion. Metamorphic rock can be formed locally when rock
710-510: A location is dependent on the season, orientation and bearing with respect to the Sun , and the mass of the mountain. As the Sun is the major contributor to the temperature, it is often directly proportional to the received radiation from the Sun with faces receiving more sunlight having a higher heat buildup. In narrow valleys between steep mountain faces, the weather conditions may differ significantly on both
852-464: A marble will not be identical with the amphibolite facies of a pelite. However, the facies are defined such that metamorphic rock with as broad a range of compositions as is practical can be assigned to a particular facies. The present definition of metamorphic facies is largely based on the work of the Finnish geologist, Pentti Eskola , with refinements based on subsequent experimental work. Eskola drew upon
994-522: A metamorphic rock to be classified in this manner, the protolith should be identifiable from the characteristics of the metamorphic rock itself, and not inferred from other information. Under the British Geological Survey's classification system, if all that can be determined about the protolith is its general type, such as sedimentary or volcanic, the classification is based on the mineral mode (the volume percentages of different minerals in
1136-438: A notable increase in the rate of glacier retreat across the region as a result of climate change. The rate of retreat varies across regions depending on the local conditions. Since 1975, a marked increase in the loss of glacial mass from 5–13 Gt/yr to 16–24 Gt/yr has been observed with an estimated 13% overall decrease in glacial coverage in the Himalayas. The resulting climate variations and changes in hydrology could affect
1278-413: A pelite containing abundant staurolite might be described as a staurolite pelite. [REDACTED] A metamorphic facies is a set of distinctive assemblages of minerals that are found in metamorphic rock that formed under a specific combination of pressure and temperature. The particular assemblage is somewhat dependent on the composition of that protolith, so that (for example) the amphibolite facies of
1420-519: A relatively mild grade of metamorphism, at temperatures of 350–500 °C (662–932 °F) and pressures of 200–500 MPa (2,000–5,000 bar). They can be divided into a lower group of metabasalts, including rare meta komatiites ; a middle group of meta-intermediate-rock and meta-felsic-rock; and an upper group of metasedimentary rock. The greenstone belts are surrounded by high-grade gneiss terrains showing highly deformed low-pressure, high-temperature (over 500 °C (932 °F)) metamorphism to
1562-410: A variety of metamorphic facies. Where subduction is taking place, the basalt of the subducting slab is metamorphosed to high-pressure metamorphic facies. It initially undergoes low-grade metamorphism to metabasalt of the zeolite and prehnite-pumpellyite facies , but as the basalt subducts to greater depths, it is metamorphosed to the blueschist facies and then the eclogite facies . Metamorphism to
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#17331069301731704-805: Is a mountain range in Asia, separating the plains of the Indian subcontinent from the Tibetan Plateau . The range has several peaks exceeding an elevation of 8,000 m (26,000 ft) including Mount Everest , the highest mountain on Earth. The mountain range runs for 2,400 km (1,500 mi) as an arc from west-northwest to east-southeast at the northern end of the Indian subcontinent. The Himalayas occupy an area of 595,000 km (230,000 sq mi) across six countries – Afghanistan , Bhutan , China , India , Nepal , and Pakistan . The sovereignty of
1846-417: Is a great variety of metamorphic rock types. In general, if the protolith of a metamorphic rock can be determined, the rock is described by adding the prefix meta- to the protolith rock name. For example, if the protolith is known to be basalt , the rock will be described as a metabasalt. Likewise, a metamorphic rock whose protolith is known to be a conglomerate will be described as a metaconglomerate . For
1988-530: Is also prized for building construction and as a medium for sculpture. On the other hand, schist bedrock can pose a challenge for civil engineering because of its pronounced planes of weakness. Metamorphic rocks form one of the three great divisions of rock types. They are distinguished from igneous rocks , which form from molten magma , and sedimentary rocks , which form from sediments eroded from existing rock or precipitated chemically from bodies of water. Metamorphic rocks are formed when existing rock
2130-652: Is also the source of major streams of the Ganges river system. The Eastern Himalayas form the eastern most stretch of the range and consist of the states of parts of Tibet in China, Sikkim , Assam , Arunachal Pradesh , parts of other North East Indian states and north West Bengal in India, entirety of Bhutan, mountain regions of central and eastern Nepal, and most of the western lowlands in Nepal. The eastern Himalayas broadly consists of two regions–the western Nepal Himalayas and
2272-507: Is among the highest in the world, at typically around 5,500 m (18,000 ft) while several equatorial mountains such as in New Guinea , the Rwenzoris , and Colombia , have a snow line at 900 m (3,000 ft) lower. As the physical features of mountains are irregular, with broken jagged contours, there can be wide variations in temperature over short distances. The temperature at
2414-474: Is amongst the most affected regions due to climate change . Since the late 20th century, scientists have reported a notable increase in the rate of glacier retreat and changes occurring at a far rapid rate. As per a 2019 assessment, the Himalayan region, which had experienced a temperature rise of 0.1 °C (32.2 °F) per decade was warming at an increased rate of 0.1 °C (32.2 °F) per decade over
2556-426: Is called a paired metamorphic belt . The main islands of Japan show three distinct paired metamorphic belts, corresponding to different episodes of subduction. Metamorphic rock is also exposed in metamorphic core complexes , which form in region of crustal extension. They are characterized by low-angle faulting that exposes domes of middle or lower crust metamorphic rock. These were first recognized and studied in
2698-464: Is dominated by metamorphic rock that has reached the amphibolite facies. Within the upper crust, which is the only part of the Earth's crust geologists can directly sample, metamorphic rock forms only from processes that can occur at shallow depth. These are contact (thermal) metamorphism , dynamic (cataclastic) metamorphism , hydrothermal metamorphism , and impact metamorphism . These processes are relatively local in occurrence and usually reach only
2840-484: Is followed by monsoon rains from June to September. The post monsoon season is largely devoid of rain and snow before beginning of cold winters in December-January with intermediate spring before the summer. There are localised wind pressure systems at high altitudes resulting in heavy winds. Due to its high altitude, the range blocks the flow of cold winds from the north into the Indian subcontinent. This causes
2982-476: Is formed as tectonic plates move apart. Hydrothermal metamorphism is extensive here. This is characterized by metasomatism by hot fluids circulating through the rock. This produces metamorphic rock of the greenschist facies. The metamorphic rock, serpentinite , is particularly characteristic of these settings, and represents chemical transformation of olivine and pyroxene in ultramafic rock to serpentine group minerals. Contact metamorphism takes place when magma
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#17331069301733124-585: Is found in the mixed deciduous and conifer forests of the Eastern Himalayas and the Himalayan water shrew are found on the river banks. The forests of the foothills are inhabited by several different primates, including the endangered Gee's golden langur and the Kashmir gray langur , within highly restricted ranges in the east and west of the Himalayas, respectively. The yaks are large domesticated cattle found in
3266-464: Is heated by the intrusion of hot molten rock called magma from the Earth's interior. The study of metamorphic rocks (now exposed at the Earth's surface following erosion and uplift) provides information about the temperatures and pressures that occur at great depths within the Earth's crust. Some examples of metamorphic rocks are gneiss , slate , marble , schist , and quartzite . Slate and quartzite tiles are used in building construction. Marble
3408-544: Is home to more than a billion people. In 2011, the population in the Himalayan region was estimated to be about 52.8 million with the combined drainage basin of the Himalayan rivers home to nearly 600 million. Of this, 7.96 million (15.1% of the total Himalayan population) live in Eastern Himalayas, 19.22 million in Central Himalayas (36.4%), and 25.59 million reside in Western Himalayas (48.5%). The population of
3550-403: Is injected into the surrounding solid rock ( country rock ). The changes that occur are greatest wherever the magma comes into contact with the rock because the temperatures are highest at this boundary and decrease with distance from it. Around the igneous rock that forms from the cooling magma is a metamorphosed zone called a contact aureole . Aureoles may show all degrees of metamorphism from
3692-405: Is known as burial metamorphism . This tends to produce low-grade metamorphic rock. Much more common is metamorphic rock formed during the collision process itself. The collision of plates causes high temperatures, pressures and deformation in the rocks along these belts. Metamorphic rock formed in these settings tends to shown well-developed schistosity. Metamorphic rock of orogenic belts shows
3834-599: Is one of the youngest mountain ranges on the planet and consists of uplifted sedimentary and metamorphic rock . According to the modern theory of plate tectonics , it was formed as a result of a continental collision and orogeny along the convergent boundary between the India and Eurasian Plates . During the Jurassic period (201 to 145 mya ), the Tethys Ocean formed the southern border of then existent Eurasian landmass. When
3976-451: Is subjected to temperatures greater than 150 to 200 °C (300 to 400 °F) and, often, elevated pressure of 100 megapascals (1,000 bar ) or more, causing profound physical or chemical changes. During this process, the rock remains mostly in the solid state, but gradually recrystallizes to a new texture or mineral composition. The protolith may be an igneous , sedimentary , or existing metamorphic rock. Metamorphic rocks make up
4118-506: Is sufficiently hard and dense that it is difficult to quarry. However, some quartzite is used as dimension stone , often as slabs for flooring, walls, or stairsteps. About 6% of crushed stone, used mostly for road aggregate, is quartzite. Marble is also prized for building construction and as a medium for sculpture. Schistose bedrock can pose a challenge for civil engineering because of its pronounced planes of weakness. A hazard may exist even in undisturbed terrain. On August 17, 1959,
4260-580: Is the lower middle sub-section of the Himalayas. It extends almost along the entire length of the Himalayas and is about 75 km (47 mi) wide. It is mostly composed of rocky surfaces and has an average elevation of 3,700–4,500 m (12,100–14,800 ft). The Greater Himalayas (also known as Himadri ) form the highest section of the Himalayas and extend for about 2,300 km (1,400 mi) from northern Pakistan to northern Arunachal Pradesh in India. The sub-range has an average elevation of more than 6,100 m (20,000 ft) and contains many of
4402-545: Is transformed physically or chemically at elevated temperature, without actually melting to any great degree. The importance of heating in the formation of metamorphic rock was first noted by the pioneering Scottish naturalist, James Hutton , who is often described as the father of modern geology. Hutton wrote in 1795 that some rock beds of the Scottish Highlands had originally been sedimentary rock but had been transformed by great heat. Hutton also speculated that pressure
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4544-400: Is uncertain. Special classifications exist for metamorphic rocks with a volcaniclastic protolith or formed along a fault or through hydrothermal circulation . A few special names are used for rocks of unknown protolith but known modal composition, such as marble, eclogite , or amphibolite . Special names may also be applied more generally to rocks dominated by a single mineral, or with
4686-426: Is used only when very little else is known about the rock that would allow a more definite classification. Textural classifications may be prefixed to indicate a sedimentary protolith ( para- , such as paraschist) or igneous protolith ( ortho- , such as orthogneiss). When nothing is known about the protolith, the textural name is used without a prefix. For example, a schist is a rock with schistose texture whose protolith
4828-475: Is usually devoid of schistosity and forms a tough, equigranular rock. If the rock was originally banded or foliated (as, for example, a laminated sandstone or a foliated calc- schist ) this character may not be obliterated, and a banded hornfels is the product. Contact metamorphism close to the surface produces distinctive low-pressure metamorphic minerals, such as spinel , andalusite, vesuvianite , or wollastonite . Similar changes may be induced in shales by
4970-470: Is very low in silica) to metafelsic-rock (with a high silica content). Where the mineral mode cannot be determined, as is often the case when rock is first examined in the field , then classification must be based on texture. The textural types are: A hornfels is a granofels that is known to result from contact metamorphism. A slate is a fine-grained metamorphic rock that easily splits into thin plates but shows no obvious compositional layering. The term
5112-742: The Andaman Sea . The Salween , Mekong , Yangtze , and Yellow Rivers all originate from parts of the Tibetan Plateau, north of the great water divide. These are considered distinct from the Himalayan watershed and are known as circum-Himalayan rivers. The Himalayan region has multiple lakes across various elevations including endorheic freshwater and saline lakes . The geology of the lakes vary across geographies depending on various factors such as altitude, climate, water source, and lithology . Tarns are high altitude mountain lakes situated above 5,500 m (18,000 ft) and are formed primarily by
5254-566: The Basin and Range Province of southwestern North America, but are also found in southern Aegean Sea , in the D'Entrecasteaux Islands , and in other areas of extension. Continental shields are regions of exposed ancient rock that make up the stable cores of continents. The rock exposed in the oldest regions of shields, which is of Archean age (over 2500 million years old), mostly belong to granite-greenstone belts. The greenstone belts contain metavolcanic and metasedimentary rock that has undergone
5396-559: The Bay of Bengal were also formed as a result of the same tectonic processes that formed the Himalayas. The Indian plate continues to be driven horizontally at the Tibetan Plateau at about 67 mm (2.6 in) per year, forcing it to continue to move upwards. About 20 mm (0.79 in) per year is absorbed by thrusting along the Himalaya southern front , which leads to the Himalayas rising by about 5 mm (0.20 in) per year. This makes
5538-639: The Dihang River to the India-Tibet border. The highest peak is the eastern anchor Namcha Barwa at 7,756 m (25,446 ft). The region is the source of many of the tributaries of the Brahmaputra River and consists of major mountain passes such as Nathu La , and Jelep La . Beyond the Dihang valley, the mountains extend as Purvanchal mountain range across the eastern boundary of India. The Himalayan range
5680-485: The Everest . At lower altitudes, the temperature is pleasantly warm during the summers. During winters, the low-pressure weather systems from the west cause heavy snowfall . There are two periods of precipitation with most of the rainfall occurring during the post summer season and moderate amount during the winter storms. The Himalayan range obstructs the path of the south west monsoon winds, causing heavy precipitation on
5822-734: The Indian epic Mahabharata , which is the personification of the Hindu deity Himavan . The mountain range is known as Himālaya in Hindi and Nepali (both written हिमालय ), Himalaya ( ཧི་མ་ལ་ཡ་ ) in Tibetan , Himāliya ( سلسلہ کوہ ہمالیہ ) in Urdu , Himaloy ( হিমালয় ) in Bengali , and Ximalaya ( simplified Chinese : 喜马拉雅 ; traditional Chinese : 喜馬拉雅 ; pinyin : Xǐmǎlāyǎ ) in Chinese . It
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5964-515: The Indian subcontinent and the regions north of the range. The mountains are spread across more than eight degrees of latitude and hence includes a wide range of climatic zones including sub-tropical , temperate , and semi-arid . The climate in a region is determined by factors such as altitude, latitude, and the impact on monsoon. There are generally five seasons: summer, monsoon, autumn or post-monsoon, winter, and spring. The summer in April-May
6106-590: The Kashmir valley . The higher elevations consist of rock fragements and lithosols with very low humus content. The Himalayas and the Central Asian mountain ranges consist of the third-largest deposit of ice and snow in the world, after the Antarctic and Arctic regions. It is often referred to as the "Third Pole" as it encompasses about 15,000 glaciers, which store about 12,000 km (2,900 cu mi) of fresh water. The South Col and Khumbu Glacier in
6248-505: The Kumaon region. The northern extremes of the Great Himalayas in Kashmir and Ladakh receive only 3–6 in (76–152 mm) of rainfall per year. During the winter season, a high pressure system develops over Central Asia, which results in winds flowing towards the Himalayas. However, due to the presence of less water bodies in the Central Asian region, the moisture content is low. As
6390-610: The Kumaon region in Himachal Pradesh and Uttarakhand in India, Indo-European speakers such as the Kanet and Khasi reside in the lower altitudes along with descendants of migrants from Tibet, who speak Tibeto-Burman languages, in the Kalpa and Lahul-Spiti regions. Metamorphic Metamorphic rocks arise from the transformation of existing rock to new types of rock in a process called metamorphism . The original rock ( protolith )
6532-1177: The Main Frontal Thrust and the Main Boundary Thrust (MBT); the Lesser Himalayan Zone between the MBT and the Main Central Thrust (MCT); the Higher Himalayan Zone beyond the MCT; the Tethyan Zone, separated by the South Tibetan Detachment System; and the Indus-Tsangpo Suture Zone, where the Indian plate is subducted below the Asian plate. The Arakan Yoma highlands in Myanmar and the Andaman and Nicobar Islands in
6674-474: The Mount Everest region are amongst the world's highest glaciers. The Gangotri which is 32 km (20 mi) long and is one of the largest glaciers, is one of the sources of the Ganges . The Himalayan glaciers show considerable variation in the rate of descent. The Khumbu moves about 1 ft (0.30 m) daily compared to certain other glaciers which move about 6 ft (1.8 m) per day. During
6816-450: The Paris agreement , aimed at climate change mitigation and adaptation . The actions are aimed at reducing emissions , increase the usage of renewable energy , and sustainable environmental practices. As the local population increasingly experience the impact of the changes in climate such as variations in temperature and precipitation, and change in vegetation, they are forced to adapt for
6958-703: The Sivalik Hills on the south; the Lower Himalayas ; the Great Himalayas , which is the highest and central range; and the Tibetan Himalayas on the north. The Sivalik Hills form the lowest sub-Himalayan range and extends for about 1,600 km (990 mi) from the Teesta River in the Indian state of Sikkim to northern Pakistan. The name derives from Sanskrit meaning "Belonging to Shiva ", which
7100-529: The Western Himalayas has characteristics of species from Central Asia and Mediterranean region. Fossils of species such as giraffe , and hippopotamus have been found in the foothills, suggesting the presence of African species some time ago. Large mammals such as Indian elephant , and Indian rhinoceros are confined to the densely forested moist ecosystems in the Eastern and Central Himalayas. Many of
7242-464: The Yarlung Tsangpo River . The Himalayas consists of four parallel mountain ranges: the Sivalik Hills on the south; the Lower Himalayas ; the Great Himalayas , which is the highest and central range; and the Tibetan Himalayas on the north. The range varies in width from 350 km (220 mi) in the north-west to 150 km (93 mi) in the south-east. The Himalayan range is one of
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#17331069301737384-507: The Zanskar , Pir Panjal Ranges , and parts of the Sivalik and Great Himalayas. The western anchor Nanga Parbat is the highest point in the region at 8,126 m (26,660 ft). It is also referred Punjab, Kashmir or Himachal Himalyas from west to east locally. The central Himalayas or Kumaon extend for about 320 km (200 mi) along the state of Uttarakhand in northern India from
7526-450: The atoms and ions in solid crystals to migrate, thus reorganizing the crystals, while high pressures cause solution of the crystals within the rock at their point of contact. Metamorphic rocks are characterized by their distinctive mineral composition and texture. Because every mineral is stable only within certain limits, the presence of certain minerals in metamorphic rocks indicates the approximate temperatures and pressures at which
7668-402: The crystallization of igneous rocks. They are stable at high temperatures and pressures and may remain chemically unchanged during the metamorphic process. Metamorphic rocks are typically more coarsely crystalline than the protolith from which they formed. Atoms in the interior of a crystal are surrounded by a stable arrangement of neighboring atoms. This is partially missing at the surface of
7810-616: The last ice age , there was a connected ice stream of glaciers between Kangchenjunga in the east and Nanga Parbat in the west. The glaciers joined with the ice stream network in the Karakoram in the west, the Tibetan inland ice in the north, and came to an end below an elevation of 1,000–2,000 m (3,300–6,600 ft) in the south. While the current valley glaciers of the Himalaya reach at most 20–32 km (12–20 mi) in length, several of
7952-410: The 18th century till the independence of the constituent states in the mid 20th century. The long history along with various outside influences have resulted in the mixture of various traditions and existence of wide range of ethnicity in the region. People speak various languages belonging to four principal language families– Indo-European , Tibeto-Burman , Austroasiatic , and Dravidian , with
8094-617: The Brahmaputra river system from the Tibetan rivers to the north. There are 19 major rivers in the Himalayas which form part of the two major river systems of Ganges - Brahmaputra , which follow an easterly course and Indus , which follows a north-westerly course. The northern slopes of Gyala Peri and the peaks beyond the Tsangpo drain into the Irrawaddy River , which originates in eastern Tibet and flows south through Myanmar to drain into
8236-420: The Himalayan lakes present the danger of a glacial lake outburst flood as they have grown considerably over the last 50 years due to glacial melting. While these lakes support a range of ecosystems and local communities, many of them remain poorly studied in terms of their hydrology and biodiversity. Due to its location and size, the Himalayas acts as a climatic barrier which affects the weather conditions of
8378-413: The Himalayan region geologically active and the movement of the Indian plate into the Asian plate makes the region seismically active, leading to earthquakes from time to time. The northern slopes of the Himalayas have a thicker soil cover than the southern slopes due to presence of lesser number of rivers and streams. These soils are loamy and are dark brown in colour, and are covered with forests in
8520-585: The Himalayan region including Bhutan, Nepal, Bangladesh, India, and Pakistan are amongst the most vulnerable countries in the Global South due to climate change. The temperature rise increases the incidence of tropical diseases such as malaria , and dengue further north. The extreme weather events might cause physical harm directly and indirectly due to lack of access and contamination of drinking water , pollution , exposure to chemicals, and destruction of crops, and drought . The climate change also impact
8662-613: The Himalayan region occurred in 2000 BCE when Aryans came from Central Asia and progressively settled along the plains to the south. Information on the Aryan culture in the region is found in Hindu literature such as the Vedas , and Puranas . Since the second century BCE, the Silk Road in China was connected to the Indian subcontinent by various routes running along the Himalayan region. The northern side of
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#17331069301738804-433: The Himalayan waters. The extremes of high altitude favor the presence of extremophile organisms, which include various species of insects such as spiders , and mites . The Himalayan fauna include endemic plants and animals and critically endangered or endangered species such as Indian elephant, Indian rhinoceros, musk deer and hangul . There are more than 7,000 endemic plants and 1.9% of global endemic vertebrates in
8946-426: The Himalayas has grown considerably over the last five decades from 19.9 million in 1961 with the annual growth rate (3.31%) more than three times higher than the world average (1.1%) during the same period. The earliest tribes in the Himalayas might have originated from Dravidian people from the south of the Indian subcontinent as evidenced by the presence of Dravidian languages . The major human migration towards
9088-447: The Himalayas reduce by 2 °C (36 °F) for every 300 m (980 ft) increase of altitude. Higher altitudes invariably experience low temperatures. In the Eastern Himalayas, Darjeeling at an altitude of 1,945 m (6,381 ft) has an average minimum temperature of 11 °C (52 °F) during the month of May, while the same has been recorded as −22 °C (−8 °F) at an altitude of 5,000 m (16,000 ft) on
9230-570: The Himalayas was under the influence of various Tibetan kingdoms across history. In the middle ages , the southern side came under the influence of various Rajput kings and later under the Mughal rule . Nepal was ruled by various kingdoms from both the Indian and Tibetan regions, until it was conquered by the Gurkha kingdom in the early 18th century. Most of the southern region came under the British influence in
9372-819: The Indian Himalayas. Pangong Lake spread across India and China is the highest saline lake in the world at an altitude of 4,350 m (14,270 ft) and amongst the largest in the region with a surface area of 700 km (270 sq mi). Spread across 189 km (73 sq mi), Wular Lake is amongst the largest fresh water lakes in Asia. Other large lakes include Tso Moriri , and Tso Kar in Ladakh , Nilnag , and Tarsar Lake , in Jammu and Kashmir , Gurudongmar , Chholhamu , and Tsomgo Lakes in Sikkim , Tilicho , Rara , Phoksundo , and Gokyo Lakes in Nepal. Some of
9514-594: The Sutlej River in the east to the Kali River in the west. The region comprises parts of Sivalik and Great Himalayas. At lower elevations below 2,400 m (7,900 ft), the region has a temperate climate and consists of permanent settlements. At elevations higher than 4,300 m (14,100 ft), permanent snow caps cover the Great Himalayas with the highest peaks being Nanda Devi at 7,817 m (25,646 ft) and Kamet at 7,756 m (25,446 ft). The region
9656-411: The Tethys ocean. The upliftment of the Himalayas occurred gradually and as the Great Himalayas became higher, they became a climatic barrier and blocked the winds, which resulted in lesser precipitation on the upper slopes. The lower slopes continued to be eroded by the rivers, which flowed in the gaps between the mountains and the folded lower Shivalik Hills and the Lesser Himalayas were formed due to
9798-419: The Tibetan Himalayas and the plateau beyond. It also played a role in the formation of Central Asian deserts such as the Taklamakan and Gobi . The monsoon is triggered by the different rates of heating and cooling between the Indian Ocean and Central Asia, which create large differences in the atmospheric pressure prevailing above each. As the Central Asian landmass heats up during the summer compared to
9940-534: The Western Himalayas. The high altitude mountainous areas are mostly barren or, at the most, sparsely sprinkled with stunted bushes. The Himalayas are home to various medicinal plants such as Abies pindrow used to treat bronchitis , Andrachne cordifolia used for snake bites , and Callicarpa arborea used for skin diseases . Nearly a fifth of the plant species in the Himalayas are used for medicinal purposes. Climate change , illegal deforestation , and introduction of non native species have had an effect on
10082-427: The amphibolite or granulite facies. These form most of the exposed rock in Archean cratons. The granite-greenstone belts are intruded by a distinctive group of granitic rocks called the tonalite - trondhjemite - granodiorite or TTG suite. These are the most voluminous rocks in the craton and may represent an important early phase in the formation of continental crust. Mid-ocean ridges are where new oceanic crust
10224-455: The animal species found in the region are unique and endemic or nearly endemic to the region. Other large animal species found in the Himalayas include Asiatic black bear , clouded leopard , and herbivores such as bharal , Himalayan tahr , takin , Himalayan serow , Himalayan musk deer , and Himalayan goral . Animals found at higher altitudes include brown bear , and the elusive snow leopard , which mainly feed on bharal. The red panda
10366-404: The bands showing the colors of the minerals that formed them. Foliated rock often develops planes of cleavage . Slate is an example of a foliated metamorphic rock, originating from shale , and it typically shows well-developed cleavage that allows slate to be split into thin plates. The type of foliation that develops depends on the metamorphic grade. For instance, starting with a mudstone ,
10508-691: The bend of the Indus River along the Pakistan-Afghanistan border region in the north-west to the Satlej river basin in India in the south-east. Most of the region lies in the Kashmir territory disputed between India and Pakistan with certain portions of the Indian state of Himachal Pradesh . The Indus forms the division between the Western Himalayas and the Karakoram range to the north. The Western Himalayas include
10650-420: The bulk composition of a rock. Hot fluids circulating through pore space in the rock can dissolve existing minerals and precipitate new minerals. Dissolved substances are transported out of the rock by the fluids while new substances are brought in by fresh fluids. This can obviously change the mineral makeup of the rock. However, changes in the mineral composition can take place even when the bulk composition of
10792-399: The burning of coal seams. This produces a rock type named clinker . There is also a tendency for metasomatism between the igneous magma and sedimentary country rock, whereby the chemicals in each are exchanged or introduced into the other. In that case, hybrid rocks called skarn arise. Dynamic (cataclastic) metamorphism takes place locally along faults . Here intense shearing of
10934-702: The campus of Indian Mountaineering Foundation in New Delhi , India. The festival is directed by Maninder Kohli, son of the legendary Himalayan mountaineer, Capt. Mohan Singh Kohli who was a member of India's first expedition to the summit of Everest in 1965. Capt. Mohan Kohli was the President of the Indian Mountaineering Foundation from 1989 to 1993. Himalayas The Himalayas , or Himalaya ( / ˌ h ɪ m ə ˈ l eɪ . ə , h ɪ ˈ m ɑː l ə j ə / HIM -ə- LAY -ə, hih- MAH -lə-yə )
11076-435: The circulation of fluids through buried rock, to the list of processes that help bring about metamorphism. However, metamorphism can take place without metasomatism ( isochemical metamorphism ) or at depths of just a few hundred meters where pressures are relatively low (for example, in contact metamorphism ). Metamorphic processes change the texture or mineral composition of the metamorphosed rock. Metasomatism can change
11218-510: The cold winds from Central Asia , and plays a significant roles in influencing the monsoons . The vast size, varying altitude range, and complex topography of the Himalayas result in a wide range of climates, from humid and subtropical to cold and dry desert conditions. The mountains have profoundly shaped the cultures of South Asia and Tibet . Many Himalayan peaks are considered sacred across various Indian and Tibetan religions such as Hinduism , Buddhism , Jainism , and Bon . Hence,
11360-427: The collision of tectonic plates at convergent boundaries . Here formerly deeply buried rock has been brought to the surface by uplift and erosion. The metamorphic rock exposed in orogenic belts may have been metamorphosed simply by being at great depths below the Earth's surface, subjected to high temperatures and the great pressure caused by the immense weight of the rock layers above. This kind of regional metamorphism
11502-449: The condensation occurs at higher altitudes in the north, there is more precipitation in the Great Himalayas in the west during the winter rains and the precipitation reduces towards the east. In January, the Kumaon region receives about 3 in (76 mm) of rainfall compared to about 1 in (25 mm) in the Eastern Himalayas. The Himalayan region has a highly sensitive ecosystem and
11644-491: The contact area to unmetamorphosed (unchanged) country rock some distance away. The formation of important ore minerals may occur by the process of metasomatism at or near the contact zone. Contact aureoles around large plutons may be as much as several kilometers wide. The term hornfels is often used by geologists to signify those fine grained, compact, non-foliated products of contact metamorphism. The contact aureole typically shows little deformation, and so hornfels
11786-612: The crystal, producing a surface energy that makes the surface thermodynamically unstable. Recrystallization to coarser crystals reduces the surface area and so minimizes the surface energy. Although grain coarsening is a common result of metamorphism, rock that is intensely deformed may eliminate strain energy by recrystallizing as a fine-grained rock called mylonite . Certain kinds of rock, such as those rich in quartz, carbonate minerals , or olivine, are particularly prone to form mylonites, while feldspar and garnet are resistant to mylonitization. Many kinds of metamorphic rocks show
11928-467: The downwarping of the intermediate lands. Minor streams ran between the faults within the mountains until they joined the major river systems in the plains. Intermediate valleys such as Kashmir and Kathmandu were formed from temporary lakes that were formed during pleistocene , which dried up later. The Himalayan region is made up of five geological zones– the Sub-Himalayan Zone bound by
12070-504: The eastern Assam Himalayas. The Nepal Himalayas forms the centre of the Himalayan curve and extend for 800 km (500 mi) between the Kali and Teesta Rivers . The Great Himalayas in the region form the highest part of the entire Himalayas and consist of many of the eight-thousanders including Everest, Kanchenjunga at 8,586 m (28,169 ft), and Makalu at 8,463 m (27,766 ft). These mountains host large glaciers that form
12212-423: The eclogite facies releases a great deal of water vapor from the rock, which drives volcanism in the overlying volcanic arc . Eclogite is also significantly denser than blueschist, which drives further subduction of the slab deep into the Earth's mantle . Metabasalt and blueschist may be preserved in blueschist metamorphic belts formed by collisions between continents. They may also be preserved by obduction onto
12354-495: The ecosystem. At higher altitudes, Eastern and Western Himalayan subalpine conifer forests consisting of various conifers occur. Chir pine is the dominant species which occurs at elevations from 800–900 m (2,600–3,000 ft). Other species include Deodar cedar , which grows at altitudes of 1,900–2,700 m (6,200–8,900 ft), blue pine and morinda spruce between 2,200–3,000 m (7,200–9,800 ft). At higher altitudes, alpine shrubs and meadows occur above
12496-588: The establishment of Indian mountaineering Foundation. IMF was formed in 1957 as the Sponsoring Committee of the Cho Oyu Expedition. The foundation was registered on 3 November 1961 and the new building was inaugurated by Indira Gandhi in 1980, then Prime Minister of India. In 1959, the organization changed its name to the Sponsoring Committee of Everest Expedition and in the following year it
12638-417: The flora and fauna of the region. Changes might decrease the territory available for local wildlife and reduction in prey for the predators . This puts the animals in conflict with humans as humans might encroach animal territories and the animals might venture into human habitats for search of food, which might exacerbate the economic loss of the local population. The Himalayan nations are signatories of
12780-509: The flora of the range. The increase in temperature has resulted in shifting of various species to higher elevations, and early flowering and fruiting. Many of the animal species are from the tropics, which have adapted to the various conditions across the Himalayan range. Some of the species of the Eastern Himalayas are similar to those found in East and South East Asia , while the animals of
12922-437: The following sequence develops with increasing temperature: The mudstone is first converted to slate, which is a very fine-grained, foliated metamorphic rock, characteristic of very low grade metamorphism. Slate in turn is converted to phyllite , which is fine-grained and found in areas of low grade metamorphism. Schist is medium to coarse-grained and found in areas of medium grade metamorphism. High-grade metamorphism transforms
13064-405: The formation of the Tibetan plateau . During miocene (20 mya), the increasing collision between the plates resulted in the top layer of metamorphic rocks getting peeled, which moved southwards to form nappes with trenches in between. As the mountains received rainfall, the waters flowing down the mountains eroded and steepened the southern slopes. The silt deposited by these rivers and streams in
13206-449: The identical composition, Al 2 SiO 5 . Likewise, forsterite is stable over a broad range of pressure and temperature in marble , but is converted to pyroxene at elevated pressure and temperature in more silicate-rich rock containing plagioclase , with which the forsterite reacts chemically. Many complex high-temperature reactions may take place between minerals without them melting, and each mineral assemblage produced indicates
13348-452: The last ice age , and give rise to some of the world's major rivers such as the Indus , Ganges , and Tsangpo – Brahmaputra . Their combined drainage basin is home to nearly 600 million people including 52.8 million living in the vicinity of the Himalayas. The region is also home to many endorheic lakes. The Himalayas have a major impact on the climate of the Indian subcontinent. It blocks
13490-458: The livelihoods of the people in the Himalayas and the plains below. Despite its greater size, the Himalayas does not form a water divide across its span because of the multiple river systems that cut across the range. While the mountains were formed gradually, the rivers concurrently cut across deeper gorges ranging from 1,500–5,000 m (4,900–16,400 ft) in depth and 10–50 km (6.2–31.1 mi) in width. The actual water divide lies to
13632-437: The low-pressure facies, such as the hornfels and sanidinite facies . Most metamorphic rock is formed by regional metamorphism in the middle and lower crust, where the rock reaches the higher-pressure metamorphic facies. This rock is found at the surface only where extensive uplift and erosion has exhumed rock that was formerly much deeper in the crust. Metamorphic rock is extensively exposed in orogenic belts produced by
13774-577: The lower ranges on the southern slopes speak Indo-European languages. The inhabitants of the Western Himalayas include the Kashmiri people , who speak Kashmiri in the Vale of Kashmir and the Gujjar and Gaddi people , who speak Gujari and Gaddi respectively in the lower altitudes of Jammu and Himachal Pradesh in India. The last two are pastoral and nomadic people, who own flocks of cattle and migrate across
13916-468: The lowlands and grassland meadows in the mid altitudes. The composition and texture of the soils in the Himalayas also vary across regions. In the Eastern Himalayas , the wet soils has a high humus content conducive for growing tea . Podzolic soils occur in the eastern range of the Indus basin between the Indus and Shyok Rivers . The Ladakh region is generally dry with saline soil while fertile alluvial soils occur in select river valleys such as
14058-419: The main valley glaciers were 60–112 km (37–70 mi) long during the ice age. 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 would have been at least 7.0–8.3 °C (12.6–14.9 °F) colder than it is today. Since the late 20th century, scientists have reported
14200-469: The majority of the languages belonging to the first two categories. The Tibetan Himalayas are inhabited by Tibetan people , who speak Tibeto-Burman languages. The Great Himalayas are mostly inhabited by nomadic groups and tribes, with most of the population in Lesser Himalayas , and Shivalik Hills . People towards the Great Himalayas in the north parts mostly speak Tibeto-Burman, while populations in
14342-404: The margins. The mountains act as heat islands and heavier mountains absorb and retain more heat than the surroundings, and therefore influences the amount of heat needed to raise the temperature from the winter minimum to the summer maximum. However, soil temperatures mostly remain the same on both the sides of a mountain at altitudes higher than 4,500 m (14,800 ft). Temperatures in
14484-520: The north of the Himalayas with rivers flowing down both the sides of the mountains. Some of the major river systems and their drainage system outdate the formation of the mountains itself. The water divide is formed by the Karakoram and Hindu Kush ranges on the west and the Ladakh Range on the east, separating the Indus system from Central Asia. On the east, Kailas and Nyenchen Tanglha Mountains separate
14626-658: The northwest, which extend into Central Asia . Its western anchor Nanga Parbat lies south of the northernmost bend of the Indus river in Pakistan-administered Kashmir and its eastern anchor Namcha Barwa lies to the west of the great eastern bend of the Yarlung Tsangpo River in Tibet Autonomous Region of China . The Himalayas occupies an area of 595,000 km (230,000 sq mi) across six countries – Afghanistan , Bhutan , China, India , Nepal , and Pakistan . The sovereignty of
14768-436: The number of glacial lakes , some of which may be prone to dangerous floods. The region is expected to encounter continued increase in average annual temperature and 81% of the region's permafrost is projected to be lost by the end of the century. The increased warming and melting of snow is projected to accelerate the regional river flows until 2060 after which it would decline due to reduction in ice caps and glacier mass. As
14910-403: The ocean below, the difference in pressure creates a thermal low . The moist air from the ocean is pushed inwards towards the low pressure system causing the monsoon winds. It results in precipitation along the slopes due to the orographic effect as the air rises along the mountains and condenses. The monsoon begins at the end of May in the eastern fringes of the range and moves upwards towards
15052-460: The overriding plate as part of ophiolites . Eclogites are occasionally found at sites of continental collision, where the subducted rock is rapidly brought back to the surface, before it can be converted to the granulite facies in the hot upper mantle. Many samples of eclogite are xenoliths brought to the surface by volcanic activity. Many orogenic belts contain higher-temperature, lower-pressure metamorphic belts. These may form through heating of
15194-477: The past half a century. The average warm days and nights had also increased by 1.2 days and 1.7 nights per decade while the average cold days and nights had declined by 0.5 and 1 respectively. This has also prolonged the length of the growing season by 4.25 days per decade. The climate change might results in erratic rainfall, varying temperatures, and natural disasters like landslides , and floods . The increasing glacier melt had been followed by an increase in
15336-587: The precipitation is projected to increase concurrently, the annual river flows would be largely unaffected for the Eastern Himalayan rivers fed by monsoons, but would reduce the flows in the Western Himalayan rivers. Almost a billion people live on either side of the mountain and are prone to impact of the climate change. This includes the people who live in the mountains, who are more vulnerable due to temperature variations and other biota. Countries in
15478-460: The range in the Kashmir region is disputed among India, Pakistan, and China. It is bordered by the Karakoram and Hindu Kush ranges on the northwest, Tibetan Plateau in the north, and by the Indo-Gangetic Plain in the south. Its western anchor Nanga Parbat lies south of the northernmost bend of the Indus river and its eastern anchor Namcha Barwa lies to the west of the great bend of
15620-462: The range in the Kashmir region is disputed amongst India, Pakistan, and China. The range varies in width from 350 km (220 mi) in the north-west to 150 km (93 mi) in the south-east. The range has several peaks exceeding an elevation of 8,000 m (26,000 ft) including Mount Everest , the highest mountain on Earth at 8,848 m (29,029 ft). The Himalayas consist of four parallel mountain ranges from south to north:
15762-1029: The region tropical and subtropical , temperate , coniferous , and grasslands . Tropical and subtropical broadleaf forests are mostly constricted to the high temperature and humid regions in Eastern and Central Himalayas , and pockets of Kashmir in the west. There are about 4,000 species of Angiosperms with major vegetation include Dipterocarpus , and Ceylon ironwood on porous soils at elevations below 2,400 m (7,900 ft) and oak , and Indian horse chestnut on lithosol between 1,100–1,700 m (3,600–5,600 ft). Himalayan subtropical pine forests with Himalayan screw pine trees occur above 4,000 m (13,000 ft) and Alder , and bamboo are found on terrains with higher gradient. Temperate forest occur at altitudes between 1,400–3,400 m (4,600–11,200 ft) while moving from south-east to north-west towards higher latitude. Eastern and Western Himalayan broadleaf forests consisting of sal trees dominate
15904-777: The region. More than 800 species of birds have been recorded with a large number of species restricted to the Eastern Himalayas. Amongst the bird species found include magpies such as black-rumped magpie and blue magpie , titmice , choughs , whistling thrushes , and redstarts . Raptors include bearded vulture , black-eared kite , and Himalayan griffon . Snow partridge and Cornish chough are found at altitudes above 5,700 m (18,700 ft). The Himalayan lakes also serve as breeding grounds for species such as black-necked crane and bar-headed goose . There are multiple species of reptiles including Japalura lizards, blind snakes , and insects such as butterflies . Several fresh water fish such as Glyptothorax are found in
16046-491: The region. As of 2022 , there are 575 protected areas established by the nations in the Himalayan-Hindu Kush region, which account for 40% of the land area and 8.5% of the global protected area. There are also four biodiversity hotspots , 12 ecoregions , 348 key biodiversity areas, and six UNESCO World Heritage Sites in the region. The Himalayan region with the associated Indo-Gangetic Plain and Tibetan plateau
16188-475: The rock by ascending magmas of volcanic arcs, but on a regional scale. Deformation and crustal thickening in an orogenic belt may also produce these kinds of metamorphic rocks. These rocks reach the greenschist , amphibolite, or granulite facies and are the most common of metamorphic rocks produced by regional metamorphosis. The association of an outer high-pressure, low-temperature metamorphic zone with an inner zone of low-pressure, high-temperature metamorphic rocks
16330-421: The rock does not change. This is possible because all minerals are stable only within certain limits of temperature, pressure, and chemical environment. For example, at atmospheric pressure, the mineral kyanite transforms to andalusite at a temperature of about 190 °C (374 °F). Andalusite, in turn, transforms to sillimanite when the temperature reaches about 800 °C (1,470 °F). All three have
16472-423: The rock to gneiss , which is coarse to very coarse-grained. Rocks that were subjected to uniform pressure from all sides, or those that lack minerals with distinctive growth habits, will not be foliated. Marble lacks platy minerals and is generally not foliated, which allows its use as a material for sculpture and architecture. Metamorphic rocks are one of the three great divisions of all rock types, and so there
16614-495: The rock typically forms mylonites. Impact metamorphism is unlike other forms of metamorphism in that it takes place during impact events by extraterrestrial bodies. It produces rare ultrahigh pressure metamorphic minerals, such as coesite and stishovite . Coesite is rarely found in eclogite brought to the surface in kimberlite pipes , but the presence of stishovite is unique to impact structures. Slate tiles are used in construction, particularly as roof shingle. Quartzite
16756-407: The rock underwent metamorphism. These minerals are known as index minerals . Examples include sillimanite , kyanite , staurolite , andalusite , and some garnet . Other minerals, such as olivines , pyroxenes , hornblende , micas , feldspars , and quartz , may be found in metamorphic rocks but are not necessarily the result of the process of metamorphism. These minerals can also form during
16898-486: The rock). Metasedimentary rocks are divided into carbonate-rich rock (metacarbonates or calcsilicate-rocks) or carbonate-poor rocks, and the latter are further classified by the relative abundance of mica in their composition. This ranges from low-mica psammite through semipelite to high-mica pelite . Psammites composed mostly of quartz are classified as quartzite. Metaigneous rocks are classified similarly to igneous rocks, by silica content, from meta-ultramafic-rock (which
17040-488: The same. The Himalayan region belongs to the Indomalayan realm . The flora and fauna of the Himalayas vary broadly across regions depending on the climate and geology. The Himalayas are home to multiple biodiversity hotspots, and is home to an estimated 35,000+ species of plants and 200+ species of animals. An average of 35 new species have been found every year since 1998. There are four types of vegetation found in
17182-593: The same. This has led to increased awareness on the impact of climate change, and adaptations such as change in crop cycles , introduction of drought resistant crops, and plantation of new trees. This has also led to the construction of more dams , canals , and other water structures, to prevent flooding and aid in agriculture. New plantations on barren lands to prevent landslides, and construction of fire lines made of litter and mud to prevent forest fires have been undertaken. However, lack of funding, awareness, access to technology, and government policy are barriers for
17324-406: The sedimentary rock limestone and chalk change into larger crystals in the metamorphic rock marble . In metamorphosed sandstone, recrystallization of the original quartz sand grains results in very compact quartzite, also known as metaquartzite, in which the often larger quartz crystals are interlocked. Both high temperatures and pressures contribute to recrystallization. High temperatures allow
17466-412: The slopes and the plains below. The effect of Himalayas on the hydroclimate impacts millions in the plains as the variability in monsoon rainfall is the main factor behind wet and dry years. As the Himalayas force the monsoon winds to give up most of the moisture before ascending up, the winds became dry once its reaches the north of the mountains. This results in the dry and windy cold desert climate in
17608-447: The slopes based on seasons. Various ethnic people such as Ladakhi , Balti , and Dard live on the north of the Great Himalayas along the Indus basin in the Kashmir and Ladakh regions spread across India, Pakistan, and China. The Dard speak Dard , which is part of Indo-European languages, while the Balti and Lakadkhi people speak Balti , and Ladakhi , which are part of Tibeto-Burman. In
17750-417: The snow-melt of the glaciers. The lower altitude lakes are replenished by a combination of rains, underground springs, and streams. Large lakes in the Himalayan basin were formed in the holocene period, when water pooled in the faults and the water supply was subsequently cut off. There are more than 4500 high altitude lakes of which about 12 large lakes contribute to more than 75% of the total lake area in
17892-409: The source of various rivers of the Ganges - Brahmaputra river system. The high altitude regions are uninhabitable with few mountain passes inbetween that serve as crossovers with the human settlements in the lower valleys. The Assam Himalaya forms the eastern most sub-section that extends eastward for 720 km (450 mi) from the Indian state of Sikkim through Bhutan and north-east India past
18034-520: The summits of several peaks in the region such as Gangkhar Puensum , Machapuchare , and Kailash have been off-limits to climbers. The name of the range is derived from the Sanskrit word Himālay ( हिमालय ) meaning 'abode of snow'. It is a combination of the words him ( हिम ) meaning 'frost/cold' and ālay ( आलय ) meaning 'dwelling/house'. The name of the range is mentioned as Himavat ( Sanskrit : हिमवत्) in older literature such as
18176-569: The super-continent Gondwana broke up nearly 180 mya, the Indo-Australian plate slowly drifted northwards towards Eurasia for 130-140 million years. The Indian Plate broke up with the Australian Plate about 100 mya. The Tethys ocean constricted as the Indian plate moved gradually upward. As both the plates were made of continental crusts , which were less denser than oceanic crusts , the increased compressive forces resulted in folding of
18318-404: The temperatures and pressures at the time of metamorphism. These reactions are possible because of rapid diffusion of atoms at elevated temperature. Pore fluid between mineral grains can be an important medium through which atoms are exchanged. The change in the particle size of the rock during the process of metamorphism is called recrystallization . For instance, the small calcite crystals in
18460-604: The trees. The Eastern Himalayan alpine shrub and meadows extend between 3,200–4,200 m (10,500–13,800 ft) and the Western Himalayan alpine shrub and meadows occur at altitudes of 3,600–4,500 m (11,800–14,800 ft). Major vegetation include Juniperus , Rhododendron on rocky terrain facing the Sun, various flowering plants at high elevations, and mosses , and lichens in humid, shaded areas. Interspersed Grasslands occur at certain regions, with thorns and semi-desert vegetation at low precipitation areas in
18602-574: The tropical zone to extend farther north in South Asia than anywhere else in the world. The temperatures are more pronounced in the Brahmaputra valley in the eastern section as it lies at a lower latitude and due to the latent heat of the forced air from the Bay of Bengal which condenses before moving past the Namcha Barwa , the eastern anchor of the Himalayas. Due to this, the permanent snow line
18744-539: The trough between the Himalayas and the Deccan plateau formed the Indo-Gangetic Plain . About 0.6 mya in the pleistocene period, the Himalayas rose higher and became the highest mountains on Earth. In the northern Great Himalayas , new gneiss and granite formations emerged on crystalline rocks that gave rise to the higher peaks. The summit of Mount Everest is made of unmetamorphosed marine ordovician limestone with fossil trilobites , crinoids , and ostracods from
18886-533: The underlying rock bed. The thrust faults created between the folds resulted in granite and basalt rocks from the Earth's mantle protruding through the crust . During the paleogene period (about 50 mya), the Indian plate collided with the Eurasian plate after it completely closed the Tethys ocean gap. The Indian plate continued to subduct under the Eurasian plate over the next 30 million years that resulted in
19028-451: The use of granulite as a classification for rock metamorphosed to the granulite facies. Instead, such rock will often be classified as a granofels. However, this approach is not universally accepted. Metamorphic rocks make up a large part of the Earth's crust and form 12% of the Earth's land surface. The lower continental crust is mostly metamafic-rock and pelite which have reached the granulite facies . The middle continental crust
19170-456: The west in June and July. There is heavy precipitation in the east which reduces progressively towards the west as the air becomes drier. Cherrapunji in Eastern Himalayas is one of the wettest places on Earth with an annual precipitation of 428 in (10,900 mm). The average annual rainfall varies from 120 in (3,000 mm) in the Eastern Himalayas to about 120 in (3,000 mm) in
19312-477: The world's tallest peaks, including Everest. It is mainly composed of granite rocks. The Tibetan Himalayas (also known as Tethys ) form the northern most sub-range of the Himalayas in Tibet . Longitudinally, the range is broadly divided into three regions– western , central , and eastern . The Western Himalayas form the westernmost section of the range and extend for about 560 km (350 mi) from
19454-517: The youngest mountain ranges on Earth and is made up of uplifted sedimentary and metamorphic rocks. It was formed more than 10 mya due to the subduction of the Indian tectonic plate with the Eurasian Plate along the convergent boundary . Due to the continuous movement of the Indian plate, the Himalayas keep rising every year, making them geologically and seismically active. The mountains consist of large glaciers , which are remnants of
19596-561: The zonal schemes, based on index minerals, that were pioneered by the British geologist, George Barrow . The metamorphic facies is not usually considered when classifying metamorphic rock based on protolith, mineral mode, or texture. However, a few metamorphic facies produce rock of such distinctive character that the facies name is used for the rock when more precise classification is not possible. The chief examples are amphibolite and eclogite . The British Geological Survey strongly discourages
19738-513: Was changed to Sponsoring Committee for Mountaineering Expeditions . On 15 January 1961 it was established as the Indian Mountaineering Foundation with its headquarters in Mumbai , India. The IMF Mountain Film Festival is a mountain film festival organized by Indian Mountaineering Foundation, India. This competitive event showcases adventure films shot in the Himalayas. The film festival takes place at
19880-419: Was important in metamorphism. This hypothesis was tested by his friend, James Hall , who sealed chalk into a makeshift pressure vessel constructed from a cannon barrel and heated it in an iron foundry furnace. Hall found that this produced a material strongly resembling marble , rather than the usual quicklime produced by heating of chalk in the open air. French geologists subsequently added metasomatism ,
20022-466: Was mentioned as Himmaleh in western literature such as Emily Dickinson 's poetry and Henry David Thoreau 's essays. The Himalayas run as an arc for 2,400 km (1,500 mi) from west-northwest to east-southeast at the northern end of the Indian subcontinent , separating the Indo-Gangetic Plains from the Tibetan Plateau . It is bordered by the Karakoram and Hindu Kush ranges on
20164-528: Was originally used to denote the 320 km (200 mi) stretch from Haridwar to the Beas River . The range is about 16 km (9.9 mi) wide on average and the elevation ranges from 900–1,200 m (3,000–3,900 ft). It rises along the Indo-Gangetic Plain and is often separated from the higher northern sub-ranges by valleys. The eastern portion of the range is called Churia Range in Nepal. The Lower or Lesser Himalaya (also known as Himachal )
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