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113-593: The geology of the Himalayas is a record of the most dramatic and visible creations of the immense mountain range formed by plate tectonic forces and sculpted by weathering and erosion . The Himalayas , which stretch over 2400 km between the Namcha Barwa syntaxis at the eastern end of the mountain range and the Nanga Parbat syntaxis at the western end, are the result of an ongoing orogeny —

226-616: A turbiditic environment, on the northern part of the Indian continental slope and in the adjoining Neotethys basin . The age of these sediments ranges from Late Permian to Eocene . The metamorphic rocks of the Himalaya can be very useful in deciphering and coming up with models of tectonic relationships. According to Kohn (2014), the exhumation of metamorphic rocks can be explained by the Main Himalayan Thrust. Although

339-630: A city in Perm Krai. The stage was introduced by Alexandr Antonovich Stukenberg in 1890. The Kungurian currently lacks a defined GSSP. Recent proposals have suggested the appearance of Neostreptognathodus pnevi as the lower boundary. The Guadalupian Series is named after the Guadalupe Mountains in Texas and New Mexico, where extensive marine sequences of this age are exposed. It was named by George Herbert Girty in 1902. The Roadian

452-685: A coal swamp community, has an upper canopy consisting of lycopsid tree Sigillaria , with a lower canopy consisting of Marattialean tree ferns, and Noeggerathiales. Early conifers appeared in the Late Carboniferous, represented by primitive walchian conifers, but were replaced with more derived voltzialeans during the Permian. Permian conifers were very similar morphologically to their modern counterparts, and were adapted to stressed dry or seasonally dry climatic conditions. The increasing aridity, especially at low latitudes, facilitated

565-405: A combination of these three mechanisms, it is nevertheless the last mechanism which created the high topographic relief of the Himalaya. The Himalayan tectonics result in long term deformation. This includes shortening across the Himalayas that range from 900 to 1,500 km. Said shortening is a product of the significant ongoing seismic activity. The continued convergence of the Indian plate with

678-604: A dramatic increase in diversification during the Early Permian. Towards the end of the Permian, there was a substantial drop in both origination and extinction rates. The dominant insects during the Permian Period were early representatives of Paleoptera , Polyneoptera , and Paraneoptera . Palaeodictyopteroidea , which had represented the dominant group of insects during the Carboniferous, declined during

791-532: A major rifting episode split Gondwana in two parts. The Indian continent became part of East Gondwana, together with Australia and Antarctica . However, the separation of East and West Gondwana, together with the formation of oceanic crust, occurred later, in the Callovian (160-155 Ma). The Indian plate then broke off from Australia and Antarctica in the Early Cretaceous (130-125 Ma) with

904-540: A peak of diversity in the Cisuralian, with a substantial decline during the Guadalupian-Lopingian following Olson's extinction, with the family diversity dropping below Carboniferous levels. Embolomeres , a group of aquatic crocodile-like limbed vertebrates that are reptilliomorphs under some phylogenies. They previously had their last records in the Cisuralian, are now known to have persisted into

1017-525: A protective cover, over plants such as ferns that disperse spores in a wetter environment. The first modern trees ( conifers , ginkgos and cycads ) appeared in the Permian. Three general areas are especially noted for their extensive Permian deposits—the Ural Mountains (where Perm itself is located), China, and the southwest of North America, including the Texas red beds. The Permian Basin in

1130-588: A single formation (a stratotype ) identifying the lower boundary of the stage. The ages of the Permian, from youngest to oldest, are: For most of the 20th century, the Permian was divided into the Early and Late Permian, with the Kungurian being the last stage of the Early Permian. Glenister and colleagues in 1992 proposed a tripartite scheme, advocating that the Roadian-Capitanian was distinct from

1243-689: Is a geologic period and stratigraphic system which spans 47 million years from the end of the Carboniferous Period 298.9 million years ago (Mya), to the beginning of the Triassic Period 251.902 Mya. It is the sixth and last period of the Paleozoic Era; the following Triassic Period belongs to the Mesozoic Era. The concept of the Permian was introduced in 1841 by geologist Sir Roderick Murchison , who named it after

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1356-642: Is a global hiatus in the terrestrial fossil record during the late Kungurian and early Roadian , referred to as "Olson's Gap" that obscures the nature of the transition. Other proposals have suggested that the North American and Russian records overlap, with the latest terrestrial North American deposition occurring during the Roadian, suggesting that there was an extinction event, dubbed " Olson's Extinction ". The Middle Permian faunas of South Africa and Russia are dominated by therapsids, most abundantly by

1469-538: Is at work while the mountains are being uplifted until the mountains are reduced to low hills and plains. The early Cenozoic uplift of the Rocky Mountains of Colorado provides an example. As the uplift was occurring some 10,000 feet (3,000 m) of mostly Mesozoic sedimentary strata were removed by erosion over the core of the mountain range and spread as sand and clays across the Great Plains to

1582-663: Is defined by the first appearance of the conodont Jinogondolella aserrata. The Capitanian is named after the Capitan Reef in the Guadalupe Mountains of Texas, named by George Burr Richardson in 1904, and first used in a chronostratigraphic sense by Glenister and Furnish in 1961 as a substage of the Guadalupian Stage. The Capitanian was ratified as an international stage by the ICS in 2001. The GSSP for

1695-631: Is divided into 4 parallel tectonostratigraphic zones and 5 thrust faults which extend across the length of Himalaya orogen. Each zone, flanked by the thrust faults on its north and south, has stratigraphy (type of rocks and their layering) different from the adjacent zones. From south to north, the zones and the major faults separating them are the Main Frontal Thrust (MFT), Subhimalaya Zone (also called Sivalik ), Main Boundary Thrust (MBT), Lesser Himalaya (further subdivided into

1808-461: Is measured to be approximately 17 mm/yr. This convergence is accommodated through seismic activity in active fault zones. As a result, the Himalayan range is one of the most seismically active regions in the world. This region has experienced many high magnitude earthquakes in the last 100 years, including the 1905 Kangra Earthquake , 1975 Kinnaur Earthquake , 1991 Uttarkashi Earthquake , and

1921-536: Is sometimes referred to as the Cis-Himalayan tectonic plate in the older literature. It forms the southern foothills of the Himalayan Range and is essentially composed of Miocene to Pleistocene molassic sediments derived from the erosion of the Himalaya. These molasse deposits, known as the " Murree and Sivaliks Formations" , are internally folded and imbricated . The Sub-Himalayan Range

2034-452: Is thought to have existed during the Early Permian. Though the fossil record is fragmentary, lungfish appear to have undergone an evolutionary diversification and size increase in freshwater habitats during the Early Permian, but subsequently declined during the middle and late Permian. Conodonts experienced their lowest diversity of their entire evolutionary history during the Permian. Permian chondrichthyan faunas are poorly known. Members of

2147-637: Is thrust along the Main Frontal Thrust over the Quaternary alluvium deposited by the rivers coming from the Himalaya ( Ganges , Indus , Brahmaputra and others), which demonstrates that the Himalaya is still a very active orogen . The Lesser Himalaya (LH) tectonic plate is mainly formed by Upper Proterozoic to lower Cambrian detrital sediments from the passive Indian margin intercalated with some granites and acid volcanics (1840 ±70 Ma). These sediments are thrust over

2260-645: The "North Himalayan Nappes" , have also been described within this unit. An almost complete stratigraphic record ranging from the Upper Proterozoic to the Eocene is preserved within the sediments of the TH. Stratigraphic analysis of these sediments yields important indications on the geological history of the northern continental margin of the Indian sub-continent from its Gondwanian evolution to its continental collision with Eurasia . The transition between

2373-582: The 1999 Chamoli Earthquake , all of which were recorded at magnitudes equal or greater than Mw 6.6. A recent study (Parija et al, 2021) sought to quantify the Coulomb Stress Transfer in the Western Himalayas. Coulomb stress transfer is used to quantify how earthquakes release stress, identifying areas that are put under increased stress and those that have been unloaded. This study and those like it are important in understanding

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2486-760: The Andes of South America, extends through the North American Cordillera , the Aleutian Range , on through Kamchatka Peninsula , Japan , Taiwan , the Philippines , Papua New Guinea , to New Zealand . The Andes is 7,000 kilometres (4,350 mi) long and is often considered the world's longest mountain system. The Alpide belt stretches 15,000 km across southern Eurasia , from Java in Maritime Southeast Asia to

2599-551: The Annamite Range . If the definition of a mountain range is stretched to include underwater mountains, then the Ocean Ridge forms the longest continuous mountain system on Earth, with a length of 65,000 kilometres (40,400 mi). The position of mountain ranges influences climate, such as rain or snow. When air masses move up and over mountains, the air cools, producing orographic precipitation (rain or snow). As

2712-914: The Capitanian Stage of the Permian was marked by the major Capitanian mass extinction event , associated with the eruption of the Emeishan Traps . The Permian (along with the Paleozoic) ended with the Permian–Triassic extinction event (colloquially known as the Great Dying), the largest mass extinction in Earth's history (which is the last of the three or four crises that occurred in the Permian), in which nearly 81% of marine species and 70% of terrestrial species died out, associated with

2825-723: The Central Himalaya . The change of the relative speed between the Indian and Asian plates from very fast (18-19.5 cm/yr) to fast (4.5 cm/yr) at about 55 Ma is circumstantial support for collision then. Since then there has been about 2500 km of crustal shortening and rotating of India by 45° counterclockwise in the Northwestern Himalaya to 10°-15° counterclockwise in North Central Nepal relative to Asia (Fig. 4). While most of

2938-668: The Cimmerian Superterranes , was part of Gondwana and was separated from Eurasia by the Paleo-Tethys Ocean (Fig. 1). During that period, the northern part of India was affected by a late phase of the Pan-African orogeny which is marked by an unconformity between Ordovician continental conglomerates and the underlying Cambrian marine sediments . Numerous granitic intrusions dated at around 500 Ma are also attributed to this event. In

3051-467: The Geological Society of London , after extensive Russian explorations undertaken with Édouard de Verneuil in the vicinity of the Ural Mountains in the years 1840 and 1841. Murchison identified "vast series of beds of marl , schist , limestone , sandstone and conglomerate" that succeeded Carboniferous strata in the region. Murchison, in collaboration with Russian geologists, named

3164-804: The Iberian Peninsula in Western Europe , including the ranges of the Himalayas , Karakoram , Hindu Kush , Alborz , Caucasus , and the Alps . The Himalayas contain the highest mountains in the world, including Mount Everest , which is 8,848 metres (29,029 ft) high. Mountain ranges outside these two systems include the Arctic Cordillera , Appalachians , Great Dividing Range , East Siberians , Altais , Scandinavians , Qinling , Western Ghats , Vindhyas , Byrrangas , and

3277-658: The Ladakh region, the "Tethys Himalaya synclinorium" passes gradually to the north in a large dome of greenschist to eclogitic metamorphic rocks. As with the HHCS, these metamorphic rocks represent the metamorphic equivalent of the sediments forming the base of the Tethys Himalaya. The " Precambrian Phe Formation" is also here intruded by several Ordovician (c. 480 Ma) granites. The Lamayuru and Markha Units are formed by flyschs and olistholiths deposited in

3390-613: The Mithrim Montes and Doom Mons on Titan, and Tenzing Montes and Hillary Montes on Pluto. Some terrestrial planets other than Earth also exhibit rocky mountain ranges, such as Maxwell Montes on Venus taller than any on Earth and Tartarus Montes on Mars . Jupiter's moon Io has mountain ranges formed from tectonic processes including the Boösaule , Dorian, Hi'iaka and Euboea Montes . Permian The Permian ( / ˈ p ɜːr m i . ə n / PUR -mee-ən )

3503-726: The North China Craton , the South China Block and Indochina fused to each other and Pangea by the end of the Permian. The Zechstein Sea , a hypersaline epicontinental sea , existed in what is now northwestern Europe. Large continental landmass interiors experience climates with extreme variations of heat and cold (" continental climate ") and monsoon conditions with highly seasonal rainfall patterns. Deserts seem to have been widespread on Pangaea. Such dry conditions favored gymnosperms , plants with seeds enclosed in

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3616-576: The Paleo-Tethys Ocean , a large ocean that existed between Asia and Gondwana. The Cimmeria continent rifted away from Gondwana and drifted north to Laurasia , causing the Paleo-Tethys Ocean to shrink. A new ocean was growing on its southern end, the Neotethys Ocean , an ocean that would dominate much of the Mesozoic Era. A magmatic arc, containing Hainan on its southwesternmost end, began to form as Panthalassa subducted under

3729-549: The Sydney Basin , and palaeoclimatic models of the Earth's climate based on the behaviour of modern weather patterns showing that such a megamonsoon would occur given the continental arrangement of the Permian. The aforementioned increasing equatorial aridity was likely driven by the development and intensification of this Pangaean megamonsoon. Permian marine deposits are rich in fossil mollusks , brachiopods , and echinoderms . Brachiopods were highly diverse during

3842-447: The U.S. states of Texas and New Mexico is so named because it has one of the thickest deposits of Permian rocks in the world. Sea levels dropped slightly during the earliest Permian (Asselian). The sea level was stable at several tens of metres above present during the Early Permian, but there was a sharp drop beginning during the Roadian, culminating in the lowest sea level of the entire Palaeozoic at around present sea level during

3955-647: The first appearance datum of specific species of conodont , an enigmatic group of jawless chordates with hard tooth-like oral elements. Conodonts are used as index fossils for most of the Palaeozoic and the Triassic. The Cisuralian Series is named after the strata exposed on the western slopes of the Ural Mountains in Russia and Kazakhstan. The name was proposed by J. B. Waterhouse in 1982 to comprise

4068-455: The highest relief (8848 m at Mt. Everest Chomolangma), among the highest erosion rates at 2–12 mm/yr, the source of some of the greatest rivers and the highest concentration of glaciers outside of the polar regions . This last feature earned the Himalaya its name, originating from the Sanskrit for "the abode of the snow". From south to north the Himalaya (Himalaya orogen)

4181-533: The metamorphic equivalents of the sedimentary series forming the base of the overlying " Tethys Himalaya " . The HHCS forms a major nappe which is thrust over the Lesser Himalaya along the " Main Central Thrust " (MCT). The Tethys Himalaya is an approximately 100-km-wide synclinorium formed by strongly folded and imbricated, weakly metamorphosed sedimentary series. Several nappes, termed

4294-463: The oceanic crust was "simply" subducted below the Tibetan block during the northward motion of India, at least three major mechanisms have been put forward, either separately or jointly, to explain what happened, since collision, to the 2500 km of "missing continental crust ". Even though it is more than reasonable to argue that this huge amount of crustal shortening most probably results from

4407-577: The pseudosuchians , dinosaurs , and pterosaurs in the following Triassic, first appeared and diversified during the Late Permian, including the first appearance of the Archosauriformes during the latest Permian. Cynodonts , the group of therapsids ancestral to modern mammals , first appeared and gained a worldwide distribution during the Late Permian. Another group of therapsids, the therocephalians (such as Lycosuchus ), arose in

4520-522: The region of Perm in Russia . The Permian witnessed the diversification of the two groups of amniotes , the synapsids and the sauropsids ( reptiles ). The world at the time was dominated by the supercontinent Pangaea , which had formed due to the collision of Euramerica and Gondwana during the Carboniferous. Pangaea was surrounded by the superocean Panthalassa . The Carboniferous rainforest collapse left behind vast regions of desert within

4633-808: The "Lesser Himalayan Sedimentary Zone (LHSZ) and the Lesser Himalayan Crystalline Nappes (LHCN)), Main Central thrust (MCT), Higher (or Greater) Himalayan crystallines (HHC), South Tibetan detachment system (STD), Tethys Himalaya (TH), and the Indus‐Tsangpo Suture Zone (ISZ). North of this lies the Transhimalaya in Tibet which is outside the Himalayas. The Himalayas border the Indo-Gangetic Plain to

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4746-435: The Asselian, Sakmarian, and Artinskian stages. The Kungurian was later added to conform to the Russian "Lower Permian". Albert Auguste Cochon de Lapparent in 1900 had proposed the "Uralian Series", but the subsequent inconsistent usage of this term meant that it was later abandoned. The Asselian was named by the Russian stratigrapher V.E. Ruzhenchev in 1954, after the Assel River in the southern Ural Mountains. The GSSP for

4859-438: The Cisuralian, Guadalupian, and Lopingian. Geologists divide the rocks of the Permian into a stratigraphic set of smaller units called stages , each formed during corresponding time intervals called ages. Stages can be defined globally or regionally. For global stratigraphic correlation, the International Commission on Stratigraphy (ICS) ratify global stages based on a Global Boundary Stratotype Section and Point (GSSP) from

4972-428: The Cisuralian. Another cool period began around the middle Capitanian. This cool period, lasting for 3-4 Myr, was known as the Kamura Event. It was interrupted by the Emeishan Thermal Excursion in the late part of the Capitanian, around 260 million years ago, corresponding to the eruption of the Emeishan Traps . This interval of rapid climate change was responsible for the Capitanian mass extinction event. During

5085-450: The Cisuralian. Permian synapsids included some large members such as Dimetrodon . The special adaptations of synapsids enabled them to flourish in the drier climate of the Permian and they grew to dominate the vertebrates. A faunal turnover occurred around the transition between the Cisuralian and Guadalupian, with the decline of amphibians and the replacement of pelycosaurs (a paraphyletic group) with more advanced therapsids , although

5198-424: The Early Carboniferous , an early stage of rifting developed between the Indian subcontinent and the Cimmerian Superterranes. During the Early Permian , this rift developed into the Neotethys ocean (Fig. 2). From that time on, the Cimmerian Superterranes drifted away from Gondwana towards the north. Nowadays, Iran , Afghanistan and Tibet are partly made up of these terranes. In the Norian (210 Ma),

5311-425: The Early Permian Chemnitz petrified forest of Germany demonstrates that they had complex branching patterns similar to modern angiosperm trees. By the Late Permian, high thin forests had become widespread across the globe, as evidenced by the global distribution of weigeltisaurids. The oldest likely record of Ginkgoales (the group containing Ginkgo and its close relatives) is Trichopitys heteromorpha from

5424-504: The Early Triassic, but a Permian origin is suspected. The diversity of coelacanths is relatively low throughout the Permian in comparison to other marine fishes, though there is an increase in diversity during the terminal Permian (Changhsingian), corresponding with the highest diversity in their evolutionary history during the Early Triassic. Diversity of freshwater fish faunas was generally low and dominated by lungfish and "Paleopterygians". The last common ancestor of all living lungfish

5537-459: The Eurasian plate results in mega earthquakes. These seismic events can reach greater than MW 8 and result in intense damage to infrastructure. The mid-crustal ramp in the Himalayas is a key geologic feature in the history for both long-term and short-term seismic processes linked to deformation and shortening. Over the last 15 Ma, the ramp has gradually moved south due to duplexing, accretion, and tectonic undercutting. The ongoing active collision of

5650-415: The HHCS are of late Proterozoic to early Cambrian age, much younger metasediments can also be found in several areas, e.g. Mesozoic in the Tandi syncline of Nepal and Warwan Valley of Kistwar in Kashmir , Permian in the "Tschuldo slice" , Ordovician to Carboniferous in the " Sarchu area" on Leh-Manali Highway . It is now generally accepted that the metasediments of the HHCS represent

5763-419: The Indian and Eurasian continental plates challenges one hypothesis for plate motion which relies on subduction. One of the most striking aspects of the Himalayan orogen is the lateral continuity of its major tectonic elements. The Himalaya is classically divided into four tectonic units that can be followed for more than 2400 km along the belt (Fig. 5 and Fig. 7). The Sub-Himalayan tectonic plate

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5876-472: The Late Permian. Members of the modern orders Archostemata and Adephaga are known from the Late Permian. Complex wood boring traces found in the Late Permian of China suggest that members of Polyphaga , the most diverse group of modern beetles, were also present by the Late Permian. The terrestrial fossil record of the Permian is patchy and temporally discontinuous. Early Permian records are dominated by equatorial Europe and North America, while those of

5989-501: The Late Permian. By the Changhsingian, only a handful (4-6) genera remained. Corals exhibited a decline in diversity over the course of the Middle and Late Permian. Terrestrial life in the Permian included diverse plants, fungi , arthropods , and various types of tetrapods . The period saw a massive desert covering the interior of Pangaea . The warm zone spread in the northern hemisphere, where extensive dry desert appeared. The rocks formed at that time were stained red by iron oxides,

6102-514: The Lopingian in China. Modern amphibians ( lissamphibians ) are suggested to have originated during Permian, descending from a lineage of dissorophoid temnospondyls or lepospondyls . The diversity of fish during the Permian is relatively low compared to the following Triassic. The dominant group of bony fishes during the Permian were the " Paleopterygii " a paraphyletic grouping of Actinopterygii that lie outside of Neopterygii . The earliest unequivocal members of Neopterygii appear during

6215-418: The Lopingian series. The GSSP for the base of the Wuchiapingian is located at Penglaitan, Guangxi , China and was ratified in 2004. The boundary is defined by the first appearance of Clarkina postbitteri postbitteri The Changhsingian was originally derived from the Changxing Limestone, a geological unit first named by the Grabau in 1923, ultimately deriving from Changxing County , Zhejiang .The GSSP for

6328-408: The Lopingian to a series, including all Permian deposits in South China that overlie the Maokou Limestone. In 1995, a vote by the Subcommission on Permian Stratigraphy of the ICS adopted the Lopingian as an international standard chronostratigraphic unit. The Wuchiapinginan and Changhsingian were first introduced in 1962, by J. Z. Sheng as the "Wuchiaping Formation" and "Changhsing Formation" within

6441-450: The Middle Permian. There were no flying vertebrates, though the extinct lizard-like reptile family Weigeltisauridae from the Late Permian had extendable wings like modern gliding lizards , and are the oldest known gliding vertebrates. Permian stem-amniotes consisted of lepospondyli and batrachosaurs , according to some phylogenies; according to others, stem-amniotes are represented only by diadectomorphs . Temnospondyls reached

6554-547: The Middle and Late Permian are dominated by temperate Karoo Supergroup sediments of South Africa and the Ural region of European Russia. Early Permian terrestrial faunas of North America and Europe were dominated by primitive pelycosaur synapsids including the herbivorous edaphosaurids , and carnivorous sphenacodontids , diadectids and amphibians . Early Permian reptiles, such as acleistorhinids , were mostly small insectivores. Synapsids (the group that would later include mammals) thrived and diversified greatly during

6667-410: The Ochoan, corresponding to the Lopingian. During the Permian, all the Earth 's major landmasses were collected into a single supercontinent known as Pangaea , with the microcontinental terranes of Cathaysia to the east. Pangaea straddled the equator and extended toward the poles, with a corresponding effect on ocean currents in the single great ocean (" Panthalassa ", the "universal sea"), and

6780-582: The Permian, representing up to a third of all insects at some localities. Mecoptera (sometimes known as scorpionflies) first appeared during the Early Permian, going on to become diverse during the Late Permian. Some Permian mecopterans, like Mesopsychidae have long proboscis that suggest they may have pollinated gymnosperms. The earliest known beetles appeared at the beginning of the Permian. Early beetles such as members of Permocupedidae were likely xylophagous , feeding on decaying wood. Several lineages such as Schizophoridae expanded into aquatic habitats by

6893-473: The Permian-Triassic boundary, corresponding to the eruption of the Siberian Traps , which released more than 5 teratonnes of CO 2 , more than doubling the atmospheric carbon dioxide concentration. A -2% δ O excursion signifies the extreme magnitude of this climatic shift. This extremely rapid interval of greenhouse gas release caused the Permian-Triassic mass extinction, as well as ushering in an extreme hothouse that persisted for several million years into

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7006-454: The Permian. Xenacanthiformes , another extinct group of shark-like chondrichthyans, were common in freshwater habitats, and represented the apex predators of freshwater ecosystems. Four floristic provinces in the Permian are recognised, the Angaran , Euramerican, Gondwanan, and Cathaysian realms. The Carboniferous Rainforest Collapse would result in the replacement of lycopsid -dominated forests with tree-fern dominated ones during

7119-456: The Permian. The extinct order Productida was the predominant group of Permian brachiopods, accounting for up to about half of all Permian brachiopod genera. Brachiopods also served as important ecosystem engineers in Permian reef complexes. Amongst ammonoids , Goniatitida were a major group during the Early-Mid Permian, but declined during the Late Permian. Members of the order Prolecanitida were less diverse. The Ceratitida originated from

7232-515: The Permian. This is likely due to competition by Hemiptera , due to their similar mouthparts and therefore ecology. Primitive relatives of damselflies and dragonflies ( Meganisoptera ), which include the largest flying insects of all time, also declined during the Permian. Holometabola , the largest group of modern insects, also diversified during this time. " Grylloblattidans ", an extinct group of winged insects thought to be related to modern ice crawlers , reached their apex of diversity during

7345-449: The Sub-himalayan range along the Main Boundary Thrust (MBT). The Lesser Himalaya often appears in tectonic windows (Kishtwar or Larji-Kulu-Rampur windows) within the High Himalaya Crystalline Sequence. The Central Himalayan Domain forms the backbone of the Himalayan orogen and encompasses the areas with the highest topographic relief (highest peaks). It is commonly separated into four zones. Approximately 30 different names exist in

7458-475: The Usolka section in the southern Urals, which was ratified in 2018. The GSSP is defined by the first appearance of Sweetognathus binodosus . The Artinskian was named after the city of Arti in Sverdlovsk Oblast , Russia. It was named by Karpinsky in 1874. The Artinskian currently lacks a defined GSSP. The proposed definition for the base of the Artinskian is the first appearance of Sweetognathus aff. S. whitei. The Kungurian takes its name after Kungur ,

7571-401: The Word Formation by Johan August Udden in 1916, Glenister and Furnish in 1961 was the first publication to use it as a chronostratigraphic term as a substage of the Guadalupian Stage. The GSSP for the base of the Wordian is located in Guadalupe Pass, Texas, within the sediments of the Getaway Limestone Member of the Cherry Canyon Formation , which was ratified in 2001. The base of the Wordian

7684-413: The Wuchiapingian, followed by a slight rise during the Changhsingian. The Permian was cool in comparison to most other geologic time periods, with modest pole to Equator temperature gradients. At the start of the Permian, the Earth was still in the Late Paleozoic icehouse (LPIA), which began in the latest Devonian and spanned the entire Carboniferous period, with its most intense phase occurring during

7797-575: The air descends on the leeward side, it warms again (following the adiabatic lapse rate ) and is drier, having been stripped of much of its moisture. Often, a rain shadow will affect the leeward side of a range. As a consequence, large mountain ranges, such as the Andes, compartmentalize continents into distinct climate regions . Mountain ranges are constantly subjected to erosional forces which work to tear them down. The basins adjacent to an eroding mountain range are then filled with sediments that are buried and turned into sedimentary rock . Erosion

7910-506: The amount of lava estimated to have been produced during this period, the worst-case scenario is the release of enough carbon dioxide from the eruptions to raise world temperatures five degrees Celsius. Another hypothesis involves ocean venting of hydrogen sulfide gas. Portions of the deep ocean will periodically lose all of its dissolved oxygen allowing bacteria that live without oxygen to flourish and produce hydrogen sulfide gas. If enough hydrogen sulfide accumulates in an anoxic zone ,

8023-411: The ancestors of many present-day families. Rich forests were present in many areas, with a diverse mix of plant groups. The southern continent saw extensive seed fern forests of the Glossopteris flora. Oxygen levels were probably high there. The ginkgos and cycads also appeared during this period. Insects, which had first appeared and become abundant during the preceding Carboniferous, experienced

8136-647: The base of the Asselian is located in the Aidaralash River valley near Aqtöbe , Kazakhstan, which was ratified in 1996. The beginning of the stage is defined by the first appearance of Streptognathodus postfusus . The Sakmarian is named in reference to the Sakmara River in the southern Urals, and was coined by Alexander Karpinsky in 1874. The GSSP for the base of the Sakmarian is located at

8249-477: The base of the Capitanian is located at Nipple Hill in the southeast Guadalupe Mountains of Texas, and was ratified in 2001, the beginning of the stage is defined by the first appearance of Jinogondolella postserrata. The Lopingian was first introduced by Amadeus William Grabau in 1923 as the "Loping Series" after Leping , Jiangxi , China. Originally used as a lithostraphic unit, T.K. Huang in 1932 raised

8362-593: The base of the Changhsingian is located 88 cm above the base of the Changxing Limestone in the Meishan D section, Zhejiang, China and was ratified in 2005, the boundary is defined by the first appearance of Clarkina wangi. The GSSP for the base of the Triassic is located at the base of Bed 27c at the Meishan D section, and was ratified in 2001. The GSSP is defined by the first appearance of

8475-502: The chondrichthyan clade Holocephali , which contains living chimaeras , reached their apex of diversity during the Carboniferous-Permian, the most famous Permian representative being the "buzz-saw shark" Helicoprion , known for its unusual spiral shaped spiral tooth whorl in the lower jaw. Hybodonts , a group of shark-like chondrichthyans, were widespread and abundant members of marine and freshwater faunas throughout

8588-636: The climate became notably more arid at the end of the Carboniferous and beginning of the Permian. Nonetheless, temperatures continued to cool during most of the Asselian and Sakmarian, during which the LPIA peaked. By 287 million years ago, temperatures warmed and the South Pole ice cap retreated in what was known as the Artinskian Warming Event (AWE), though glaciers remained present in the uplands of eastern Australia, and perhaps also

8701-536: The collision of the continental crust of two tectonic plates , namely, the Indian Plate thrusting into the Eurasian Plate . The Himalaya-Tibet region supplies fresh water for more than one-fifth of the world population , and accounts for a quarter of the global sedimentary budget . Topographically, the belt has many superlatives : the highest rate of uplift (nearly 10 mm/year at Nanga Parbat),

8814-801: The conodont Hindeodus parvus . The Russian Tatarian Stage includes the Lopingian, Capitanian and part of the Wordian, while the underlying Kazanian includes the rest of the Wordian as well as the Roadian. In North America, the Permian is divided into the Wolfcampian (which includes the Nealian and the Lenoxian stages); the Leonardian (Hessian and Cathedralian stages); the Guadalupian; and

8927-552: The continental interior by the more advanced seed ferns and early conifers as a result of the Carboniferous rainforest collapse . At the close of the Permian, lycopod and equisete swamps reminiscent of Carboniferous flora survived only in Cathaysia , a series of equatorial islands in the Paleo-Tethys Ocean that later would become South China . The Permian saw the radiation of many important conifer groups, including

9040-449: The continental interior. Amniotes, which could better cope with these drier conditions, rose to dominance in place of their amphibian ancestors. Various authors recognise at least three, and possibly four extinction events in the Permian. The end of the Early Permian ( Cisuralian ) saw a major faunal turnover, with most lineages of primitive " pelycosaur " synapsids becoming extinct, being replaced by more advanced therapsids . The end of

9153-402: The current state of fault zones in the region, as well as their potential for rupture in the future. Localized geology and geomorphology topics for various parts of the Himalaya are discussed on other pages: Mountain range Mountain ranges are usually segmented by highlands or mountain passes and valleys . Individual mountains within the same mountain range do not necessarily have

9266-633: The decline of early synapsid clades was apparently a slow event that lasted about 20 Ma, from the Sakmarian to the end of the Kungurian . Predator-prey interactions among terrestrial synapsids became more dynamic. If terrestrial deposition ended around the end of the Cisuralian in North America and began in Russia during the early Guadalupian, a continuous record of the transition is not preserved. Uncertain dating has led to suggestions that there

9379-534: The diverse Dinocephalia . Dinocephalians become extinct at the end of the Middle Permian, during the Capitanian mass extinction event . Late Permian faunas are dominated by advanced therapsids such as the predatory sabertoothed gorgonopsians and herbivorous beaked dicynodonts , alongside large herbivorous pareiasaur parareptiles . The Archosauromorpha , the group of reptiles that would give rise to

9492-465: The earliest Permian of France. The oldest known fossils definitively assignable to modern cycads are known from the Late Permian. In Cathaysia, where a wet tropical frost-free climate prevailed, the Noeggerathiales , an extinct group of tree fern-like progymnosperms were a common component of the flora The earliest Permian (~ 298 million years ago) Cathyasian Wuda Tuff flora, representing

9605-653: The early Wuchiapingian, following the emplacement of the Emeishan Traps, global temperatures declined as carbon dioxide was weathered out of the atmosphere by the large igneous province's emplaced basalts. The late Wuchiapingian saw the finale of the Late Palaeozoic Ice Age, when the last Australian glaciers melted. The end of the Permian is marked by a temperature excursion, much larger than the Emeishan Thermal Excursion, at

9718-485: The east. This mass of rock was removed as the range was actively undergoing uplift. The removal of such a mass from the core of the range most likely caused further uplift as the region adjusted isostatically in response to the removed weight. Rivers are traditionally believed to be the principal cause of mountain range erosion, by cutting into bedrock and transporting sediment. Computer simulation has shown that as mountain belts change from tectonically active to inactive,

9831-494: The end of the Permian. Nautiloids , a subclass of cephalopods, surprisingly survived this occurrence. There is evidence that magma , in the form of flood basalt , poured onto the Earth's surface in what is now called the Siberian Traps , for thousands of years, contributing to the environmental stress that led to mass extinction. The reduced coastal habitat and highly increased aridity probably also contributed. Based on

9944-704: The eruption of the Siberian Traps . It took well into the Triassic for life to recover from this catastrophe; on land, ecosystems took 30 million years to recover. Prior to the introduction of the term Permian , rocks of equivalent age in Germany had been named the Rotliegend and Zechstein , and in Great Britain as the New Red Sandstone . The term Permian was introduced into geology in 1841 by Sir Roderick Impey Murchison , president of

10057-580: The family Daraelitidae within Prolecanitida during the mid-Permian, and extensively diversified during the Late Permian. Only three families of trilobite are known from the Permian, Proetidae , Brachymetopidae and Phillipsiidae . Diversity, origination and extinction rates during the Early Permian were low. Trilobites underwent a diversification during the Kungurian-Wordian, the last in their evolutionary history, before declining during

10170-429: The gas can rise into the atmosphere. Oxidizing gases in the atmosphere would destroy the toxic gas, but the hydrogen sulfide would soon consume all of the atmospheric gas available. Hydrogen sulfide levels might have increased dramatically over a few hundred years. Models of such an event indicate that the gas would destroy ozone in the upper atmosphere allowing ultraviolet radiation to kill off species that had survived

10283-562: The generally low-grade sediments of the "Tethys Himalaya" and the underlying low- to high-grade rocks of the "High Himalayan Crystalline Sequence" is usually progressive. But in many places along the Himalayan belt, this transition zone is marked by a major structure, the "Central Himalayan Detachment System" , also known as the " South Tibetan Detachment System " or "North Himalayan Normal Fault" , which has indicators of both extension and compression. See ongoing geologic studies section below. "Nyimaling- Tso Morari Metamorphic Dome" in

10396-748: The late Carboniferous in Euramerica, and result in the differentiation of the Cathaysian floras from those of Euramerica. The Gondwanan floristic region was dominated by Glossopteridales , a group of woody gymnosperm plants, for most of the Permian, extending to high southern latitudes. The ecology of the most prominent glossopterid, Glossopteris , has been compared to that of bald cypress , living in mires with waterlogged soils. The tree-like calamites , distant relatives of modern horsetails , lived in coal swamps and grew in bamboo -like vertical thickets. A mostly complete specimen of Arthropitys from

10509-540: The latter part of the Pennsylvanian epoch. A significant trend of increasing aridification can be observed over the course of the Cisuralian. Early Permian aridification was most notable in Pangaean localities at near-equatorial latitudes. Sea levels also rose notably in the Early Permian as the LPIA slowly waned. At the Carboniferous-Permian boundary, a warming event occurred. In addition to becoming warmer,

10622-422: The literature to describe this unit; the most frequently found equivalents are "Greater Himalayan Sequence" , " Tibetan Slab " and "High Himalayan Crystalline" . It is a 30-km-thick, medium- to high-grade metamorphic sequence of metasedimentary rocks which are intruded in many places by granites of Ordovician (c. 500 Ma) and early Miocene (c. 22 Ma) age. Although most of the metasediments forming

10735-432: The lower plate tore off into the mantle leading to high amounts of rebound. The second model states that the rocks got to a certain point in subduction and then were forced back up through the channel they came down due to a space problem. The third model states that the thick continental crust of India further exacerbated the space problem and caused the corner flow of those rocks back up the channel. The fourth model includes

10848-510: The mechanism of emplacing higher grade metamorphic rocks on top of lower grade metamorphic rocks still strongly debated, Kohn believes that it is due to long periods of transportation of higher grade metamorphic rocks on the Main Himalayan Thrust. Essentially, the longer the higher grade rocks were spatially interacting with the thrust, the farther they were transported. The exhumation of eclogite and granulite rocks can be explained by several different models. The first model includes slab tear where

10961-514: The most extensive extinction event recorded in paleontology : the Permian–Triassic extinction event . 90 to 95% of marine species became extinct , as well as 70% of all land organisms. It is also the only known mass extinction of insects. Recovery from the Permian–Triassic extinction event was protracted; on land, ecosystems took 30 million years to recover. Trilobites , which had thrived since Cambrian times, finally became extinct before

11074-473: The most potent greenhouse gases ) into the atmosphere to raise world temperatures an additional five degrees Celsius. The frozen methane hypothesis helps explain the increase in carbon-12 levels found midway in the Permian–Triassic boundary layer. It also helps explain why the first phase of the layer's extinctions was land-based, the second was marine-based (and starting right after the increase in C-12 levels), and

11187-414: The mountainous regions of far northern Siberia. Southern Africa also retained glaciers during the late Cisuralian in upland environments. The AWE also witnessed aridification of a particularly great magnitude. In the late Kungurian, cooling resumed, resulting in a cool glacial interval that lasted into the early Capitanian, though average temperatures were still much higher than during the beginning of

11300-561: The name Dyassic , from Dyas and Trias , though Murchison rejected this in 1871. The Permian system was controversial for over a century after its original naming, with the United States Geological Survey until 1941 considering the Permian a subsystem of the Carboniferous equivalent to the Mississippian and Pennsylvanian . The Permian Period is divided into three epochs , from oldest to youngest,

11413-713: The next geologic epoch, the Triassic. The Permian climate was also extremely seasonal and characterised by megamonsoons , which produced high aridity and extreme seasonality in Pangaea's interiors. Precipitation along the western margins of the Palaeo-Tethys Ocean was very high. Evidence for the megamonsoon includes the presence of megamonsoonal rainforests in the Qiangtang Basin of Tibet, enormous seasonal variation in sedimentation, bioturbation, and ichnofossil deposition recorded in sedimentary facies in

11526-498: The opening of the "South Indian Ocean" (Fig. 3). In the Late Cretaceous (84 Ma), the Indian plate began its very rapid northward drift covering a distance of about 6000 km, with the oceanic-oceanic subduction continuing until the final closure of the oceanic basin and the obduction of oceanic ophiolite onto India and the beginning of continent-continent tectonic interaction starting at about 65  Ma in

11639-585: The period after the surrounding Russian region of Perm, which takes its name from the medieval kingdom of Permia that occupied the same area hundreds of years prior, and which is now located in the Perm Krai administrative region. Between 1853 and 1867, Jules Marcou recognised Permian strata in a large area of North America from the Mississippi River to the Colorado River and proposed

11752-627: The rate of erosion drops because there are fewer abrasive particles in the water and fewer landslides. Mountains on other planets and natural satellites of the Solar System, including the Moon , are often isolated and formed mainly by processes such as impacts, though there are examples of mountain ranges (or "Montes") somewhat similar to those on Earth. Saturn 's moon Titan and Pluto , in particular, exhibit large mountain ranges in chains composed mainly of ices rather than rock. Examples include

11865-419: The rest of the Late Permian, and should be regarded as a separate epoch. The tripartite split was adopted after a formal proposal by Glenister et al. (1999). Historically, most marine biostratigraphy of the Permian was based on ammonoids ; however, ammonoid localities are rare in Permian stratigraphic sections, and species characterise relatively long periods of time. All GSSPs for the Permian are based around

11978-439: The result of intense heating by the sun of a surface devoid of vegetation cover. A number of older types of plants and animals died out or became marginal elements. The Permian began with the Carboniferous flora still flourishing. About the middle of the Permian a major transition in vegetation began. The swamp -loving lycopod trees of the Carboniferous, such as Lepidodendron and Sigillaria , were progressively replaced in

12091-488: The rocks being transported along the Main Himalayan Thrust. ISZ, also called Indus-Yarlung suture zone , Yarlung-Zangpo Suture Zone or Yarlung-Tsangpo Suture Zone, defines the zone of collision between the Indian Plate and the Ladakh Batholith (also Transhimalaya or Karakoram-Lhasa Block ) to the north. This suture zone is formed by: The modern day rate of convergence between the Indian and Eurasian plates

12204-536: The same geologic structure or petrology . They may be a mix of different orogenic expressions and terranes , for example thrust sheets , uplifted blocks , fold mountains, and volcanic landforms resulting in a variety of rock types . Most geologically young mountain ranges on the Earth's land surface are associated with either the Pacific Ring of Fire or the Alpide belt . The Pacific Ring of Fire includes

12317-650: The south, Pamir Mountains to the west in Central Asia , and the Hengduan Mountains to the east on the China–Myanmar border . From east to west the Himalayas are divided into 3 regions, Eastern Himalaya , Central Himalaya, and Western Himalaya, which collectively house several nations and states . During Late Precambrian and the Palaeozoic , the Indian subcontinent , bounded to the north by

12430-408: The southeastern South China. The Central Pangean Mountains , which began forming due to the collision of Laurasia and Gondwana during the Carboniferous, reached their maximum height during the early Permian around 295 million years ago, comparable to the present Himalayas , but became heavily eroded as the Permian progressed. The Kazakhstania block collided with Baltica during the Cisuralian, while

12543-584: The spread of conifers and their increasing prevalence throughout terrestrial ecosystems. Bennettitales , which would go on to become in widespread the Mesozoic, first appeared during the Cisuralian in China. Lyginopterids , which had declined in the late Pennsylvanian and subsequently have a patchy fossil record, survived into the Late Permian in Cathaysia and equatorial east Gondwana. The Permian ended with

12656-413: The toxic gas. There are species that can metabolize hydrogen sulfide. Another hypothesis builds on the flood basalt eruption theory. An increase in temperature of five degrees Celsius would not be enough to explain the death of 95% of life. But such warming could slowly raise ocean temperatures until frozen methane reservoirs below the ocean floor near coastlines melted, expelling enough methane (among

12769-667: Was named in 1968 in reference to the Road Canyon Member of the Word Formation in Texas. The GSSP for the base of the Roadian is located 42.7m above the base of the Cutoff Formation in Stratotype Canyon, Guadalupe Mountains, Texas, and was ratified in 2001. The beginning of the stage is defined by the first appearance of Jinogondolella nankingensis . The Wordian was named in reference to

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