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107-736: The Fremouw Formation is mostly Triassic in age, with the oldest rocks dating back to the latest Permian . Much of the formation is quartzose sandstone that was deposited in stream beds. It overlies the Permian Buckley Formation , which consists of coal and Glossopteris fossils. The formation is informally divided into lower, middle, and upper units. Most fossils are found in the Lower Fremouw Formation. Here, bones are preserved in fine-grained siltstones and mudstones , coarse-grained channel sandstones, and conglomerates . Well-preserved plants are common in

214-630: 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

321-685: 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

428-463: A combination of material from brachyopid temnospondyls, a dicynodont , and other animals A. polyodon Upper Fremouw A mostly complete skull A capitosaur temnospondyl C. kitchingi Lower Fremouw A partial skull and other bone fragments A lydekkerinid temnospondyl [REDACTED] K. collinsoni Upper Fremouw Large snout fragment A stereospondyl temnospondyl [REDACTED] P. sp. Upper Fremouw Fragment of

535-604: 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

642-527: A large icefalls at the escarpment west of Mount Rosenwald and entering Shackleton Glacier south of Mount Heekin . Discovered and photographed by United States Navy Operation Highjump (OpHjp) (1946–47) on the flights of Feb. 16, 1947. Named by US-ACAN for Sgt. George E. Baldwin, United States Marine Corps (USMC), photographer on Flight 8A. 84°57′S 177°30′W  /  84.950°S 177.500°W  / -84.950; -177.500 . A glacier, 10 nautical miles (19 km; 12 mi) long, draining

749-540: 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

856-525: 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

963-588: 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

1070-689: 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

1177-642: 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

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1284-663: 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

1391-452: 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

1498-914: 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

1605-649: The Cumulus Hills and Red Raider Rampart to enter the south side of McGregor Glacier. Named by US-ACAN for Harold C. Gatlin, USARP meteorologist at the South Pole Station, winter 1964. 85°01′S 175°00′W  /  85.017°S 175.000°W  / -85.017; -175.000 . A tributary glacier about 8 nautical miles (15 km; 9.2 mi) long, flowing west from the north side of Mount Finley to enter Shackleton Glacier just north of Lockhart Ridge . Named by F. Alton Wade, leader of

1712-467: 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

1819-726: 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

1926-644: 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

2033-822: The Permo-Triassic boundary , which marks the Permo-Triassic mass extinction. Around the world, the fossil record of many tetrapod groups is absent or very limited in Early Triassic rocks, implying a major decline in diversity after the extinction. The presence of many of these groups in Middle Triassic strata indicates that long ghost lineages must have extended back into the Early Triassic. Tetrapods such as temnospondyl amphibians, diapsid reptiles, and dicynodont therapsids were common in

2140-775: The Queen Maud Mountains to enter the Ross Ice Shelf between Mount Speed and Waldron Spurs. Discovered by the United States Antarctic Service (USAS) (1939–41) and named by the Advisory Committee on Antarctic Names (US-ACAN) for Sir Ernest Shackleton , British Antarctic explorer. The Shackleton Glacier originates in the East Antarctic Ice Sheet and flows northeast between Dismal Buttress to

2247-549: 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

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2354-447: 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

2461-647: 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

2568-577: 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

2675-522: 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

2782-605: 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

2889-514: 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

2996-628: 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

3103-450: 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

3210-859: The Cumulus Hills to enter Shackleton Glacier just northeast of Vickers Nunatak. Named by the Southern Party of the New Zealand Geological Survey Antarctic Expedition (NZGSAE) (1961–62) for W.R. Logie, New Zealand maintenance officer and field mechanic who spent nearly two years in the Antarctic and was Deputy-Leader of Scott Base during the 1962–63 season. 85°14′S 175°38′W  /  85.233°S 175.633°W  / -85.233; -175.633 . A narrow steep-walled glacier 2 nautical miles (3.7 km; 2.3 mi) long, descending

3317-500: 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

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3424-504: 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

3531-564: The Fremouw Formation. Logs have been found in channel deposits, and roots and stems have been found in permineralized soil. Smaller fossils on Fremouw Peak include cycads , horsetails , seed ferns , Osmundaceae ferns, and even fungi . One cycad called Antarcticycas is similar in appearance to the living Bowenia of Australia . In 2003, 99 fossilized tree trunks were described from Gordon Valley. These trunks comprise an intact fossilized forest, allowing for an estimation of

3638-780: The Gemini nunataks the Gerasimou Glacier and Forman Glacier enter from the west before the mouth of the Shackleton Glacier. From the right (east) the Shackleton Glacier is fed by the Dick Glacier and McCuistion Glacier. It is joined by the Massam Glacier at its mouth. The Barrett Glacier enters the Ross Ice Shelf just east of the Shackleton Glacier. Download coordinates as: Tributaries from

3745-510: The Late Permian and seemed to have recovered by the Middle Triassic, but there is little record of their presence in the Early Triassic. All of these tetrapods are present in Early Triassic strata of the Fremouw Formation, suggesting that Antarctica served as a refugium for these animals. During the extinction, global temperatures rose and the supercontinent Pangea moved northward, putting pressure on populations that could not adapt to

3852-472: 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

3959-617: 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,

4066-623: 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

4173-605: 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

4280-598: 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

4387-514: 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

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4494-598: 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

4601-710: The NZGSAE (1961–62) for E. Vickers, radio operator at Scott Base, who was in contact with the Southern Party almost every day during the three months they were in the field. 85°07′S 175°51′W  /  85.117°S 175.850°W  / -85.117; -175.850 . A small, isolated nunatak lying 5 nautical miles (9.3 km; 5.8 mi) northeast of Matador Mountain , in the east part of Shackleton Glacier. Named by US-ACAN for Henry J. Eckins, USARP meteorologist at South Pole Station, winter 1961. 84°54′S 176°00′W  /  84.900°S 176.000°W  / -84.900; -176.000 . A large nunatak at

4708-514: 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

4815-582: 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

4922-603: 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

5029-508: 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

5136-524: 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

5243-515: 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

5350-432: The Queen Maud Mountains. Named by US-ACAN after John H. Forman, Construction Mechanic, USN, a member of the McMurdo Station winter party, 1959. Tributaries from the right (east) of the glacier are: 85°26′S 176°25′W  /  85.433°S 176.417°W  / -85.433; -176.417 . A broad tributary glacier, flowing from the polar plateau northwest between Roberts Massif and Cumulus Hills to enter

5457-476: The Queen Maud Mountains. Named by US-ACAN for Lt. Alan L. Dick, a member of U.S. Navy Squadron VX-6 during Deep Freeze 1964. 84°49′S 175°30′W  /  84.817°S 175.500°W  / -84.817; -175.500 . A tributary glacier, 4 nautical miles (7.4 km; 4.6 mi) long, which flows west along the north side of Lubbock Ridge to enter Shackleton Glacier. Named by US-ACAN for Joshua P. McCuistion, Construction Driver 1st Class, USN, who

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5564-451: The Shackleton Glacier. It trends northward from Matador Mountain . Named by the Southern Party of the NZGSAE (1961–62) for Charles W. Swithinbank, a member of the University of Michigan glaciological and survey parties to the major glaciers feeding the Ross Ice Shelf in 1960-61 and 1961-62. 84°42′S 176°38′W  /  84.700°S 176.633°W  / -84.700; -176.633 . Two nunataks of similar size and appearance in

5671-399: The Southern Party of NZGSAE (1963–64) for D. Massam, a member of that party. 84°37′S 174°10′W  /  84.617°S 174.167°W  / -84.617; -174.167 . A glacier draining from the north slopes of the Prince Olav Mountains , about 15 nautical miles (28 km; 17 mi) long, flowing between Longhorn Spurs and Gabbro Hills to the Ross Ice Shelf. Named by

5778-411: The Southern Party of NZGSAE (1963–64) for Peter J. Barrett, geologist with that party. Features in the glacier, from south to north, include: 85°20′S 176°40′W  /  85.333°S 176.667°W  / -85.333; -176.667 . A massive nunatak in the upper Shackleton Glacier, about 11 nautical miles (20 km; 13 mi) southeast of Mount Black. Named by the Southern Party of

5885-443: The Texas Tech Shackleton Glacier Expeditions (1962-63 and 1964–65), for Vestal L. Yeats, a member of the Texas Technological College faculty and of both expeditions. 84°53′S 175°50′W  /  84.883°S 175.833°W  / -84.883; -175.833 . A tributary glacier, 7 nautical miles (13 km; 8.1 mi) long, flowing west from Mount Campbell to enter Shackleton Glacier just north of Taylor Nunatak , in

5992-475: 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 ,

6099-401: 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

6206-413: 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

6313-506: 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 ,

6420-411: 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

6527-467: The area around the Beardmore Glacier to uncover more fossils. Since then, fragmentary remains of temnospondyls, therapsids , and archosauriform reptiles have all been found in the formation. These fossils are found around the Shackleton and Beardmore glaciers, in places such as Gordon Valley and Fremouw Peak . Austrobrachyops A. jenseni Lower Fremouw Jaw fragment, pterygoid bone , and other small fragments A nomen dubium based on

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6634-405: 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

6741-418: 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

6848-404: 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

6955-429: 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

7062-449: 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

7169-399: 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

7276-434: 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

7383-449: 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

7490-458: 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

7597-457: The distribution of plants and tree cover. Dicroidium fossils are present around the conifer-like stumps, suggesting that they were the leaves of these large trees. Based on the geology of the area, the trees grew alongside riverbanks and on floodplains. The structure of the plants shows no adaptation towards cold tolerance, suggesting that the climate was much warmer in the Triassic. The Fremouw Formation preserves many tetrapod fossils that span

7704-470: 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

7811-465: 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

7918-573: 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

8025-620: The east side of Shackleton Glacier, just south of the terminus of Dick Glacier, in the Queen Maud Mountains. Named by the Southern Party of NZGSAE (1961–62) for Thomas F. Taylor, topographic surveyor, USGS, who worked near the mouth of Shackleton Glacier in the summers of 1960-61 and 1961–62, and in the Pensacola Mountains, 1962–63. 85°00′S 177°05′W  /  85.000°S 177.083°W  / -85.000; -177.083 . A spectacular medial moraine in

8132-431: 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

8239-704: 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

8346-580: 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

8453-429: 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

8560-748: 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

8667-664: 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,

8774-644: The left (west) of the glacier are: 85°09′S 177°50′W  /  85.150°S 177.833°W  / -85.150; -177.833 . A broad glacier, about 12 nautical miles (22 km; 14 mi) long, flowing east between Mount Rosenwald and Mount Black to enter Shackleton Glacier just north of Matador Mountain . Named by US-ACAN after Commander F.S. Gallup, Jr., United States Navy. Commanding Officer of Squadron VX-6 during Operation Deep Freeze (OpDFrz) 1965. 85°06′S 177°10′W  /  85.100°S 177.167°W  / -85.100; -177.167 . A broad glacier, flowing generally eastward from

8881-514: 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

8988-473: 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

9095-414: 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

9202-561: 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,

9309-713: 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

9416-709: The northwest and Roberts Massif to the southeast. It is joined from the right (east) by Zaneveld Glacier, which also originates in the ice sheet. Further north it is joined from the right by the Logie Glacier, which flows west through the Cumulus Hills . Flowing north, the Shackleton Glacier is joined from the left (west) by the Gallup Glacier and the Baldwin Glacier and from the right (east) by McGregor Glacier just past Eckins Nunatak. The Swithinbank Moraine extends north from Matador Mountain along

9523-585: 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

9630-419: 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

9737-439: 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

9844-696: The right side of the snout. A temnospondyl [REDACTED] R. indet. Lower Fremouw A temnospondyl A. shackletoni Lower Fremouw Eight presacral vertebrae, left humerus, ribs, feet Medium-sized archosauriform Lower Fremouw Partial presacral vertebra and left humerus A large-bodied archosauriform reptile P. browni Lower Fremouw An enigmatic diapsid reptile; initially named Fremouwsaurus geludens P. trigoniceps Lower Fremouw A procolophonid reptile [REDACTED] P. broomi Lower Fremouw A prolacertiform reptile [REDACTED] Permian The Permian ( / ˈ p ɜːr m i . ə n / PUR -mee-ən )

9951-972: The south slopes of Anderson Heights in the Bush Mountains and flowing southeast to enter Shackleton Glacier at Thanksgiving Point . Discovered and photographed by USN OpHjp (1946–47) on the flights of Feb. 16, 1947. Named by US-ACAN for Master Sgt. A.V. Mincey, USMC, radio operator of Flight 8A. 84°47′S 177°00′W  /  84.783°S 177.000°W  / -84.783; -177.000 . A tributary glacier, 3 nautical miles (5.6 km; 3.5 mi) long, flowing east from Anderson Heights to enter Shackleton Glacier just south of Epidote Peak . Named by US-ACAN for Lieutenant George B. Held, Civil Engineer Corps, USN, Public Works Officer at McMurdo Station during 1964. 84°42′S 177°03′W  /  84.700°S 177.050°W  / -84.700; -177.050 . Steep-walled tributary glacier, 5 nautical miles (9.3 km; 5.8 mi) long, entering

10058-408: 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

10165-495: The southwest slopes of the Prince Olav Mountains and flowing west to enter Shackleton Glacier just north of Cumulus Hills. Named by the Southern Party of NZGSAE (1961–62) for V.R. McGregor, geologist with that party. 85°10′S 173°30′W  /  85.167°S 173.500°W  / -85.167; -173.500 . A tributary glacier 7 nautical miles (13 km; 8.1 mi) long, flowing northwest between

10272-532: 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

10379-523: The third land-based again. Shackleton Glacier Shackleton Glacier ( 84°35′S 176°20′W  /  84.583°S 176.333°W  / -84.583; -176.333 ) is a major Antarctic glacier, over 60 nautical miles (110 km; 69 mi) long and from 5 to 10 nautical miles (9.3 to 18.5 km; 5.8 to 11.5 mi) wide, descending from the Antarctic Plateau from the vicinity of Roberts Massif and flowing north through

10486-413: 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

10593-566: The upper part of Shackleton Glacier. Named by US-ACAN for Jacques S. Zaneveld, United States Antarctic Program (USARP) biologist at McMurdo Station, 1963–64 and 1964–65, who participated in the cruise of the USS Glacier , January-March 1965. 85°18′S 175°20′W  /  85.300°S 175.333°W  / -85.300; -175.333 . A tributary glacier, about 10 nautical miles (19 km; 12 mi) long and 2 nautical miles (3.7 km; 2.3 mi) wide, flowing west through

10700-658: The warming climate. Antarctica, while much warmer in the Early Triassic than it is today, was cooler than other parts of Gondwana and may have been more hospitable to tetrapod populations. Antarctica's milder climate allowed many groups to take refuge in the region while other populations experienced decline. In the Early Triassic, many Fremouw Formation tetrapods had smaller body sizes than their Permian ancestors, and many were adapted for burrowing. Both of these characteristics are seen as adaptations to Antarctica's greater seasonal variability and protracted day-night cycles. The first tetrapod , or land-living vertebrate, from Antarctica

10807-645: The west side of Shackleton Glacier opposite Gemini Nunataks. Named by the Texas Tech-Shackleton Glacier Party, 1964–65, for Helen Gerasimou, polar personnel specialist with the Office of Antarctic Programs, National Science Foundation . 84°39′S 177°10′W  /  84.650°S 177.167°W  / -84.650; -177.167 . A tributary glacier, 4 nautical miles (7.4 km; 4.6 mi) long, flowing east to enter Shackleton Glacier between Mount Franke and Mount Cole, in

10914-731: The west side of the Shackleton Glacier to the Gemini Nunataks. It crosses the mouths of the Gallup, Baldwin, Mincey and Field glaciers, left tributaries of the Shackleton Glacier. Past Lockhart Ridge the Shackleton Glacier is joined from the right by the Yeats Glacier. The glacier flows north through the Queen Maud Mountains, with the Anderson Heights to its west and the Cathedral Peaks to its east. Below

11021-560: The west slope of the Cumulus Hills between Landry Bluff and Halfmoon Bluff to enter Shackleton Glacier. Named by the Texas Tech Shackleton Glacier Expedition (1964–65) for S/Sgt. Donald R. Brunner, member of the U.S. Army Aviation Detachment which supported the expedition. 85°11′S 175°12′W  /  85.183°S 175.200°W  / -85.183; -175.200 . A small tributary glacier just southwest of Mount Kenyon , descending

11128-404: The west slopes of the Cumulus Hills to enter Shackleton Glacier. Named by US-ACAN for Lester F. Gillespie, USARP meteorologist at South Pole Station, winter 1962. 85°08′S 174°50′W  /  85.133°S 174.833°W  / -85.133; -174.833 . A tributary glacier, 14 nautical miles (26 km; 16 mi) long and 3 nautical miles (5.6 km; 3.5 mi) wide, draining

11235-520: Was found in the Fremouw Formation and described in 1968. It was represented by a small bone fragment that is probably part of the left mandible of a temnospondyl amphibian. The bone was found the previous year by a researcher from Ohio State University who was studying the geology of the Transantarctic Mountains. The animal was later named Austrobrachyops Jenseni . After its discovery, paleontological expeditions were launched to

11342-469: Was injured in an Otter airplane crash on Dec. 22, 1955, following take-off from the Cape Bird area. 84°33′S 175°12′W  /  84.550°S 175.200°W  / -84.550; -175.200 . A glacier, 11 nautical miles (20 km; 13 mi) long, flowing north between Waldron Spurs and Longhorn Spurs to enter the Ross Ice Shelf just east of the mouth of Shackleton Glacier. Named by

11449-667: 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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