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Lashly Mountains
The Lashly Mountains () are a small group of mountains, the most prominent at being Mount Crean, standing south of the head of Taylor Glacier and west of Lashly Glacier, in Victoria Land, Antarctica. Exploration and naming The Lashly Mountains were discovered by the British National Antarctic Expedition (1901–04) and named for William Lashly, a member of the party which explored this area. Location The Lashley Mountains are on the edge of the East Antarctic Ice Sheet. They are west of the Quartermain Mountains and Mount Feather, from which they are separated by the Lashly Glacier, which flows south into The Portal. Mount Crean is the highest peak of the range. Portal Mountain lies to the south of the range, above the Skelton Névé. Geology The Lashly Mountains lie between the intrusive rocks of the McMurdo Dry Valleys and the extrusive rocks of the Transantarctic Mountains. Samples from an unnamed nunatak north of Mount Crean indicated an extrusive origin. The Lashly F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antarctica
Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean, it contains the geographic South Pole. Antarctica is the fifth-largest continent, being about 40% larger than Europe, and has an area of . Most of Antarctica is covered by the Antarctic ice sheet, with an average thickness of . Antarctica is, on average, the coldest, driest, and windiest of the continents, and it has the highest average elevation. It is mainly a polar desert, with annual precipitation of over along the coast and far less inland. About 70% of the world's freshwater reserves are frozen in Antarctica, which, if melted, would raise global sea levels by almost . Antarctica holds the record for the lowest measured temperature on Earth, . The coastal regions can reach temperatures over in summer. Native species of animals include mites, nematodes, penguins, seals and tardigrades. Where ve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transantarctic Mountains
The Transantarctic Mountains (abbreviated TAM) comprise a mountain range of uplifted (primarily sedimentary) rock in Antarctica which extend, with some interruptions, across the continent from Cape Adare in northern Victoria Land to Coats Land. These mountains divide East Antarctica and West Antarctica. They include a number of separately named mountain groups, which are often again subdivided into smaller ranges. The range was first sighted by James Clark Ross in 1841 at what was later named the Ross Ice Shelf in his honour. It was first crossed during the British National Antarctic Expedition of 1901-1904. Geography The mountain range stretches between the Ross Sea and the Weddell Sea, the entire width of Antarctica, hence the name. With a total length of about , the Transantarctic Mountains are one of the longest mountain ranges on Earth. The Antarctandes are even longer, having in common with the Transantarctic Mountains the ranges from Cape Adare to the Queen Maud Moun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tabular Mountain
The Quartermain Mountains are a group of exposed mountains in Antarctica, about long, typical of ice-free features of the McMurdo Dry Valleys, Victoria Land, located south of Taylor Glacier and bounded by Finger Mountain, Mount Handsley, Mount Feather and Tabular Mountain; also including Knobhead, Terra Cotta Mountain, New Mountain, Beacon Heights, Pyramid Mountain, Arena Valley, Kennar Valley, Turnabout Valley and the several valleys and ridges within Beacon Valley. Exploration The mountains were visited by British expeditions led by Robert Falcon Scott (1901–04 and 1910–13) and Ernest Shackleton (1907–09), who applied several names. Names were added in the years subsequent to the International Geophysical Year, 1957–58, concurrent with research carried out by New Zealand Antarctic Research Programme and United States Antarctic Research Program field parties, and to fulfill the requirement for maps compiled from United States Navy aerial photographs, 1947–83 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
British Antarctic Expedition, 1910–13
The ''Terra Nova'' Expedition, officially the British Antarctic Expedition, was an expedition to Antarctica which took place between 1910 and 1913. Led by Captain Robert Falcon Scott, the expedition had various scientific and geographical objectives. Scott wished to continue the scientific work that he had begun when leading the ''Discovery'' Expedition from 1901 to 1904, and wanted to be the first to reach the geographic South Pole. He and four companions attained the pole on 17 January 1912, where they found that a Norwegian team led by Roald Amundsen had preceded them by 34 days. Scott's party of five died on the return journey from the pole; some of their bodies, journals, and photographs were found by a search party eight months later. The expedition, named after its supply ship, was a private venture financed by public contributions and a government grant. It had further backing from the Admiralty, which released experienced seamen to the expedition, and from the Royal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tom Crean (explorer)
Thomas Crean ( ga, Tomás Ó Cuirín; 16 February 1877 – 27 July 1938) was an Irish seaman and Antarctic explorer who was awarded the Albert Medal for Lifesaving (AM). Crean was a member of three major expeditions to Antarctica during the Heroic Age of Antarctic Exploration, including Robert Falcon Scott's 1911–1913 Terra Nova Expedition. This saw the race to reach the South Pole lost to Roald Amundsen and ended in the deaths of Scott and his party. During the expedition, Crean's solo walk across the Ross Ice Shelf to save the life of Edward Evans led to him receiving the Albert Medal. Crean left the family farm near Annascaul, in County Kerry, to enlist in the Royal Navy at age 16. In 1901, while serving on ''Ringarooma'' in New Zealand, he volunteered to join Scott's 1901–1904 Discovery Expedition to Antarctica, thus beginning his exploring career. After his experience on the ''Terra Nova'', Crean's third and final Antarctic venture was as second officer on Er ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New Zealand Antarctic Place-Names Committee
New Zealand Antarctic Place-Names Committee (NZ-APC) is an adjudicating committee established to authorize the naming of features in the Ross Dependency on the Antarctic continent. It is composed of the members of the New Zealand Geographic Board plus selected specialists on Antarctica. This committee works in collaboration with similar place-naming authorities in Australia, Great Britain and the United States to reach concurrence on each decision. The NZ-APC committee was established in 1956. Names attributed by the committee * Alberich Glacier, named after Alberich, king of the elves and chief of the Nibelungen * Arena Saddle, named in conjunction with Arena Valley * Brawhm Pass, named after the six party members of the University of New South Wales expeditions of 1964–65 and 1966–67 * Caliper Cove, named for descriptive features * Canada Stream, named in conjunction with Canada Glacier * Cape Crossfire, named for descriptive features * Cuneiform Cliffs, named for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conchostracans
Clam shrimp are a group of bivalved branchiopod crustaceans that resemble the unrelated bivalved molluscs. They are extant and also known from the fossil record, from at least the Devonian period and perhaps before. They were originally classified in the former order Conchostraca, which later proved to be paraphyletic and was subsumed into the superorder Diplostraca. Clam shrimp now make up three of the seven orders in Diplostraca, Cyclestherida, Laevicaudata, and Spinicaudata, in addition to the fossil family Leaiidae. Characteristics Both valves of the shell are held together by a strong closing muscle. The animals react to danger by contracting the muscle, so that the valves close tightly and the crustacean, as if dead, lies motionlessly at the bottom of the pool. In most species the head is dorsoventrally compressed. The sessile compound eyes are close together and located on the forehead; in the genus ''Cyclestheria'' they are truly fused. In front of them is a simple n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Archaeopteris
''Archaeopteris'' is an extinct genus of progymnosperm tree with fern-like leaves. A useful index fossil, this tree is found in strata dating from the Upper Devonian to Lower Carboniferous (), the oldest fossils being 385 million years old, and had global distribution. Until the 2007 discovery of '' Wattieza'', many scientists considered ''Archaeopteris'' to be the earliest known tree. Bearing buds, reinforced branch joints, and branched trunks similar to today's wood, it is more reminiscent of modern seed-bearing trees than other spore bearing taxa; It combines characteristics of woody trees and herbaceous ferns, and belongs to the progymnosperms, a group of extinct plants with gymnosperm-like wood but that produce spores rather than seeds. Taxonomy John William Dawson described the genus in 1871. The name derives from the ancient Greek (''archaīos'', "ancient"), and (''ptéris'', "fern"). ''Archaeopteris'' was originally classified as a fern, and it remained classifi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phytolith
Phytoliths (from Greek, "plant stone") are rigid, microscopic structures made of silica, found in some plant tissues and persisting after the decay of the plant. These plants take up silica from the soil, whereupon it is deposited within different intracellular and extracellular structures of the plant. Phytoliths come in varying shapes and sizes. Although some use "phytolith" to refer to all mineral secretions by plants, it more commonly refers to siliceous plant remains. In contrast, mineralized calcium secretions in cacti are composed of calcium oxalates.Piperno, Dolores R. (2006). Phytoliths: A Comprehensive Guide for Archaeologists and Paleoecologists. AltaMira Press . The silica is absorbed in the form of monosilicic acid (Si(OH)4), and is carried by the plant's vascular system to the cell walls, cell lumen, and intercellular spaces. Depending on the plant taxa and soil condition, absorbed silica can range from 0.1% to 10% of the plant's total dry weight. When deposit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triassic
The Triassic ( ) is a geologic period and system which spans 50.6 million years from the end of the Permian Period 251.902 million years ago (Mya), to the beginning of the Jurassic Period 201.36 Mya. The Triassic is the first and shortest period of the Mesozoic Era. Both the start and end of the period are marked by major extinction events. The Triassic Period is subdivided into three epochs: Early Triassic, Middle Triassic and Late Triassic. The Triassic began in the wake of the Permian–Triassic extinction event, which left the Earth's biosphere impoverished; it was well into the middle of the Triassic before life recovered its former diversity. Three categories of organisms can be distinguished in the Triassic record: survivors from the extinction event, new groups that flourished briefly, and other new groups that went on to dominate the Mesozoic Era. Reptiles, especially archosaurs, were the chief terrestrial vertebrates during this time. A specialized subgroup of arch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dicroidium
''Dicroidium'' is an extinct genus of fork-leaved seed ferns that were widely distributed over Gondwana during the Triassic (). Their fossils are known from South Africa, the Arabian Peninsula, Australia, New Zealand, South America, Madagascar, the Indian subcontinent and Antarctica. They were first discovered in Triassic sediments of Tasmania by Morris in 1845. Fossils from the Umm Irna Formation in Jordan and in Pakistan indicate that these plants already existed in Late Permian. Late surviving members of the genus are known from the Early Jurassic ( Sinemurian) of East Antarctica. Within paleobotany, ''Dicroidium'' is a form genus used to refers to the leaves, associated with ovuluate organs classified as ''Umkomasia'' and pollen organs classified as ''Pteruchus,'' while ''Dicroidum'' is also used collectively to refer to the whole plant. Description The leaves are similar to those of modern ferns but like all seed ferns (Pteridospermatophyta) were thick and had substantial ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beacon Supergroup
The Beacon Supergroup is a geological formation exposed in Antarctica and deposited from the Devonian to the Triassic (). The unit was originally described as either a formation or sandstone, and upgraded to group and supergroup as time passed. It contains a sandy member known as the Beacon Heights Orthoquartzite. Overview The base of the Beacon Supergroup is marked by an unconformity and is composed of the Devonian Taylor Group, a quartzose sandstone sequence; and the Late Carboniferous to Early Jurassic Victoria Group, consisting of glacial beds, sandstone, shale, conglomerate, and coal. The Beacon Sandstone was named by Hartley T. Ferrar during Scott's Discovery Expedition (1901–1904), using the Beacon Heights survey points as reference. ''Glossopteris'' fossils dated the sandstone to the Permian and linked the lithology to similar sequences on neighboring continents. Generally flat lying, the supergroup is up to 3.2 km thick and is fairly continuous from south Victo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
