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Corallian Oolite Formation
The Coralline Oolite Formation is a limestone formation of Oxfordian (Upper Jurassic) age, found in the Cleveland Basin of North Yorkshire, England. Coral Rag Member The rock forms some of the hills around Oxford and was once used as building stone. Coral rag can be seen in some of the oldest buildings in that city, including the Saxon tower of St Michael at the Northgate __NOTOC__ St Michael at the North Gate is a church in Cornmarket Street, at the junction with Ship Street, in central Oxford, England. The name derives from the church's location on the site of the north gate of Oxford when it was surrounded b ..., St George's Tower of Oxford Castle and the mediaeval walls of the city. Hambleton Oolite Member This ooidal limestone lies above either the Yedmandale Member or the Lower Calcareous Grit Formation. It is overlain by either the Middle Calcareous Grit or Malton Oolite Members. It is distinguished from the latter by its smaller grain-size and poorer sorting. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Formation (stratigraphy)
A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics (lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock exposed in a geographical region (the stratigraphic column). It is the fundamental unit of lithostratigraphy, the study of strata or rock layers. A formation must be large enough that it can be mapped at the surface or traced in the subsurface. Formations are otherwise not defined by the thickness (geology), thickness of their rock strata, which can vary widely. They are usually, but not universally, tabular in form. They may consist of a single lithology (rock type), or of alternating beds of two or more lithologies, or even a heterogeneous mixture of lithologies, so long as this distinguishes them from adjacent bodies of rock. The concept of a geologic formation goes back to the beginnings of modern scientific geology. The term was used by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
British Geological Survey
The British Geological Survey (BGS) is a partly publicly funded body which aims to advance geoscientific knowledge of the United Kingdom landmass and its continental shelf by means of systematic surveying, monitoring and research. The BGS headquarters are in Keyworth, Nottinghamshire, England. Its other centres are located in Edinburgh, Wallingford, Cardiff and London. The current motto of the BGS is: ''Gateway to the Earth''. History and previous names The Geological Survey was founded in 1835 by the Board of Ordnance as the Ordnance Geological Survey, under Henry De la Beche. This was the world's first national geological survey. It remained a branch of the Ordnance Survey for many years. In 1965, it was merged with the Geological Museum and Overseas Geological Surveys, under the name of Institute of Geological Sciences. On 1 January 1984, the institute was renamed the British Geological Survey (and often referred to as the BGS), a name still carried today. Competenc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theropoda
Theropoda (; ), whose members are known as theropods, is a dinosaur clade that is characterized by hollow bones and three toes and claws on each limb. Theropods are generally classed as a group of saurischian dinosaurs. They were ancestrally carnivorous, although a number of theropod groups evolved to become herbivores and omnivores. Theropods first appeared during the Carnian age of the late Triassic Period (geology), period 231.4 million years ago (Year#SI prefix multipliers, Ma) and included all the large terrestrial carnivores from the Early Jurassic until at least the close of the Cretaceous, about 66 Ma. In the Jurassic, birds evolved from small specialized coelurosaurian theropods, and are today represented by about 10,500 living species. Biology Diet and teeth Theropods exhibit a wide range of diets, from insectivores to herbivores and carnivores. Strict carnivory has always been considered the ancestral diet for theropods as a group, and a wider variety of di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Omosaurus
''Omosaurus'' is a dubious genus of extinct crurotarsan reptile, possibly a phytosaur, from the Late Triassic (Carnian) of North Carolina. Only scant remains are known, which makes ''Omosaurus'' hard to classify. The type, and only species, ''Omosaurus perplexus'', was named and described in 1856 by Joseph Leidy. Discovery and naming In the middle of the nineteenth century, geologist Professor Ebenezer Emmons discovered several reptilian teeth in the colliery of the Chatham company in North Carolina. In 1856, the fossils in his collection were described by paleontologist Joseph Leidy. Leidy combined the teeth with some vertebrae and ribs; adding to them an osteoderm or scute found in the same strata by Professor Michael Tuomey, he named the whole ''Omosaurus perplexus'' based on the holotype specimen BMNH 46013.J. Leidy, (1856), "Notice of remains of extinct vertebrated animals discovered by Professor E. Emmons", ''Proceedings of the Academy of Natural Sciences of Philadelphia' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stegosauridae
Stegosauridae is a family of thyreophoran dinosaurs (armoured dinosaurs) within the suborder Stegosauria. The clade is defined as all species of dinosaurs more closely related to ''Stegosaurus'' than ''Huayangosaurus''.David B. Weishampel, Peter Dodson, Halszka Osmólska. The ''Dinosauria'' (2nd ed.). Berkeley: University of California Press. The name ‘Stegosauridae’ is thus a stem-based name taken from the well-represented genus – ''Stegosaurus'' (meaning ‘roofed lizard’). Fossil evidence of stegosaurids, dating from the Middle Jurassic through the Early Cretaceous, have been recovered from North America, Eurasia and Africa. The clade Stegosauridae is composed of the genera ''Stegosaurus'', ''Dacentrurus'', '' Miragaia'', ''Loricatosaurus'', and ''Kentrosaurus'', with the last considered to be at the base of the clade. The stegosaurids like all other stegosaurians were quadrupedal herbivores that exhibited the characteristic stegosaurian dorsal dermal plates. These larg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cetiosaurus
''Cetiosaurus'' () meaning 'whale lizard', from the Greek '/ meaning 'sea monster' (later, 'whale') and '/ meaning 'lizard', is a genus of herbivorous sauropod dinosaur from the Middle Jurassic Period, living about 168 million years ago in what is now Europe. ''Cetiosaurus'' was in 1842 the first sauropod from which bones were described and is the most complete sauropod found in England. It was so named because its describer, Sir Richard Owen, supposed it was a marine creature, initially an extremely large crocodile, and did not recognise it for a land-dwelling dinosaur. Because of the early description many species would be named in the genus, eventually eighteen of them. Most of these have now been placed in other genera or are understood to be dubious names, based on poor fossil material. The last is true also of the original type species, ''Cetiosaurus medius'', and so ''C. oxoniensis'' was officially made the new type species in 2014. ''C. oxoniensis'' is based on three mor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sauropoda
Sauropoda (), whose members are known as sauropods (; from '' sauro-'' + '' -pod'', 'lizard-footed'), is a clade of saurischian ('lizard-hipped') dinosaurs. Sauropods had very long necks, long tails, small heads (relative to the rest of their body), and four thick, pillar-like legs. They are notable for the enormous sizes attained by some species, and the group includes the largest animals to have ever lived on land. Well-known genera include ''Brachiosaurus'', ''Diplodocus'', ''Apatosaurus'' and ''Brontosaurus''. The oldest known unequivocal sauropod dinosaurs are known from the Early Jurassic. ''Isanosaurus'' and ''Antetonitrus'' were originally described as Triassic sauropods, but their age, and in the case of ''Antetonitrus'' also its sauropod status, were subsequently questioned. Sauropod-like sauropodomorph tracks from the Fleming Fjord Formation (Greenland) might, however, indicate the occurrence of the group in the Late Triassic. By the Late Jurassic (150 million yea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxford Clay Formation
The Oxford Clay (or Oxford Clay Formation) is a Jurassic marine sedimentary rock formation underlying much of southeast England, from as far west as Dorset and as far north as Yorkshire. The Oxford Clay Formation dates to the Jurassic, specifically, the Callovian and Oxfordian ages, and comprises two main facies. The lower facies comprises the Peterborough Member, a fossiliferous organic-rich mudstone. This facies and its rocks are commonly known as lower Oxford Clay. The upper facies comprises the middle Oxford Clay, the Stewartby Member, and the upper Oxford Clay, the Weymouth Member. The upper facies is a fossil poor assemblage of calcareous mudstones. Oxford Clay appears at the surface around Oxford, Peterborough and Weymouth and is exposed in many quarries around these areas. The top of the Lower Oxford Clay shows a lithological change, where fissile shale changes to grey mudstone. The Middle and Upper Oxford Clays differ slightly, as they are separated by an argillaceou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metriacanthosaurus
''Metriacanthosaurus'' (meaning "moderately-spined lizard") is a genus of metriacanthosaurid dinosaur from the upper Oxford Clay of England, dating to the Late Jurassic period, about 160 million years ago (lower Oxfordian). History of discovery In 1923, German paleontologist Friedrich von Huene wrote a paper on Jurassic and Cretaceous European carnivorous dinosaurs within Saurischia. In this paper, he examined a specimen (OUM J.12144) including an incomplete hip, a leg bone, and part of a backbone, assigning it to a new species of ''Megalosaurus'': ''Megalosaurus parkeri''. The specific name honours W. Parker who in the nineteenth century had collected the fossils near Jordan's Cliff at Weymouth. These bones were from the Oxford Clay Formation, which dates to the Upper Jurassic. In 1932, however, von Huene concluded it was a species of '' Altispinax'', ''A. parkeri''. In 1964, scientist Alick Walker decided these fossils were too different from ''Altispinax'', as they lacke ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Placeholder
Placeholder may refer to: Language * Placeholder name, a term or terms referring to something or somebody whose name is not known or, in that particular context, is not significant or relevant. * Filler text, text generated to fill space or provide unremarkable and/or standardised text. * Lorem ipsum, a standard Latin text most commonly used to demonstrate a font, typography or layout. Mathematics and computer science * Free variable, a symbol subsequently replaced by a value or string. * Interpoled variable of a ''string interpolation'' process. * Metasyntactic variable, a placeholder name (see above) as used in computer science. * Format placeholder, used in computing to format strings within print functions (printf). Other uses * Line stander, a person standing in a queue for another. * Placeholder (politics), a person temporarily appointed to an office that would otherwise remain vacant. See also * Filler (other) * Spacer (other) * Stand-in * S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oolite
Oolite or oölite (''egg stone'') is a sedimentary rock formed from ooids, spherical grains composed of concentric layers. The name derives from the Ancient Greek word for egg (ᾠόν). Strictly, oolites consist of ooids of diameter 0.25–2 millimetres; rocks composed of ooids larger than 2 mm are called pisolites. The term ''oolith'' can refer to oolite or individual ooids. Composition Ooids are most commonly composed of calcium carbonate ( calcite or aragonite), but can be composed of phosphate, clays, chert, dolomite or iron minerals, including hematite. Dolomitic and chert ooids are most likely the result of the replacement of the original texture in limestone. Oolitic hematite occurs at Red Mountain near Birmingham, Alabama, along with oolitic limestone. They are usually formed in warm, supersaturated, shallow, highly agitated marine water intertidal environments, though some are formed in inland lakes. The mechanism of formation starts with a small fragment of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
