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Corallian
The Corallian Group or Corallian Limestone is a geologic group in England. It is predominantly a coralliferous sedimentary rock, laid down in the Oxfordian stage of the Jurassic. It is a hard variety of "coral rag". Building stones from this geological structure tend to be irregular in shape. It is often found close to seams of Portland Limestone (e.g. Abbotsbury in Dorset, England). It is a younger limestone than its near-neighbour, the Oolitic, as found in the Cotswolds, in Gloucestershire. It is laterally equivalent to and interfingers with units of the Ancholme Group. A ridge of Corallian Limestone rises above the Vale of Avon and the Thames Valley in its Oxfordshire stretch. The Oxfordshire Corallian ridge is an escarpment holding back the hanging valley that is the Vale of White Horse and its hardness forced the River Thames to take a wide northern detour, to cut through the low ridge at Oxford. High points along the ridge are Cumnor Hurst and Wytham Hill. The outcrop k ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bran Point
Bran Point is a small headland on the Dorset coast in southern England, about halfway between the small villages of Ringstead to the east and Osmington Mills to the west. There is a picturesque cliff-top path between the two villages via Bran Point. The name derives from the brown colouring of the rock forming the cliffs of the headland, caused in part by residual oil deposits.Watson, D. F.; Hindle, A. D. and Farrimond P. (2000) "Organic geochemistry of petroleum seepages within the Jurassic Bencliff Grit, Osmington Mills, Dorset, UK" ''Petroleum Geoscience'' 6(4): pp. 289-297 The geology of the area is particularly interesting. The coastline in the area is formed from rocks and shingle with exposed cliffs behind. The Middle White Oolite of the Osmington Oolite more visible to the west has descended to beach level here. At the middle of the cliff, there is nodular rubble consisting of calcitized sponge spicules. Higher in the cliff are reddish brown beds containing ''Trigonia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coralline 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 Oxford () is a city in England. It is the county town and only city of Oxfordshire. In 2020, its population was estimated at 151,584. It is north-west of London, south-east of Birmingham and north-east of Bristol. The city is home to the ... 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, 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] |
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 argilla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Faringdon Sand
The Faringdon Sand is a geologic formation in England. It preserves fossils dating back to the Cretaceous period. See also * List of fossiliferous stratigraphic units in England See also *Lists of fossiliferous stratigraphic units in Europe * Lists of fossiliferous stratigraphic units in the United Kingdom References * {{DEFAULTSORT:Fossiliferous stratigraphic units in England England England is a country ... References Cretaceous England Aptian Stage Lower Cretaceous Series of Europe {{England-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ampthill Clay
The Ampthill Clay is a Mesozoic geologic formation in southern England. Dinosaur remains diagnostic to the genus level are among the fossils that have been recovered from the formation.Weishampel, et al. (2004). "Dinosaur distribution." Pp. 517-607. Vertebrate paleofauna * ''Cryptosaurus eumerus'' "Femur.""Table 17.1," in Weishampel, et al. (2004). Page 367. See also * List of dinosaur-bearing rock formations ** List of stratigraphic units with few dinosaur genera This list of stratigraphic units with few non-avian dinosaur genera includes Mesozoic stratigraphic units of formation rank or higher that have produced dinosaur body fossils which have been referred to at most five genera. Since taxonomy freque ... Footnotes References * Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. 861 pp. . Oxfordian Stage {{UK-geologic-formation-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kimmeridge Clay Formation
The Kimmeridge Clay is a sedimentary deposit of fossiliferous marine clay which is of Late Jurassic to lowermost Cretaceous age and occurs in southern and eastern England and in the North Sea. This rock formation is the major source rock for North Sea oil. The fossil fauna of the Kimmeridge Clay includes turtles, crocodiles, sauropods, plesiosaurs, pliosaurs and ichthyosaurs, as well as a number of invertebrate species. Description Kimmeridge Clay is named after the village of Kimmeridge on the Dorset coast of England, where it is well exposed and forms part of the Jurassic Coast World Heritage Site. Onshore, it is of Late Jurassic (Kimmeridgian) age and outcrops across England, in a band stretching from Dorset in the south-west, north-east to North Yorkshire. Offshore, it extends into the Lower Cretaceous (Berriasian Stage) and it is found throughout the Southern, Central and Northern North Sea. The foundations of the Humber Bridge on the southern (Barton) side of the bri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stanford Formation
The Stanford Formation is a geologic formation in England. It preserves fossils dating back to the Oxfordian stage of the Middle Jurassic period, around 160 million years ago. See also * List of fossiliferous stratigraphic units in England See also * Lists of fossiliferous stratigraphic units in Europe * Lists of fossiliferous stratigraphic units in the United Kingdom References * {{DEFAULTSORT:Fossiliferous stratigraphic units in England England England is a Countri ... References * Jurassic England Jurassic System of Europe Oxfordian Stage {{England-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kingston Formation
The Kingston Formation is a geologic formation in England. It preserves fossils dating back to the Jurassic period. See also * List of fossiliferous stratigraphic units in England See also * Lists of fossiliferous stratigraphic units in Europe * Lists of fossiliferous stratigraphic units in the United Kingdom References * {{DEFAULTSORT:Fossiliferous stratigraphic units in England England United Kingdom geology-rel ... References * Jurassic England Oxfordian Stage Jurassic System of Europe {{England-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cleveland Basin
The Cleveland Basin is a sedimentary basin in Yorkshire, England. Formed initially by rifting during the Mississippian period of the Early Carboniferous. It is West–East trending and lies between the intrabasinal highs of the Askrigg Block and the Market Weighton Axis, passing eastwards offshore into the Sole Pit Basin. It contains a thick development of the Bowland Shale, which has been assessed as being a major potential source of shale gas. It was inverted towards the end of the Carboniferous and most of the Upper Carboniferous sequence was eroded off. Subsequent deposition has also created a thick fill of Jurassic and Cretaceous The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of ... sediments. References Sedimentary basins of Europe {{UK-geology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siltstone
Siltstone, also known as aleurolite, is a clastic sedimentary rock that is composed mostly of silt. It is a form of mudrock with a low clay mineral content, which can be distinguished from shale by its lack of fissility.Blatt ''et al.'' 1980, pp.381-382 Although its permeability and porosity is relatively low, siltstone is sometimes a tight gas reservoir rock, an unconventional reservoir for natural gas that requires hydraulic fracturing for economic gas production. Siltstone was prized in ancient Egypt for manufacturing statuary and cosmetic palettes. The siltstone quarried at Wadi Hammamat was a hard, fine-grained siltstone that resisted flaking and was almost ideal for such uses. Description There is not complete agreement on the definition of siltstone. One definition is that siltstone is mudrock (clastic sedimentary rock containing at least 50% clay and silt) in which at least 2/3 of the clay and silt fraction is composed of silt-sized particles. Silt is define ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jurassic
The Jurassic ( ) is a geologic period and stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately Mya. The Jurassic constitutes the middle period of the Mesozoic Era and is named after the Jura Mountains, where limestone strata from the period were first identified. The start of the Jurassic was marked by the major Triassic–Jurassic extinction event, associated with the eruption of the Central Atlantic Magmatic Province. The beginning of the Toarcian Stage started around 183 million years ago and is marked by an extinction event associated with widespread oceanic anoxia, ocean acidification, and elevated temperatures likely caused by the eruption of the Karoo-Ferrar large igneous provinces. The end of the Jurassic, however, has no clear boundary with the Cretaceous and is the only boundary between geological periods to remain formally undefined. By the beginning of the Jurassi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
