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Fossil Beach (Sedbury Cliffs)
Fossil Beach, at Sedbury, Gloucestershire, England, is beneath the Sedbury Cliffs by the River Severn and is known as a rich source of easily discovered fossils. It is within the Severn Estuary Site of Special Scientific Interest (SSSI). Access and safety The grassy flats of the coast are accessible from the public footpaths, which lead from Beachley Road (by the bus stop) through the fields and woods, the easiest from the end of Buttington Terrace through two galvanised kissing gates for about 500m, but also from the end of the Offa's Dyke Path. Fossil Beach is then about a 700-m walk to the left, north-east along the coastal grass and through the reeds; the walk is frequently marshy and muddy so Wellington boots are recommended. Larger rocks can be slippery to walk on (Universal Transverse Mercator coordinates: 31U 475148 5720571; latitude/longitude: 51.63560 N, 2.64090 E; ). The foreshore is subject to the broad tidal range of the Severn Estuary so it is advisable to check th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Forest Of Dean (UK Parliament Constituency)
Forest of Dean is a Constituencies of the Parliament of the United Kingdom, constituency in Gloucestershire represented in the British House of Commons, House of Commons of the Parliament of the United Kingdom, UK Parliament since 2005 United Kingdom general election, 2005 by Mark Harper, a Conservative Party (UK), Conservative who has served as Secretary of State for Transport since 2022. Boundaries 1885–1918: The Sessional Divisions of Coleford, Lydney, Newent, and Newnham. 1918–1950: The Urban Districts of Awre, Coleford, Newnham, and Westbury-on-Severn, the Rural Districts of East Dean and United Parishes, Lydney, Newent, and West Dean, and part of the Rural District of Gloucester. 1997–2010: The District of Forest of Dean, and the Borough of Tewkesbury wards of Haw Bridge and Highnam. 2010–present: The District of Forest of Dean, and the Borough of Tewkesbury ward of Highnam with Haw Bridge. The constituency boundaries remained unchanged. History This seat was ... [...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] |
Norian
The Norian is a division of the Triassic Period. It has the rank of an age ( geochronology) or stage (chronostratigraphy). It lasted from ~227 to million years ago. It was preceded by the Carnian and succeeded by the Rhaetian. Stratigraphic definitions The Norian was named after the Noric Alps in Austria. The stage was introduced into scientific literature by Austrian geologist Edmund Mojsisovics von Mojsvar in 1869. The Norian Stage begins at the base of the ammonite biozones of '' Klamathites macrolobatus'' and '' Stikinoceras kerri'', and at the base of the conodont biozones of '' Metapolygnathus communisti'' and '' Metapolygnathus primitius''. A global reference profile for the base (a GSSP) had in 2009 not yet been appointed. The top of the Norian (the base of the Rhaetian) is at the first appearance of ammonite species '' Cochloceras amoenum''. The base of the Rheatian is also close to the first appearance of conodont species '' Misikella spp.'' and '' Epigondolell ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mercia Mudstone Group
The Mercia Mudstone Group is an early Triassic lithostratigraphic group (a sequence of rock strata) which is widespread in Britain, especially in the English Midlands – the name is derived from the ancient kingdom of Mercia which corresponds to that area. It is frequently encountered in older literature as the Keuper Marl or Keuper Marl Series. The Mercia Mudstone Group is now divided into five formations recognised and mappable across its entire outcrop and subcrop. The formations are a mix of mudstones, siltstones, sandstones and halites. Historically this sequence of rocks has been subdivided in different ways with different names in each of the basinal areas in which it is found. Increasing knowledge of the sequences and the more recent development of seamless electronic mapping by the British Geological Survey (BGS) necessitated a reappraisal of these divisions. A report published by BGS in 2008 recommended the abandonment of previous divisions and naming schemes in favour ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Penarth Group
The Penarth Group is a Rhaetian age (Triassic) lithostratigraphic group (a sequence of rock strata) which is widespread in Britain. It is named from the seaside town of Penarth near Cardiff in south Wales where strata of this age are exposed in coastal cliffs southwards to Lavernock Point. This sequence of rocks was previously known as the Rhaetic or Rhaetic Beds. Stratigraphy It includes the Lilstock Formation and the underlying Westbury Formation. The Langport and Cotham Members, grey limestones of marine origin with associated mudstones, are recognised within the Lilstock Formation, itself named from Lilstock in west Somerset. The Westbury Formation is named from Westbury-on-Severn in Gloucestershire. Ireland In 1999, the discovery of an ichthyosaur from Langport Member mudstones exposed at Waterloo Bay, Larne provided the most complete example of this in Northern Ireland Northern Ireland ( ga, Tuaisceart Éireann ; sco, label=Ulster-Scots, Norlin Airlann) is a par ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Westbury Formation
The Westbury Formation is a geological formation in England, one of the Penarth Group. It dates back to the Rhaetian.Weishampel, David B; et al. (2004). "Dinosaur distribution (Late Triassic, Europe)." In: Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. Pp. 521–525. . The formation is named after the village of Westbury-on-Severn in Gloucestershire. The remains of giant shastasaurids are known from the formation. Vertebrate fauna *''Avalonianus'' *''Picrodon'' * Shastasauridae indet. See also * List of dinosaur-bearing rock formations This list of dinosaur-bearing rock formations is a list of geologic formations in which dinosaur fossils have been documented. Containing body fossils * List of stratigraphic units with dinosaur body fossils ** List of stratigraphic units with f ... References {{Reflist Triassic System of Europe Rhaetian Stage Geologic formations of England ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lilstock Formation
The Lilstock Formation is a Formation (geology), geologic formation in England. It preserves bivalve, insect and other invertebrate fossils, as well as fossil fish of ''Agkistracanthus, Agkistracanthus mitgelensis'' and the basal theropod dinosaur ''Newtonsaurus, Newtonsaurus cambrensis'' dating back to the Rhaetian of the Triassic Period (geology), period. White Lias The White lias is a rare, fine-grained form of limestone from the late Triassic period, occurring only in certain parts of Somerset and infrequently in Warwickshire. It gets the name ‘lias’ from the quarrymen's dialect for ‘layers’, referring to its natural state when quarried. White lias is part of the Langport Member of the Lilstock Formation, a multi-layered bed of stone formed from shale and limestone. At its base is a bone-bed yielding ancient marine, reptilian and ammonite fossils. White lias varies in colour from white-cream to pale grey and is traditionally used for building and flooring. Evidence ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cotham Formation
The Lilstock Formation is a geologic formation in England. It preserves bivalve, insect and other invertebrate fossils, as well as fossil fish of '' Agkistracanthus mitgelensis'' and the basal theropod dinosaur '' Newtonsaurus cambrensis'' dating back to the Rhaetian of the Triassic period. White Lias The White lias is a rare, fine-grained form of limestone from the late Triassic period, occurring only in certain parts of Somerset and infrequently in Warwickshire. It gets the name ‘lias’ from the quarrymen's dialect for ‘layers’, referring to its natural state when quarried. White lias is part of the Langport Member of the Lilstock Formation, a multi-layered bed of stone formed from shale and limestone. At its base is a bone-bed yielding ancient marine, reptilian and ammonite fossils. White lias varies in colour from white-cream to pale grey and is traditionally used for building and flooring. Evidence of its use can be seen in manor houses, churches and cathedrals all ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lias Group
The Lias Group or Lias is a lithostratigraphic unit (a sequence of rock strata) found in a large area of western Europe, including the British Isles, the North Sea, the Low Countries and the north of Germany. It consists of marine limestones, shales, marls and clays. ''Lias'' is a Middle English term for hard limestone, used in this specific sense by geologists since 1833. In the past, geologists used ''Lias'' not only for the sequence of rock layers, but also for the timespan during which they were formed. It was thus an alternative name for the Early Jurassic epoch of the geologic timescale. It is now more specifically known that the Lias is Rhaetian to Toarcian in age (over a period of 20 million years between ) and thus also includes a part of the Triassic. The use of the name "Lias" for a unit of time is therefore slowly disappearing. Subdivisions In southern England, the Lias Group is often divided into Lower, Middle and Upper subgroups. In Southern England the Lias is ... [...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 defi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mudstone
Mudstone, a type of mudrock, is a fine-grained sedimentary rock whose original constituents were clays or muds. Mudstone is distinguished from ''shale'' by its lack of fissility (parallel layering).Blatt, H., and R.J. Tracy, 1996, ''Petrology.'' New York, New York, W. H. Freeman, 2nd ed, 529 pp. The term ''mudstone'' is also used to describe carbonate rocks ( limestone or dolomite) that are composed predominantly of carbonate mud. However, in most contexts, the term refers to siliciclastic mudstone, composed mostly of silicate minerals. The NASA Curiosity rover has found deposits of mudstone on Mars that contain organic substances such as propane, benzene and toluene. Definition There is not a single definition of mudstone that has gained general acceptance,Boggs 2006, p.143 though there is wide agreement that mudstones are fine-grained sedimentary rocks, composed mostly of silicate grains with a grain size less than . Individual grains this size are too small to be distin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limestone
Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms when these minerals precipitate out of water containing dissolved calcium. This can take place through both biological and nonbiological processes, though biological processes, such as the accumulation of corals and shells in the sea, have likely been more important for the last 540 million years. Limestone often contains fossils which provide scientists with information on ancient environments and on the evolution of life. About 20% to 25% of sedimentary rock is carbonate rock, and most of this is limestone. The remaining carbonate rock is mostly dolomite, a closely related rock, which contains a high percentage of the mineral dolomite, . ''Magnesian limestone'' is an obsolete and poorly-defined term used variously for dolomite, for lime ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
