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Geology Of Lincolnshire
: ''This article describes the geology of the ceremonial county of Lincolnshire. Besides the modern administrative county, it includes the unitary authority areas of North Lincolnshire and North East Lincolnshire.'' The geology of Lincolnshire in eastern England largely consists of an easterly dipping succession of Mesozoic age sedimentary rocks, obscured across large parts of the county by unconsolidated deposits dating from the last few hundred thousand years of the present Quaternary Period. Triassic The oldest rocks exposed at or near the surface of Lincolnshire are the sandstones and mudstones of the early Triassic Sherwood Sandstone Group. Rocks from this and the overlying Mercia Mudstone and Penarth groups occur in the northwest of the county and along its western border but are generally concealed beneath a thick cover of recent deposits. Jurassic A range of rocks from the Jurassic Period occur within a broadly north-south outcrop which tapers markedly northwards from t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geology
Geology () is a branch of natural science concerned with Earth and other astronomical objects, the features or rocks of which it is composed, and the processes by which they change over time. Modern geology significantly overlaps all other Earth sciences, including hydrology, and so is treated as one major aspect of integrated Earth system science and planetary science. Geology describes the structure of the Earth on and beneath its surface, and the processes that have shaped that structure. It also provides tools to determine the relative and absolute ages of rocks found in a given location, and also to describe the histories of those rocks. By combining these tools, geologists are able to chronicle the geological history of the Earth as a whole, and also to demonstrate the age of the Earth. Geology provides the primary evidence for plate tectonics, the evolutionary history of life, and the Earth's past climates. Geologists broadly study the properties and processes of E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Fens
The Fens, also known as the , in eastern England are a naturally marshy region supporting a rich ecology and numerous species. Most of the fens were drained centuries ago, resulting in a flat, dry, low-lying agricultural region supported by a system of drainage channels and man-made rivers ( dykes and drains) and automated pumping stations. There have been unintended consequences to this reclamation, as the land level has continued to sink and the dykes have been built higher to protect it from flooding. Fen is the local term for an individual area of marshland or former marshland. It also designates the type of marsh typical of the area, which has neutral or alkaline water and relatively large quantities of dissolved minerals, but few other plant nutrients. The Fens are a National Character Area, based on their landscape, biodiversity, geodiversity and economic activity. The Fens lie inland of the Wash, and are an area of nearly in Lincolnshire, Cambridgeshire, and Norfol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wealden Group
The Wealden Group, occasionally also referred to as the Wealden Supergroup, is a group (a sequence of rock strata) in the lithostratigraphy of southern England. The Wealden group consists of paralic to continental (freshwater) facies sedimentary rocks of Berriasian to Aptian age and thus forms part of the English Lower Cretaceous. It is composed of alternating sands and clays. The sandy units were deposited in a flood plain of braided rivers, the clays mostly in a lagoonal coastal plain.Jackson (2008) The Wealden Group can be found in almost all Early Cretaceous basins of England: its outcrops curve from the Wessex Basin in the south to the Cleveland Basin in the northeast. It is not found in northwest England and Wales, areas which were at the time tectonic highs where no deposition took place. The same is true for the London Platform around London and Essex. Offshore, the Wealden Group can reach a thickness of 700 metres. The terms ''Wealden'' and ''Wealden facies'' are also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 the entire Phanerozoic. The name is derived from the Latin ''creta'', "chalk", which is abundant in the latter half of the period. It is usually abbreviated K, for its German translation ''Kreide''. The Cretaceous was a period with a relatively warm climate, resulting in high eustatic sea levels that created numerous shallow inland seas. These oceans and seas were populated with now- extinct marine reptiles, ammonites, and rudists, while dinosaurs continued to dominate on land. The world was ice free, and forests extended to the poles. During this time, new groups of mammals and birds appeared. During the Early Cretaceous, flowering plants appeared and began to rapidly diversify, becoming the dominant group of plants across the Earth b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lincoln Edge
The Lincoln Cliff or Lincoln Edge is a portion of a major escarpment that runs north–south through Lindsey and Kesteven in central Lincolnshire and is a prominent landscape feature in a generally flat portion of the county. Towards its northern end, near Scunthorpe, it is sometimes referred to as the Trent Cliff. The name preserves an obsolete sense of the word "cliff", which could historically refer to a hillside as well as a precipitous rock face. Description The scarp is formed by resistant Jurassic age rocks, principally the Lincolnshire Limestone Formation, and is remarkable for its length and straightness. However it is modest in height, rising about 50 metres or less above the surrounding landscape. It runs for over 50 miles from the Leicestershire border near Grantham to the Humber Estuary, and is broken only twice by river gaps at Ancaster and Lincoln, through which the rivers Slea and Witham respectively flow. To the west of the Cliff north of Lincoln lies the Rive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corallian Group
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 ... [...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 defined a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Great Oolite Group
The Great Oolite Group is a Middle Jurassic stratigraphic unit that outcrops in southern England. It consists of a complex set of marine deposits primarily mudstone and bioclastic ooidal and fine grained limestone, deposited in nearshore to shelf settings. It is exposed at the surface as a variably thick belt extending roughly NE-SW from the coast of Dorset up to the Humber. It is also present at depth in the Weald and Wessex Basins, as well as offshore. Several of the constituent formations, notably the Taynton Limestone Formation and the Forest Marble Formation are notable for their fossil content, including those of dinosaurs and pterosaurs and some of the earliest mammals. Paleofauna * '' Cardiodon rugulosus'' * ''Cetiosaurus oxoniensis'' * '' Eoplophysis vetustus'' (stegosaurid indet) * ''Megalosaurus bucklandii'' * ''Proceratosaurus bradleyi'' * '' Seldsienean megistorhynchus'' See also * List of dinosaur-bearing rock formations ** List of stratigraphic units with fe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inferior Oolite Group
The Inferior Oolite is a sequence of Jurassic age sedimentary rocks in Europe. It was deposited during the Middle Jurassic.Weishampel, David B; et al. (2004). "Dinosaur distribution (Middle Jurassic, Europe)." In: Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. Pp. 538–541. . The Inferior Oolite Group as more recently defined is a Jurassic lithostratigraphic group (a sequence of rock strata) in southern and eastern England . It has been variously known in the past as the Under Oolite (or Oolyte), the Inferior Oolite, the Inferior Oolite Series and the Redbourne Group. Outcrops The rocks are exposed from Dorset and Somerset eastwards and northwards through the English Midlands to Yorkshire. It is present at depth in the Wessex-Weald Basin, where it reaches its greatest thickness of 120 m. Lithology and stratigraphy The group consists of up to 120 m thickness of oolitic limestones and su ... [...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 d ... [...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 limes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
