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Lambeth Group
The Lambeth Group is a stratigraphic group, a set of geological rock strata in the London and Hampshire Basins of southern England. It comprises a complex of vertically and laterally varying gravels, sands, silts and clays deposited between 56-55 million years before present during the Ypresian age (lower Eocene). It is found throughout the London Basin with a thickness between 10m and 30m and the Hampshire Basin with a thickness between 50m and less than 25m. Although this sequence only crops out in these basins, the fact that it underlies 25% of London at a depth of less than 30m means the formation is of engineering interest for tunnelling and foundations. History The formation was first known as the Plastic Clay by T. Webster in 1816 after the Argile plastique of Georges Cuvier and A. Brongniart. It was called the Mottled Clay by Joseph Prestwich in 1846, but in 1853 he proposed the name Woolwich-and-Reading Beds to emphasise the differing local aspects of the series. This ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Woolwich Formation
The Woolwich Formation is a Formation (geology), geological formation in southeast England. It preserves fossils dating back to the Paleogene Period (geology), period. See also * List of fossiliferous stratigraphic units in England References * Paleogene England {{England-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
London Basin
The London Basin is an elongated, roughly triangular sedimentary basin approximately long which underlies London and a large area of south east England, south eastern East Anglia and the adjacent North Sea. The basin formed as a result of compressional tectonics related to the Alpine orogeny during the Palaeogene period and was mainly active between 40 and 60 million years ago. Boundaries and shape Spatial boundaries The generally accepted boundaries are the Late Cretaceous Chalk Group's escarpments of the Chilterns and Marlborough Downs to the north and the North Downs and Berkshire Downs to the south. To the south lie the Weald and Salisbury Plain and to the north is the Vale of Aylesbury. The approximate western limit is in the Marlborough area of Wiltshire. The eastern end merges with the North Sea Basin, extending on land along the north Kent coast to Reculver and up the east coast of Essex and into Suffolk, where it is overlain by Pleistocene 'Crag' deposits which cov ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sandstone
Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates) because they are the most resistant minerals to weathering processes at the Earth's surface. Like uncemented sand, sandstone may be any color due to impurities within the minerals, but the most common colors are tan, brown, yellow, red, grey, pink, white, and black. Since sandstone beds often form highly visible cliffs and other topographic features, certain colors of sandstone have been strongly identified with certain regions. Rock formations that are primarily composed of sandstone usually allow the percolation of water and other fluids and are porous enough to store large quantities, making them valuable aquifers and petroleum reservoirs. Quartz-bearing sandstone can be changed into quartzite through metamorphism, usually relate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clay
Clay is a type of fine-grained natural soil material containing clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4). Clays develop plasticity when wet, due to a molecular film of water surrounding the clay particles, but become hard, brittle and non–plastic upon drying or firing. Most pure clay minerals are white or light-coloured, but natural clays show a variety of colours from impurities, such as a reddish or brownish colour from small amounts of iron oxide. Clay is the oldest known ceramic material. Prehistoric humans discovered the useful properties of clay and used it for making pottery. Some of the earliest pottery shards have been dated to around 14,000 BC, and clay tablets were the first known writing medium. Clay is used in many modern industrial processes, such as paper making, cement production, and chemical filtering. Between one-half and two-thirds of the world's population live or work in buildings made with clay, oft ... [...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 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 Abraham Gottlob We ... [...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] |
Joseph Prestwich
Sir Joseph Prestwich, FRS (12 March 1812 – 23 June 1896) was a British geologist and businessman, known as an expert on the Tertiary Period and for having confirmed the findings of Boucher de Perthes of ancient flint tools in the Somme valley gravel beds. Biography Born in Clapham, Prestwich was educated in Paris and Reading before entering University College, London where he studied chemistry and natural philosophy. Whilst a student he founded the short-lived Zetetical Society. In 1830 he began working for the family wine business. This job required him to travel throughout the United Kingdom and also abroad to France and Belgium, and during the course of these travels he made many geological observations. He became a Fellow of Geological Society in 1833 and published his first paper there two years later. His 1836 memoir on the ''Geology of Coalbrookdale'', based upon observations made during 1831 and 1832, established his reputation as a geologist. From 1846 hi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alexandre Brongniart
Alexandre Brongniart (5 February 17707 October 1847) was a French chemist, mineralogist, geologist, paleontologist, and zoologist, who collaborated with Georges Cuvier on a study of the geology of the region around Paris. Observing fossil content as well as lithology in sequences, he classified Tertiary formations and was responsible for defining 19th century geological studies as a subject of science by assembling observations and classifications. Brongniart was also the founder of the Musée national de Céramique-Sèvres (National Museum of Ceramics), having been director of the Sèvres Porcelain Factory from 1800 to 1847. Life He was born in Paris, the son of the architect Alexandre-Théodore Brongniart and father of the botanist Adolphe-Théodore Brongniart. In 1797, he became an instructor of natural history at the Central School of the Four Nations, and became the professor of mineralogy in 1822 at the Museum of Natural History in Paris. He was appointed in 1800 by N ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Georges Cuvier
Jean Léopold Nicolas Frédéric, Baron Cuvier (; 23 August 1769 – 13 May 1832), known as Georges Cuvier, was a French naturalist and zoologist, sometimes referred to as the "founding father of paleontology". Cuvier was a major figure in natural sciences research in the early 19th century and was instrumental in establishing the fields of comparative anatomy and paleontology through his work in comparing living animals with fossils. Cuvier's work is considered the foundation of vertebrate paleontology, and he expanded Linnaean taxonomy by grouping classes into phyla and incorporating both fossils and living species into the classification. Cuvier is also known for establishing extinction as a fact—at the time, extinction was considered by many of Cuvier's contemporaries to be merely controversial speculation. In his ''Essay on the Theory of the Earth'' (1813) Cuvier proposed that now-extinct species had been wiped out by periodic catastrophic flooding events. In this way, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thomas Webster (geologist)
Thomas Webster (11 February 177226 December 1844) was a Scottish geologist. Life Webster was born in Orkney in 1772, probably at Kirkwall, and was educated at Aberdeen. He subsequently went to London and studied architecture, the Royal Institution in Albemarle Street being built from his design, and where in 1830 he delivered the Royal Institution Christmas Lecture. In 1826 he was appointed house-secretary and curator to the Geological Society of London, and for many years he rendered important services in editing and illustrating the ''Transactions'' of the Society. In 1841–42 he was professor of geology in University College, London. He was an accomplished water-colour painter and was elected an honorary member of the Sketch Society. He contributed articles about Architecture and Aquatinta to ''Rees's Cyclopædia''. ''An Encyclopaedia of Domestic Economy'', a comprehensive guide to running a household which Webster had compiled with the help of a Mrs. Parkes, was published ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eocene
The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', " dawn") and (''kainós'', "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch. The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope 13C in the atmosphere was exceptionally low in comparison with the more common isotope 12C. The end is set at a major extinction event called the ''Grande Coupure'' (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Siberia and in what is now Chesapeake Bay. As with other geologic periods, the strata that define the start and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Age (geology)
The geologic time scale, or geological time scale, (GTS) is a representation of time based on the rock record of Earth. It is a system of chronological dating that uses chronostratigraphy (the process of relating strata to time) and geochronology (scientific branch of geology that aims to determine the age of rocks). It is used primarily by Earth scientists (including geologists, paleontologists, geophysicists, geochemists, and paleoclimatologists) to describe the timing and relationships of events in geologic history. The time scale has been developed through the study of rock layers and the observation of their relationships and identifying features such as lithologies, paleomagnetic properties, and fossils. The definition of standardized international units of geologic time is the responsibility of the International Commission on Stratigraphy (ICS), a constituent body of the International Union of Geological Sciences (IUGS), whose primary objective is to precisely de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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