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South Wales Coal Measures Group
The South Wales Coal Measures Group is a lithostratigraphy, lithostratigraphical group (stratigraphy), term referring to the coal-bearing succession of rock stratum, strata which occur in South Wales within the Westphalian (stage), Westphalian stage (stratigraphy), Stage of the Carboniferous period (geology), Period. The Group name is also applied to rocks of similar age across southern England from the Bristol Coalfield east to the concealed Oxfordshire Coalfield, Oxfordshire, Berkshire Coalfield, Berkshire and Kent Coalfields. In formal use, the term replaces the earlier Coal Measures Group The Group comprises the: :* South Wales Upper Coal Measures Formation :* South Wales Middle Coal Measures Formation :* South Wales Lower Coal Measures Formation The term 'Productive Coal Measures' was formerly used for this succession. Note that, other than a 0-30m thick sequence immediately above the ''Cambriense'' Marine Band, the South Wales rock sequence which had formerly been assigned t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Group (stratigraphy)
In geology, a group is a lithostratigraphic unit consisting of a series of related formations that have been classified together to form a group. Formations are the fundamental unit of stratigraphy. Groups may sometimes be combined into supergroups. Groups are useful for showing relationships between formations, and they are also useful for small-scale mapping or for studying the stratigraphy of large regions. Geologists exploring a new area have sometimes defined groups when they believe the strata within the groups can be divided into formations during subsequent investigations of the area. It is possible for only some of the strata making up a group to be divided into formations. An example of a group is the Glen Canyon Group, which includes (in ascending order) the Wingate Sandstone, the Moenave Formation, the Kayenta Formation, and the Navajo Sandstone. Each of the formations can be distinguished from its neighbor by its lithology, but all were deposited in the same vast ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stage (stratigraphy)
In chronostratigraphy, a stage is a succession of rock strata laid down in a single age on the geologic timescale, which usually represents millions of years of deposition. A given stage of rock and the corresponding age of time will by convention have the same name, and the same boundaries. Rock series are divided into stages, just as geological epochs are divided into ages. Stages can be divided into smaller stratigraphic units called chronozones. (See chart at right for full terminology hierarchy.) Stages may also be divided into substages or indeed grouped as superstages. The term faunal stage is sometimes used, referring to the fact that the same fauna (animals) are found throughout the layer (by definition). Definition Stages are primarily defined by a consistent set of fossils (biostratigraphy) or a consistent magnetic polarity (see paleomagnetism) in the rock. Usually one or more index fossils that are common, found worldwide, easily recognized, and limited to a sing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bolsovian
The Westphalian is a stage in the regional stratigraphy of northwest Europe with an age between roughly 313 and 304 Ma (million years ago). It is a subdivision of the Carboniferous system or period and the regional Silesian series. The Westphalian is named for the region of Westphalia (German: ''Westfalen'') in western Germany where strata of this age occur. The Coal Measures of England and Wales are also largely of Westphalian age though they also extend into the succeeding Stephanian. The Westphalian age is preceded by the Namurian stage/age (which corresponds to the Millstone Grit Series of Great Britain) and succeeded by the Stephanian stage/age (which corresponds to the uppermost part of the Coal Measures of Great Britain). In the official geologic timescale of the ICS, the Westphalian is placed within the Pennsylvanian epoch (318-299 Ma).F M Gradstein, J G Ogg, A G Smith et al 2004, ‘A Geologic Time Scale 2004’. The (regionally defined) Westphalian stage correspon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Red Bed
Red beds (or redbeds) are sedimentary rocks, typically consisting of sandstone, siltstone, and shale, that are predominantly red in color due to the presence of ferric oxides. Frequently, these red-colored sedimentary strata locally contain thin beds of Conglomerate (geology), conglomerate, marl, limestone, or some combination of these sedimentary rocks. The ferric oxides, which are responsible for the red color of red beds, typically occur as a coating on the grains of sediments comprising red beds. Classic examples of red beds are the Permian and Triassic strata of the western United States and the Devonian Old Red Sandstone facies of Europe. Primary red beds Primary red beds may be formed by the erosion and redeposition of red soils or older red beds, but a fundamental problem with this hypothesis is the relative scarcity of red-colored source sediments of suitable age close to an area of red-bed sediments in Geology of Cheshire, Cheshire, England. Primary red beds may als ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Devonian
The Devonian ( ) is a geologic period and system of the Paleozoic era, spanning 60.3 million years from the end of the Silurian, million years ago (Mya), to the beginning of the Carboniferous, Mya. It is named after Devon, England, where rocks from this period were first studied. The first significant adaptive radiation of life on dry land occurred during the Devonian. Free-sporing vascular plants began to spread across dry land, forming extensive forests which covered the continents. By the middle of the Devonian, several groups of plants had evolved leaves and true roots, and by the end of the period the first seed-bearing plants appeared. The arthropod groups of myriapods, arachnids and hexapods also became well-established early in this period, after starting their expansion to land at least from the Ordovician period. Fish reached substantial diversity during this time, leading the Devonian to often be dubbed the Age of Fishes. The placoderms began dominating ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Namurian
The Namurian is a stage in the regional stratigraphy of northwest Europe with an age between roughly 326 and 313 Ma (million years ago). It is a subdivision of the Carboniferous system or period and the regional Silesian series. The Namurian is named for the Belgian city and province of Namur where strata of this age occur (part of the Belgian Coal Measures). The Millstone Grit Group in the lithostratigraphy of northern England and parts of Wales is also of Namurian age. The Namurian age lasted from 326 to 313 million years ago. It is preceded by the Visean stage/age (which corresponds to the upper Carboniferous Limestone of Great Britain) and succeeded by the Westphalian stage/age (which corresponds to the lower and middle Coal Measures of Great Britain). In the official geologic timescale of the International Commission on Stratigraphy (ICS), the Namurian straddles the boundary between the Mississippian epoch (359-318 Ma) and the Pennsylvanian epoch (318-299 Ma). The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grovesend Formation
Grovesend ( cy, Pengelli; ) is a village in the community of Grovesend and Waungron ( cy, Pengelli a Waungron), City and County of Swansea in Wales. The community has a population of 1,131. Retrieved 9 January 2010 Over the last 100 years Grovesend has gone through the transition of being a big mining community to a quiet semi rural village. It is mainly a residential community, with the major amenity being the welfare club. Locals often travel to nearby areas such as |
Pennant Sandstone Formation
Pennant may refer to: Flag or banner * Pennon (or pennant), a narrow, tapering flag ** Commissioning pennant, the traditional sign of a warship, flown from its masthead while the ship is in commission ** Broad pennant, flown from the masthead of a British Royal Navy ship to indicate the presence of a commodore on board ** Pennant (church), flown by navies during services on board ships * Pennant number, a number used to identify ships by the British Royal Navy and other navies of Europe and the Commonwealth * Pennant (sports), a commemorative flag displayed or flown by a league-winning team ** Pennant race, the race to clinch the division title in a regular baseball season * Pennant, a reference to Flag and pennant patterns in technical analysis of a stock market chart Places * Pennant, Ceredigion, Wales * Pennant, Powys, Wales * Pennant, Saskatchewan, Canada * Pennant Point, Nova Scotia, Canada * Pennant Hills, New South Wales, Australia People * Dafydd Pennant (16th c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coal Measures Group
The Coal Measures Group is a lithostratigraphical term coined to refer to the coal-bearing succession of rock strata which occur in the United Kingdom within the Westphalian Stage of the Carboniferous Period. Other than in Northern Ireland the term is now obsolete in formal use and is replaced by the Pennine Coal Measures Group, Scottish Coal Measures Group and the South Wales Coal Measures Group for the three distinct depositional provinces of the British mainland. Pennine Coal Measures Group Within the Pennine Basin the Pennine Coal Measures Group is preceded (underlain) by the Millstone Grit Group which is of Namurian age. It is succeeded (overlain) by the Warwickshire Group which comprises a largely non-productive sequence of red beds. It comprises the: :* Pennine Upper Coal Measures Formation :* Pennine Middle Coal Measures Formation :* Pennine Lower Coal Measures Formation The 'Pennine Basin' includes all of the coalfields of northern England and the English Midlan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Berkshire Coalfield
Berkshire ( ; in the 17th century sometimes spelt phonetically as Barkeshire; abbreviated Berks.) is a historic county in South East England. One of the home counties, Berkshire was recognised by Queen Elizabeth II as the Royal County of Berkshire in 1957 because of the presence of Windsor Castle, and letters patent were issued in 1974. Berkshire is a county of historic origin, a ceremonial county and a non-metropolitan county without a county council. The county town is Reading. The River Thames formed the historic northern boundary, from Buscot in the west to Old Windsor in the east. The historic county, therefore, includes territory that is now administered by the Vale of White Horse and parts of South Oxfordshire in Oxfordshire, but excludes Caversham, Slough and five less populous settlements in the east of the Royal Borough of Windsor and Maidenhead. All the changes mentioned, apart from the change to Caversham, took place in 1974. The towns of Abingdon, Didcot, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
