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Midlands Microcraton
The Midlands Microcraton is a triangular block of late Neoproterozoic crust of igneous and volcaniclastic origin which underlies the English Midlands. Its northern tip is at the southern edge of the English Peak District and its other two corners are in the vicinity of London and Swansea. Though its northeastern edge is obscured by Palaeozoic and Mesozoic The Mesozoic Era ( ), also called the Age of Reptiles, the Age of Conifers, and colloquially as the Age of the Dinosaurs is the second-to-last era of Earth's geological history, lasting from about , comprising the Triassic, Jurassic and Cretace ... strata, the northwestern edge of the microcraton is clearly defined by the Welsh Borderland Fault System. To the south it is bounded by the Variscan Orogen.British Geological Survey 1996 ''Tectonic map of Britain, Ireland and adjacent areas'' Pharaoh, T.C. et al 1:1,500,000 (Keyworth, Nottingham: BGS) References {{DEFAULTSORT:Midlands Microcraton Cratons Structural geolo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Craton
A craton (, , or ; from grc-gre, κράτος "strength") is an old and stable part of the continental lithosphere, which consists of Earth's two topmost layers, the crust and the uppermost mantle. Having often survived cycles of merging and rifting of continents, cratons are generally found in the interiors of tectonic plates; the exceptions occur where geologically recent rifting events have separated cratons and created passive margins along their edges. Cratons are characteristically composed of ancient crystalline basement rock, which may be covered by younger sedimentary rock. They have a thick crust and deep lithospheric roots that extend as much as several hundred kilometres into Earth's mantle. Terminology The term ''craton'' is used to distinguish the stable portion of the continental crust from regions that are more geologically active and unstable. Cratons are composed of two layers: A continental '' shield'', in which the basement rock crops out at the surfa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palaeozoic
The Paleozoic (or Palaeozoic) Era is the earliest of three geologic eras of the Phanerozoic Eon. The name ''Paleozoic'' ( ;) was coined by the British geologist Adam Sedgwick in 1838 by combining the Greek words ''palaiós'' (, "old") and ''zōḗ'' (), "life", meaning "ancient life" ). It is the longest of the Phanerozoic eras, lasting from , and is subdivided into six geologic periods (from oldest to youngest): # Cambrian # Ordovician # Silurian # Devonian # Carboniferous # Permian The Paleozoic comes after the Neoproterozoic Era of the Proterozoic Eon and is followed by the Mesozoic Era. The Paleozoic was a time of dramatic geological, climatic, and evolutionary change. The Cambrian witnessed the most rapid and widespread diversification of life in Earth's history, known as the Cambrian explosion, in which most modern phyla first appeared. Arthropods, molluscs, fish, amphibians, reptiles, and synapsids all evolved during the Paleozoic. Life began in the ocean but ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geology Of Europe
The geology of Europe is varied and complex, and gives rise to the wide variety of landscapes found across the continent, from the Scottish Highlands to the rolling plains of Hungary. Europe's most significant feature is the dichotomy between highland and mountainous Southern Europe and a vast, partially underwater, northern plain ranging from England in the west to the Ural Mountains in the east. These two halves are separated by the Pyrenees and the Alps-Carpathians mountain chain. The northern plains are delimited in the west by the Scandinavian Mountains and the mountainous parts of the British Isles. The southern mountainous region is bounded by the Mediterranean Sea and the Black Sea. Major shallow water bodies submerging parts of the northern plains are the Celtic Sea, the North Sea, the Baltic Sea and the Barents Sea. From the standpoint of plate tectonics, the ongoing northward drive of the African plate into the Eurasian plate in the Mediterranean basin is the most promin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Structural Geology
Structural geology is the study of the three-dimensional distribution of rock units with respect to their deformational histories. The primary goal of structural geology is to use measurements of present-day rock geometries to uncover information about the history of deformation ( strain) in the rocks, and ultimately, to understand the stress field that resulted in the observed strain and geometries. This understanding of the dynamics of the stress field can be linked to important events in the geologic past; a common goal is to understand the structural evolution of a particular area with respect to regionally widespread patterns of rock deformation (e.g., mountain building, rifting) due to plate tectonics. Use and importance The study of geologic structures has been of prime importance in economic geology, both petroleum geology and mining geology. Folded and faulted rock strata commonly form traps that accumulate and concentrate fluids such as petroleum and natural gas. Sim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cratons
A craton (, , or ; from grc-gre, κράτος "strength") is an old and stable part of the continental lithosphere, which consists of Earth's two topmost layers, the crust and the uppermost mantle. Having often survived cycles of merging and rifting of continents, cratons are generally found in the interiors of tectonic plates; the exceptions occur where geologically recent rifting events have separated cratons and created passive margins along their edges. Cratons are characteristically composed of ancient crystalline basement rock, which may be covered by younger sedimentary rock. They have a thick crust and deep lithospheric roots that extend as much as several hundred kilometres into Earth's mantle. Terminology The term ''craton'' is used to distinguish the stable portion of the continental crust from regions that are more geologically active and unstable. Cratons are composed of two layers: A continental ''shield'', in which the basement rock crops out at the surface, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Variscan Orogeny
The Variscan or Hercynian orogeny was a geologic mountain-building event caused by Late Paleozoic continental collision between Euramerica (Laurussia) and Gondwana to form the supercontinent of Pangaea. Nomenclature The name ''Variscan'', comes from the Medieval Latin name for the district ''Variscia'', the home of a Germanic tribe, the Varisci; Eduard Suess, professor of geology at the University of Vienna, coined the term in 1880. ( Variscite, a rare green mineral first discovered in the Vogtland district of Saxony in Germany, which is in the Variscan belt, has the same etymology.) ''Hercynian'', on the other hand, derives from the Hercynian Forest. Both words were descriptive terms of strike directions observed by geologists in the field, ''variscan'' for southwest to northeast, ''hercynian'' for northwest to southeast. The ''variscan'' direction reflected the direction of ancient fold belts cropping out throughout Germany and adjacent countries and the meaning shifted from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Welsh Borderland Fault System
The Welsh Borderland Fault System is a zone of faulting and associated folding which runs northeastwards through Wales from Pembrokeshire through Carmarthenshire and Powys into Shropshire in England. It comprises the Tywi Lineament, Pontesford Lineament and Church Stretton Fault Zone. The southern margin of the fault system is defined by the Church Stretton Fault and Dulas Valley Fault, amongst others whilst its northern margin is defined by the Garth-Llanwrtyd Fault Belt in Carmarthenshire. The Church Stretton Fault component of the system is deemed to form the terrane boundary between the Cymru Terrane to its northwest and the Wrekin Terrane to its southeast. The system was active during the Caledonian Orogeny and was reactivated during the later Variscan Orogeny The Variscan or Hercynian orogeny was a geologic mountain-building event caused by Late Paleozoic continental collision between Euramerica (Laurussia) and Gondwana to form the supercontinent of Pangaea. Nomen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesozoic
The Mesozoic Era ( ), also called the Age of Reptiles, the Age of Conifers, and colloquially as the Age of the Dinosaurs is the second-to-last era of Earth's geological history, lasting from about , comprising the Triassic, Jurassic and Cretaceous Periods. It is characterized by the dominance of archosaurian reptiles, like the dinosaurs; an abundance of conifers and ferns; a hot greenhouse climate; and the tectonic break-up of Pangaea. The Mesozoic is the middle of the three eras since complex life evolved: the Paleozoic, the Mesozoic, and the Cenozoic. The era began in the wake of the Permian–Triassic extinction event, the largest well-documented mass extinction in Earth's history, and ended with the Cretaceous–Paleogene extinction event, another mass extinction whose victims included the non-avian dinosaurs, pterosaurs, mosasaurs, and plesiosaurs. The Mesozoic was a time of significant tectonic, climatic, and evolutionary activity. The era witnessed the gradual ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Swansea
Swansea (; cy, Abertawe ) is a coastal city and the second-largest city of Wales Wales ( cy, Cymru ) is a country that is part of the United Kingdom. It is bordered by England to the east, the Irish Sea to the north and west, the Celtic Sea to the south west and the Bristol Channel to the south. It had a population in .... It forms a Principal areas of Wales, principal area, officially known as the City and County of Swansea ( cy, links=no, Dinas a Sir Abertawe). The city is the List of cities in the United Kingdom, twenty-fifth largest in the United Kingdom. Located along Swansea Bay in southwest Wales, with the principal area covering the Gower Peninsula, it is part of the Swansea Bay (region), Swansea Bay region and part of the Historic counties of Wales, historic county of Glamorgan; also the ancient Welsh commote of Gŵyr. The principal area is the second most List of Welsh principal areas by population, populous local authority area in Wales with an estimate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neoproterozoic
The Neoproterozoic Era is the unit of geologic time from 1 billion to 538.8 million years ago. It is the last era of the Precambrian Supereon and the Proterozoic Eon; it is subdivided into the Tonian, Cryogenian, and Ediacaran periods. It is preceded by the Mesoproterozoic Era and succeeded by the Paleozoic Era of the Phanerozoic Eon. The most severe glaciation known in the geologic record occurred during the Cryogenian, when ice sheets may have reached the equator and formed a "Snowball Earth". The earliest fossils of complex multicellular life are found in the Ediacaran Period. These organisms make up the Ediacaran biota, including the oldest definitive animals in the fossil record. According to Rino and co-workers, the sum of the continental crust formed in the Pan-African orogeny and the Grenville orogeny makes the Neoproterozoic the period of Earth's history that has produced most continental crust. Geology At the onset of the Neoproterozoic the supercontinent Rod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
London
London is the capital and List of urban areas in the United Kingdom, largest city of England and the United Kingdom, with a population of just under 9 million. It stands on the River Thames in south-east England at the head of a estuary down to the North Sea, and has been a major settlement for two millennia. The City of London, its ancient core and financial centre, was founded by the Roman Empire, Romans as ''Londinium'' and retains its medieval boundaries.See also: Independent city#National capitals, Independent city § National capitals The City of Westminster, to the west of the City of London, has for centuries hosted the national Government of the United Kingdom, government and Parliament of the United Kingdom, parliament. Since the 19th century, the name "London" has also referred to the metropolis around this core, historically split between the Counties of England, counties of Middlesex, Essex, Surrey, Kent, and Hertfordshire, which largely comprises Greater London ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peak District
The Peak District is an upland area in England at the southern end of the Pennines. Mostly in Derbyshire, it extends into Cheshire, Greater Manchester, Staffordshire, West Yorkshire and South Yorkshire. It includes the Dark Peak, where moorland is found and the geology is dominated by gritstone, and the White Peak, a limestone area with valleys and gorges. The Dark Peak forms an arc on the north, east and west sides; the White Peak covers central and southern tracts. The historic Peak District extends beyond the National Park, which excludes major towns, quarries and industrial areas. It became the first of the national parks of England and Wales in 1951. Nearby Manchester, Stoke-on-Trent, Derby and Sheffield send millions of visitors – some 20 million live within an hour's ride. Inhabited from the Mesolithic era, it shows evidence of the Neolithic, Bronze and Iron Ages. Settled by the Romans and Anglo-Saxons, it remained largely agricultural; mining arose in the Middle Ages ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
