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Thiviers-Payzac Unit
The Thiviers-Payzac Unit is a metasedimentary succession of late Neoproterozoic and Cambrian age outcropping in the southern Limousin in France. The unit geologically forms part of the Variscan basement of the northwestern Massif Central. Terminology The Thiviers-Payzac Unit, sometimes still called ''Thiviers-Payzac Nappe'' or ''Bas-Limousin Group'', was named after Thiviers and Payzac, two small towns in the northeastern Dordogne situated within the unit's outcrop area. The term nappe is somewhat misleading. Geography Geographically the Thiviers-Payzac Unit belongs to the Bas-Limousin (southern Limousin), a plateau peneplained during the Eocene and whose elevation barely reaches above 400 metres. The unit starts just west of Thiviers in the northern Dordogne and then follows for 70 kilometres a semicircular arc segment, passing through Lanouaille, Payzac, Orgnac, Donzenac and finishing just east of Brive in the Corrèze. In the beginning the unit follows a WNW-ESE ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metasediment
In geology, metasedimentary rock is a type of metamorphic rock. Such a rock was first formed through the deposition and solidification of sediment Sediment is a naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of wind, water, or ice or by the force of gravity acting on the particles. For example, sand an .... Then, the rock was buried underneath subsequent rock and was subjected to high pressures and temperatures, causing the rock to recrystallize. The overall composition of a metasedimentary rock can be used to identify the original sedimentary rock, even where they have been subject to high-grade metamorphism and intense deformation. Types of metasedimentary rocks See also * References Metamorphic petrology {{petrology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orgnac-sur-Vézère
Orgnac-sur-Vézère (, literally ''Orgnac on Vézère''; oc, Ornhac de Vesera) is a commune in the Corrèze department in central France. Population See also *Communes of the Corrèze department The following is a list of the 279 communes of the Corrèze department of France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of Overseas France, overseas regions ... References Communes of Corrèze {{Corrèze-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pennsylvanian (geology)
The Pennsylvanian ( , also known as Upper Carboniferous or Late Carboniferous) is, in the International Commission on Stratigraphy, ICS geologic timescale, the younger of two period (geology), subperiods (or upper of two system (stratigraphy), subsystems) of the Carboniferous Period. It lasted from roughly . As with most other geochronology, geochronologic units, the stratum, rock beds that define the Pennsylvanian are well identified, but the exact date of the start and end are uncertain by a few hundred thousand years. The Pennsylvanian is named after the U.S. state of Pennsylvania, where the coal-productive beds of this age are widespread. The division between Pennsylvanian and Mississippian (geology), Mississippian comes from North American stratigraphy. In North America, where the early Carboniferous beds are primarily marine limestones, the Pennsylvanian was in the past treated as a full-fledged geologic period between the Mississippian and the Permian. In parts of Europe, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Génis Unit
The Génis Unit is a Paleozoic metasedimentary succession of the southern Limousin and belongs geologically to the Variscan basement of the French Massif Central. The unit covers the age range Cambrian/ Ordovician till Devonian. Type locality The Génis Unit was named after its type locality, the small town Génis, situated in the northeastern Dordogne. Geographical Occurrence The Génis Unit occurs in an elongated strip at the northeastern edge of the Dordogne department, following a WNW-ESE direction for about 26 kilometres. Its width across strike is not more than 5 kilometres. The unit forms part of the Bas Limousin, a basement plateau that was peneplained during the Paleogene. The plateau's elevation oscillates between 300 and 400 meters. Geologically the unit's northern limit is the South Limousin Fault, a very important ductile, dextral wrench fault separating the Génis Unit from the Thiviers-Payzac Unit to the north. To the south the unit is overlain by lias ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
