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Moccasin Springs Formation
The Hunton Megagroup also Hunton Super Group, Hunton Group, Hunton Formation and Hunton Limestone is predominantly composed of carbonate rock, deposited between the Silurian and early to mid Devonian periods. In many States it acts as a reservoir for both hydrocarbons and water. Stratigraphy Clifty Limestone The Clifty Limestone is a Middle Devonian geologic formation in the Ozark Plateaus of Arkansas. This thin formation can but up to 4 feet thick. The name was introduced in 1916 by Albert Homer Purdue and Hugh Dinsmore Miser in their study of northern Arkansas. They designated a stratotype along the East Fork of Little Clifty Creek in Benton County, Arkansas. The Clifty Limestone is very sandy, light blue to bluish grey. Penters Chert The Penters Chert is a Devonian geologic formation in the Ozark Plateaus of Arkansas. Its thickness ranges up to 90'. The name was introduced in 1921 by Hugh Dinsmore Miser in his study of Arkansas. Miser designated a type locality near t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhuddanian
In the geologic timescale, the Rhuddanian is the first age of the Silurian Period and of the Llandovery Epoch. The Silurian is in the Paleozoic Era of the Phanerozoic Eon. The Rhuddanian Age began 443.8 ± 1.5 Ma and ended 440.8 ± 1.2 Ma (million years ago). It succeeds the Himantian Age (the last age of the Ordovician Period) and precedes the Aeronian Age. GSSP The GSSP for the Silurian is located in a section at Dob's Linn, Scotland, in an artificial excavation created just north of the Linn Branch Stream. Two lithological units ( formations) occur near the boundary. The lower is the Hartfell Shale ( thick), consisting chiefly of pale gray mudstone with subordinate black shales and several interbedded meta-bentonites. Above this is the thick Birkhill Shale, which consist predominantly of black graptolitic shale with subordinate gray mudstones and meta-bentonites. See also * Ordovician-Silurian extinction events * Early Palaeozoic Icehouse The Andean-Saharan glaciatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Formation (geology)
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 Wer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ozarkodina
''Ozarkodina'' is an extinct genus of conodonts in the family Spathognathodontidae. Use in stratigraphy ''Ozarkodina snajdri'' forms a subdivision of the '' Pseudomonoclimacis'' latilobus graptolite zone in the Burgsvik beds Silurian formation in Sweden. An ''Ozarkodina snajdri crispa'' zone has also been identified in the Wills Creek in Virginia. ''Ozarkodina derenjalensis'' is found in the Silurian of the Niur Formation in Iran.A new early Silurian prioniodontid conodont with three P elements from Iran and associated species. Peep Männik, C. Giles Miller and Vachik Hairapetian, Acta Palaeontologica Polonica, 2015, volume 60, issue 3, pages 733–746, The Kellwasser event in the Devonian which saw the extinction of all ''Ozarkodina'' species is reported in the list of Global Boundary Stratotype Sections and Points. References External links ''Ozarkodina''at fossilworks Fossilworks is a portal which provides query, download, and analysis tools to facilitate ac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acodus
''Acodus'' is an extinct genus of conodonts. Species * ''A. acutus'' * ''A. campanula'' * ''A. crassus'' * ''A. delicatus'' * ''A. deltatus'' * ''A. erectus'' * ''A. firmus'' * ''A. jonesi'' * ''A. kechikaensis'' * ''A. neodeltatus'' * ''A. oneotensis'' * ''A. planus'' * ''A. primitivus'' * ''A. sigmoideus'' * ''A. similaris'' * ''A. tripterolobus'' * ''A. zeballus'' Distribution Fossils of ''Acodus'' have been found in Argentina, Canada (Ontario, Quebec, British Columbia, Northwest Territories, Nunavut), China, Colombia (Tarqui, Huila),Moreno et al., 2008, p.10 the Czech Republic, Estonia, Iran, Kazakhstan, Malaysia, the Russian Federation, Spain, Sweden, Thailand, the United Kingdom, and the United States (Indiana, New York, Tennessee, Nevada, Kentucky, Missouri, Ohio, Utah).''Acodus'' at |
Conodont
Conodonts (Greek ''kōnos'', "cone", + ''odont'', "tooth") are an extinct group of agnathan (jawless) vertebrates resembling eels, classified in the class Conodonta. For many years, they were known only from their tooth-like oral elements, which are usually found in isolation and are now called conodont elements. Knowledge about soft tissues remains limited. They existed in the world's oceans for over 300 million years, from the Cambrian to the beginning of the Jurassic. Conodont elements are widely used as index fossils, fossils used to define and identify geological periods. The animals are also called Conodontophora (conodont bearers) to avoid ambiguity. Discovery and understanding of conodonts The teeth-like fossils of the conodont were first discovered by Heinz Christian Pander and the results published in Saint Petersburg, Russia, in 1856. The name ''pander'' is commonly used in scientific names of conodonts. It was only in the early 1980s that the first fossil evidence of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Izard County, Arkansas
Izard County is a county located in the U.S. state of Arkansas. As of the 2010 census, the population was 13,696. The county seat is Melbourne. Izard County is Arkansas's 13th county, formed on October 27, 1825, and named for War of 1812 General and Arkansas Territorial Governor George Izard. It is an alcohol prohibition or dry county. Geography According to the U.S. Census Bureau, the county has a total area of , of which is land and (0.6%) is water. Major highways * Arkansas Highway 5 * Arkansas Highway 9 * Arkansas Highway 56 * Arkansas Highway 58 * Arkansas Highway 69 * Arkansas Highway 69 Business * Arkansas Highway 177 * Arkansas Highway 223 * Arkansas Highway 289 * Arkansas Highway 354 Adjacent counties *Fulton County (north) * Sharp County (east) * Independence County (southeast) * Stone County (southwest) * Baxter County (northwest) Demographics 2020 census As of the 2020 United States census, there were 13,577 people, 4,851 households, and 3,124 familie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
