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Iapetognathus
''Iapetognathus'' is a genus of cordylodan conodonts. It is one of the oldest denticulate euconodont genera known.The conodont Iapetognathus and its value for defining the base of the Ordovician System. Frederick Miller, John E. Repetski, Robert S. Nicoll, Godfrey Nowlan and Raymond L. Ethington, GFF, Volume 136, Issue 1, 2014, pages 185-188, Like other members of the genus, ''Iapetognathus fluctivagus'' had ramiform (branching) array of elements (apparatus). It is believed that the ramiform apparatus in ''Iapetognathus fluctivagus'' evolved from the coniform (cone-like) apparatus of '' Iapetonudus ibexensis''. It can be readily distinguished from other conodonts existing during the same age by the sideward orientation of the major teeth-like projections (denticulate processes). The genus ''Iapetognathus'' and related denticulate groups still require extensive taxonomic clarification. In 2011, a study discovered that the First appearance datum (FAD) of ''Iapetognathus flucti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iapetognathus Fluctivagus
''Iapetognathus fluctivagus'' is a species of denticulate cordylodan conodonts belonging to the genus '' Iapetognathus''. It existed during the Tremadocian Age ( million years ago) of the Ordovician. It is an important index fossil in biostratigraphy. Description Like other members of the genus, ''Iapetognathus fluctivagus'' had ramiform (branching) array of elements (apparatus). It is believed that the ramiform apparatus in ''Iapetognathus fluctivagus'' evolved from the coniform (cone-like) apparatus of '' Iapetonudus ibexensis''. It can be readily distinguished from other conodonts existing during the same age by the sideward orientation of the major teeth-like projections (denticulate processes). Taxonomy ''Iapetognathus fluctivagus'' is classified under the genus '' Iapetognathus''. It belongs to the cordylodan family Cordylodontidae of the order Proconodontida (Cavidonti). It was first described in 1999 by paleontologists Robert S. Nicoll, James F. Miller, Godfrey S. No ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iapetognathus Preaengensis
''Iapetognathus'' is a genus of cordylodan conodonts. It is one of the oldest denticulate euconodont genera known.The conodont Iapetognathus and its value for defining the base of the Ordovician System. Frederick Miller, John E. Repetski, Robert S. Nicoll, Godfrey Nowlan and Raymond L. Ethington, GFF, Volume 136, Issue 1, 2014, pages 185-188, Like other members of the genus, ''Iapetognathus fluctivagus'' had ramiform (branching) array of elements (apparatus). It is believed that the ramiform apparatus in ''Iapetognathus fluctivagus'' evolved from the coniform (cone-like) apparatus of '' Iapetonudus ibexensis''. It can be readily distinguished from other conodonts existing during the same age by the sideward orientation of the major teeth-like projections (denticulate processes). The genus ''Iapetognathus'' and related denticulate groups still require extensive taxonomic clarification. In 2011, a study discovered that the First appearance datum (FAD) of ''Iapetognathus flucti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iapetonudus Ibexensis
''Iapetonudus'' is an extinct genus of conodonts. Like other members of its genus, ''Iapetognathus fluctivagus'' had ramiform (branching) array of elements (apparatus). It is believed that the ramiform apparatus in ''Iapetognathus fluctivagus'' evolved from the coniform (cone-like) apparatus of ''Iapetonudus ibexensis''. See also * Iapetus Ocean The Iapetus Ocean (; ) was an ocean that existed in the late Neoproterozoic and early Paleozoic eras of the geologic timescale (between 600 and 400 million years ago). The Iapetus Ocean was situated in the southern hemisphere, between the paleoco ..., an ocean that existed in the late Neoproterozoic and early Paleozoic eras of the geologic timescale (between 600 and 400 million years ago) References External links Proconodontida genera Early Ordovician animals Ordovician conodonts {{conodont-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cordylodontidae
Cordylodontidae is a family of conodonts. Genera are ''Cordylodus''. '' Eoconodontus'' and '' Iapetognathus''. References * The conodont apparatus as a food-gathering mechanism. Maurits Lindström, palaeontology, volume17, part 4, pages 729-744 * Taxonomy, Evolution, and Biostratigraphy of Conodonts from the Kechika Formation, Skoki Formation, and Road River Group (Upper Cambrian to Lower Silurian), Northeastern British Columbia. Leanne J. Pyle and Christopher R. Burnes, Canadian Journal of Earth Sciences The ''Canadian Journal of Earth Sciences'' is a monthly peer-reviewed scientific journal established in 1963, which reports current research on all aspects of the Earth sciences. It is published by NRC Research Press. The journal also publishes ..., 38(10), pages 1387–1401, 2001, External links Conodont families Proconodontida {{Conodont-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
First Appearance Datum
First appearance datum (FAD) is a term used by geologists and paleontologists to designate the first appearance of a species in the geologic record. FADs are determined by identifying the geologically oldest fossil discovered, to date, of a particular species. A related term is last appearance datum (LAD), the last appearance of a species in the geologic record. FADs are frequently used to designate segments in the geologic time scale. A given FAD can be used to define a Global Boundary Stratotype Section and Point (GSSP). For example, the beginning of the Tremadocian Stage of the Ordovician Period is marked by the first appearance of the conodont ''Iapetognathus fluctivagus'' in the geologic record. This occurs in bed 23 of the rock formation known as the Green Point section, located in western Newfoundland, as well as in geologically correlated strata in many parts of the world. However, diachronous FADs can be problematic for correlating chronostratigraphic units, particularly o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cambrian
The Cambrian Period ( ; sometimes symbolized C with bar, Ꞓ) was the first geological period of the Paleozoic Era, and of the Phanerozoic Eon. The Cambrian lasted 53.4 million years from the end of the preceding Ediacaran Period 538.8 million years ago (mya) to the beginning of the Ordovician Period mya. Its subdivisions, and its base, are somewhat in flux. The period was established as "Cambrian series" by Adam Sedgwick, who named it after Cambria, the Latin name for 'Cymru' (Wales), where Britain's Cambrian rocks are best exposed. Sedgwick identified the layer as part of his task, along with Roderick Murchison, to subdivide the large "Transition Series", although the two geologists disagreed for a while on the appropriate categorization. The Cambrian is unique in its unusually high proportion of sedimentary deposits, sites of exceptional preservation where "soft" parts of organisms are preserved as well as their more resistant shells. As a result, our understanding of the Ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ordovician
The Ordovician ( ) is a geologic period and System (geology), system, the second of six periods of the Paleozoic Era (geology), Era. The Ordovician spans 41.6 million years from the end of the Cambrian Period million years ago (Mya) to the start of the Silurian Period Mya. The Ordovician, named after the Celtic Britons, Welsh tribe of the Ordovices, was defined by Charles Lapworth in 1879 to resolve a dispute between followers of Adam Sedgwick and Roderick Murchison, who were placing the same Rock (geology), rock beds in North Wales in the Cambrian and Silurian systems, respectively. Lapworth recognized that the fossil fauna in the disputed Stratum, strata were different from those of either the Cambrian or the Silurian systems, and placed them in a system of their own. The Ordovician received international approval in 1960 (forty years after Lapworth's death), when it was adopted as an official period of the Paleozoic Era by the International Union of Geological Sciences, Intern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Green Point, Newfoundland And Labrador
Green Point is located 12 km north of the town of Rocky Harbour in Gros Morne National Park,Gros Morne National Park: Visitor information (2007) Retrieved August 18, 2008 from http://www.pc.gc.ca/pn-np/nl/grosmorne/visit/visit4_e.asp#04 on the west coast of Newfoundland. It is the home to a small summer fishing community and a drive-in campground. In 2000, Green Point was designated the Global Stratotype Section and Point (GSSP) representing the division between the Cambrian and the Ordovician systems.Cooper, R. A., Nowlan, G. S., and Williams, S. H. (2001). Global Stratotype Section and Point for Base of the Ordovician System. ''Episodes'', 24(1). Retrieved August 18, 2008, from http://www.stratigraphy.org/Tremadocian.pdf Geology In 2000, the cliffs at Green Point were approved as the Global Stratotype Section and Point for the base of the Ordovician system by the International Union of Geological Sciences. The boundary is a section 60m thick composed of layers of shale a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proconodontida Genera
Proconodontida is an order of conodonts. References * A suprageneric taxonomy of the conodonts. Maurits Lindström, Lethaia, Volume 3, Issue 4, pages 427–445, October 1970, * The conodont apparatus as a food-gathering mechanism. Maurits Lindström, palaeontology, volume17, part 4, pages 729-744 * Taxonomy, Evolution, and Biostratigraphy of Conodonts from the Kechika Formation, Skoki Formation, and Road River Group (Upper Cambrian to Lower Silurian), Northeastern British Columbia. Leanne J. Pyle and Christopher R. Burnes, Canadian Journal of Earth Sciences The ''Canadian Journal of Earth Sciences'' is a monthly peer-reviewed scientific journal established in 1963, which reports current research on all aspects of the Earth sciences. It is published by NRC Research Press. The journal also publishes ..., 38(10), pages 1387–1401, 2001, External links Prehistoric jawless fish orders {{Conodont-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossilworks
Fossilworks is a portal which provides query, download, and analysis tools to facilitate access to the Paleobiology Database The Paleobiology Database is an online resource for information on the distribution and classification of fossil animals, plants, and microorganisms. History The Paleobiology Database (PBDB) originated in the NCEAS-funded Phanerozoic Marine Pale ..., a large relational database assembled by hundreds of paleontologists from around the world. History Fossilworks was created in 1998 by John Alroy and is housed at Macquarie University. It includes many analysis and data visualization tools formerly included in the Paleobiology Database.{{cite web, title=Frequently asked questions, url=http://www.fossilworks.org/cgi-bin/bridge.pl?page=FAQ, publisher=Fossilworks, access-date=17 December 2021 References {{Reflist External links {{Wikidata property, P842 * [Baidu] |
Iapetus Ocean
The Iapetus Ocean (; ) was an ocean that existed in the late Neoproterozoic and early Paleozoic eras of the geologic timescale (between 600 and 400 million years ago). The Iapetus Ocean was situated in the southern hemisphere, between the paleocontinents of Laurentia, Baltica and Avalonia. The ocean disappeared with the Acadian, Caledonian and Taconic orogenies, when these three continents joined to form one big landmass called Euramerica. The "southern" Iapetus Ocean has been proposed to have closed with the Famatinian and Taconic orogenies, meaning a collision between Western Gondwana and Laurentia. Because the Iapetus Ocean was positioned between continental masses that would at a much later time roughly form the opposite shores of the Atlantic Ocean, it can be seen as a sort of precursor of the Atlantic, and the process by which it opened shares many similarities with that of the Atlantic's initial opening in the Jurassic. The Iapetus Ocean was therefore named for the t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Index Fossil
Biostratigraphy is the branch of stratigraphy which focuses on correlating and assigning relative ages of rock Stratum, strata by using the fossil assemblages contained within them.Hine, Robert. “Biostratigraphy.” ''Oxford Reference: Dictionary of Biology'', 8th ed., Oxford University Press, 2019. The primary objective of biostratigraphy is ''correlation'', demonstrating that a particular Horizon (geology), horizon in one geological section represents the same period of time as another horizon at a different section. Fossils within these strata are useful because sediments of the same age can look completely different, due to local variations in the Sedimentary depositional environment, sedimentary environment. For example, one section might have been made up of clays and marls, while another has more chalky limestones. However, if the fossil species recorded are similar, the two sediments are likely to have been laid down around the same time. Ideally these fossils are used to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
