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Meekoceras
''Meekoceras'' is an extinct genus of ceratitid ammonites with a discoidal shell that lived during the Early Triassic Epoch In chronology and periodization, an epoch or reference epoch is an instant in time chosen as the origin of a particular calendar era. The "epoch" serves as a reference point from which time is measured. The moment of epoch is usually decided b .... Description ''Meekoceras'' is characterized by a compressed, discoidal, evolute or involute shell with flattened sides and narrow, flattened or rounded venter that is without keels or furrows. The surface is smooth or with lateral folds, but no tubercles, spines, or spiral ridges. Umbilicus variable, body chamber short. Sutures ceratitic with smooth rounded saddles and serrated lobes. Taxonomic position Smith (1932) and Arkell et al. (1957) included ''Meekoceras'' in the Meekoceratidae, which was named to contain the genus. Different approaches were made regarding the next taxonomic level. Arkell, et al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New Mexico Museum Of Natural History And Science
The New Mexico Museum of Natural History and Science is a natural history and science museum in Albuquerque, New Mexico near Old Town Albuquerque. The Museum was founded in 1986. It operates as a public revenue facility of the New Mexico Department of Cultural Affairs. History The museum was created by an act of the New Mexico Legislature signed into law by Governor Bruce King in March, 1980. Part of the motivation for the project was to provide a home for some of the numerous dinosaur fossils discovered in New Mexico rather than sending them to out-of-state institutions. Ground was broken on a site near Old Town and the museum opened on January 11, 1986. It was one of the first new natural history museums in the U.S. in decades and represented an updated approach focusing on interactive multimedia exhibits rather than large collections of specimens displayed in glass cases. An astronomy center including an observatory and planetarium was added to the museum in 1999. This was o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early Triassic
The Early Triassic is the first of three epochs of the Triassic Period of the geologic timescale. It spans the time between 251.9 Ma and Ma (million years ago). Rocks from this epoch are collectively known as the Lower Triassic Series, which is a unit in chronostratigraphy. The Early Triassic is the oldest epoch of the Mesozoic Era. It is preceded by the Lopingian Epoch (late Permian, Paleozoic Era) and followed by the Middle Triassic Epoch. The Early Triassic is divided into the Induan and Olenekian ages. The Induan is subdivided into the Griesbachian and Dienerian subages and the Olenekian is subdivided into the Smithian and Spathian subages. The Lower Triassic series is coeval with the Scythian Stage, which is today not included in the official timescales but can be found in older literature. In Europe, most of the Lower Triassic is composed of Buntsandstein, a lithostratigraphic unit of continental red beds. The Early Triassic and partly also the Middle Trias ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triassic Ammonites
The Triassic ( ; sometimes symbolized đ) is a geologic period and system which spans 50.5 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.4 Mya. The Triassic is the first and shortest period of the Mesozoic Era and the seventh period of the Phanerozoic Eon. Both the start and end of the period are marked by major extinction events. The Triassic Period is subdivided into three epochs: Early Triassic, Middle Triassic and Late Triassic. The Triassic began in the wake of the PermianâTriassic extinction event, which left the Earth's biosphere impoverished; it was well into the middle of the Triassic before life recovered its former diversity. Three categories of organisms can be distinguished in the Triassic record: survivors from the extinction event, new groups that flourished briefly, and other new groups that went on to dominate the Mesozoic Era. Reptiles, especially archosaurs, were the chief terr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ceratitida Genera
Ceratitida is an order that contains almost all ammonoid cephalopod genera from the Triassic as well as ancestral forms from the Upper Permian, the exception being the phylloceratids which gave rise to the great diversity of post-Triassic ammonites. Ceratitids overwhelmingly produced planospirally coiled discoidal shells that may be evolute with inner whorls exposed or involute with only the outer whorl showing. In a few later forms the shell became subglobular, in others, trochoidal or uncoiled. Sutures are typically ceratitic, with smooth saddles and serrate or digitized lobes. In a few the sutures are goniatitic while in others they are ammonitic. Taxonomy * Ceratitida **Ceratitoidea ** Choristoceratoidea ** Clydonitoidea ** Danubitoidea ** Dinaritoidea ** Lobitoidea ** Meekoceratoidea ** Megaphyllitoidea ** Nathorstitoidea ** Noritoidea ** Otoceratoidea ** Pinacoceratoidea ** Ptychitoidea ** Sageceratoidea ** Tropitoidea ** Xenodiscoidea Only eight superfamilies ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonites Of North America
Ammonoids are extinct, (typically) coiled-shelled cephalopods comprising the subclass Ammonoidea. They are more closely related to living octopuses, squid, and cuttlefish (which comprise the clade Coleoidea) than they are to nautiluses (family Nautilidae). The earliest ammonoids appeared during the Emsian stage of the Early Devonian (410.62 million years ago), with the last species vanishing during or soon after the CretaceousâPaleogene extinction event (66 million years ago). They are often called ammonites, which is most frequently used for members of the order Ammonitida, the only remaining group of ammonoids from the Jurassic up until their extinction. Ammonoids exhibited considerable diversity over their evolutionary history, with over 10,000 species having been described. Ammonoids are excellent index fossils, and they have been frequently used to link rock layers in which a particular species or genus is found to specific geologic time periods. Their fossil shells usual ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prolecanitoidea
Prolecanitoidea is a taxonomic superfamily of ammonoids in the order Prolecanitida. Prolecanitoidea is one of two superfamilies in the order, along with the younger and more complex Medlicottioidea. The Prolecanitoidea were a low-diversity and morphologically conservative group. They lived from the Lower Carboniferous up to the Middle Permian. Their shells are generally smooth and discoidal, with a rounded lower edge, a moderate to large umbilicus, and goniatitic to ceratitic sutures. Suture complexity varies from 10 up to 22 total lobes (each side of a whorl combined); new lobes are added from subdivision of saddles adjacent to the original main umbilical lobe. The Prolecanitoidea encompasses two related families, the ancestral Prolecanitidae (lower Tournaisian â Bashkirian? stages) and the derived Daraelitidae (VisĂ©an â Wordian stages). Prolecanitids and daraelitids differ primarily in the complexity of the suture: Prolecanitids are simpler goniatitic forms, with round ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Treatise On Invertebrate Paleontology
The ''Treatise on Invertebrate Paleontology,'' published from 1953â2007 by the Geological Society of America and the University of Kansas, then 2009âpresent by the University of Kansas Paleontological Institute, is a definitive multi-authored work of currently 55 volumes, written by more than 300 paleontologists, and covering every phylum, class, order, family, and genus of fossil and extant (still living) invertebrate animals. The prehistoric invertebrates are described as to their taxonomy, morphology, paleoecology, stratigraphic and paleogeographic range. However, taxa with no fossil record whatsoever have just a very brief listing. Publication of the decades-long ''Treatise on Invertebrate Paleontology'' is a work-in-progress; and therefore it is not yet complete: For example, there is no volume yet published regarding the post- Paleozoic era caenogastropods (a molluscan group including the whelk and periwinkle). Furthermore, when needed, previously published vol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
James Perrin Smith
James Perrin Smith (November 27, 1864 â January 1, 1931) was an American geologist and paleontologist. Smith was of English descent. T. M. Forster, one of his ancestors, was a surgeon in the Royal Navy and moved to Virginia in 1745. His paternal grandfather moved the family from Virginia to South Carolina, and Smith was born on November 27, 1864, near Cokesburg, to James Francis Smith, a planter and traveling preacher. James P. Smith was educated by his parents and elder brother Charles Forster Smith. In the 1870s, the family moved to Spartanburg, South Carolina, where James obtained a bachelor's degree at Wofford College in 1884. Smith then attended Vanderbilt University until 1887, for a master's degree. He subsequently taught high school science and mathematics in Nashville, Tennessee for two years. Smith then worked for the Arkansas Geological Survey under John Casper Branner. Between 1890 and 1892, Smith studied at the University of Göttingen. His doctoral work was supe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epoch (geology)
The geologic time scale or geological time scale (GTS) is a representation of time based on the rock record of Earth. It is a system of chronological dating that uses chronostratigraphy (the process of relating strata to time) and geochronology (a scientific branch of geology that aims to determine the age of rocks). It is used primarily by Earth scientists (including geologists, paleontologists, geophysicists, geochemists, and paleoclimatologists) to describe the timing and relationships of events in geologic history. The time scale has been developed through the study of rock layers and the observation of their relationships and identifying features such as lithologies, paleomagnetic properties, and fossils. The definition of standardised international units of geological time is the responsibility of the International Commission on Stratigraphy (ICS), a constituent body of the International Union of Geological Sciences (IUGS), whose primary objective is to precis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
