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Arauz Formation
The Arauz Formation is an Emsian fossiliferous stratigraphic unit in Spain.Arauz Formation in the Paleobiology Database It is a member of the Abadia Group. It is situated in the Province of Palencia, North Spain. It is in the north of Natural Park of Fuentes Carrionas and Fuente Cobre-Montaña Palentina where the Rio Arauz lies. It is from the Devonian of Spain.Silur und Devon im Arauz-Gebiet (Prov. Palencia, N-Spanien). H. Jahnke, A. Henn, H. Mader and J. Schweineberg, 1983, Newsletters on Stratigraphy, 13(1), pages 40-66, Fossil content The following fossils have been reported from the formation: * Trilobites ** ''Kayserops, Kayserops obsoletus'' ** ''Metacanthina, Metacanthina cf. asnoensis'' ** ''Leonaspis, Leonaspis sp.'' ** ''Metacanthina, ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geological Formation
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] |
Pleurodictyum
''Pleurodictyum'' is an extinct genus of tabulate corals, characterized by polygonal corallites. Colonies commonly encrust hard substrates such as rocks, shells and carbonate hardgrounds. Distribution Fossils of ''Pleurodictyum'' have been found in:''Pleurodictyum'' at .org ;Silurian Argentina, Australia, Bolivia, Tajikistan, and the United States (Kentucky, Wisconsin) ;Devonian Algeria, Australia, Bolivia, Brazil, Canada (Ontario), China, Colombia (, |
Coral
Corals are marine invertebrates within the class Anthozoa of the phylum Cnidaria. They typically form compact colonies of many identical individual polyps. Coral species include the important reef builders that inhabit tropical oceans and secrete calcium carbonate to form a hard skeleton. A coral "group" is a colony of very many genetically identical polyps. Each polyp is a sac-like animal typically only a few millimeters in diameter and a few centimeters in height. A set of tentacles surround a central mouth opening. Each polyp excretes an exoskeleton near the base. Over many generations, the colony thus creates a skeleton characteristic of the species which can measure up to several meters in size. Individual colonies grow by asexual reproduction of polyps. Corals also breed sexually by spawning: polyps of the same species release gametes simultaneously overnight, often around a full moon. Fertilized eggs form planulae, a mobile early form of the coral polyp which, when m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mimagoniatites
''Mimagoniatites'' is a genus of ammonoid cephalopod which lived during the early Devonian The Devonian ( ) is a geologic period and system of the Paleozoic era, spanning 60.3 million years from the end of the Silurian, million years ago (Mya), to the beginning of the Carboniferous, Mya. It is named after Devon, England, whe ..., regarded as belonging to the Agoniatitdae as a member of the subfamily Mimagoniatitinae. The shell is discoidal, primarily evolute, becoming mildly involute in later growth stage, moderately to rapidly expanding. Whorl section of first two whorls approximately circular, subtrapezoidal in later whorls. Umbilicas perforated, protoconch swollen, not in contact with first whorl. Growth lines biconvex with prominent ventrolateral projections and a deep ventral sinus. References *''Mimagoniatites'' iGONIATonline''Mimagoniatites'' Paleobio db. *Miller, Furnish, and Schindewolf, 1957. Paleozoic Ammonoidea; Treatise on Invertebrate Paleontolo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
