|
San Lorenzo Formation, Bolivia
The San Lorenzo Formation is a Dapingian geologic formation of southern Bolivia. The dark gray, greenish, and black shale with thin intercalations of white-yellow quartzites were deposited in an open marine submarine fan environment. at .org Fossil content The formation has provided the following fossils: * '' Didymograptus nitidus'' * '' Dinorthis obispoensis'' * '' Orthamboni ...[...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] |
Tetragraptus
''Tetragraptus'' is an extinct genus of graptolites from the Ordovician period. Species * ''T. akzharensis'' * '' T. approximatus'' * '' T. fruticosus'' * ''T. insuetus'' Distribution Fossils of ''Tetragraptus'' have been found in Argentina, Australia, Bolivia, Canada (Quebec, Yukon, Newfoundland and Labrador and Northwest Territories), Chile, China, Colombia (near Caño Cristales, Meta), the Czech Republic, France, Morocco, New Zealand, Norway, the Russian Federation, Spain, Sweden, the United Kingdom, and the United States (Alaska, Idaho, Nevada, Utah).''Tetragraptus'' at Fossilworks
Fossilworks is a portal which provides query, download, and analysis tool ...
[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shale Formations
Shale is a fine-grained, clastic sedimentary rock formed from mud that is a mix of flakes of clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4) and tiny fragments (silt-sized particles) of other minerals, especially quartz and calcite.Blatt, Harvey and Robert J. Tracy (1996) ''Petrology: Igneous, Sedimentary and Metamorphic'', 2nd ed., Freeman, pp. 281–292 Shale is characterized by its tendency to split into thin layers ( laminae) less than one centimeter in thickness. This property is called '' fissility''. Shale is the most common sedimentary rock. The term ''shale'' is sometimes applied more broadly, as essentially a synonym for mudrock, rather than in the more narrow sense of clay-rich fissile mudrock. Texture Shale typically exhibits varying degrees of fissility. Because of the parallel orientation of clay mineral flakes in shale, it breaks into thin layers, often splintery and usually parallel to the otherwise indistinguishable bedding ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ordovician Bolivia
The Ordovician ( ) is a geologic period and system, the second of six periods of the Paleozoic 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 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 beds in North Wales in the Cambrian and Silurian systems, respectively. Lapworth recognized that the fossil fauna in the disputed 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 Geological Congress. Life continued to flourish during the Ordovician as it did in the earlier Cambrian Perio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ordovician System Of South America
The Ordovician ( ) is a geologic period and system, the second of six periods of the Paleozoic 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 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 beds in North Wales in the Cambrian and Silurian systems, respectively. Lapworth recognized that the fossil fauna in the disputed 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 Geological Congress. Life continued to flourish during the Ordovician as it did in the earlier Cambrian Per ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geologic Formations Of Bolivia
Geology () is a branch of natural science concerned with Earth and other astronomical objects, the features or rocks of which it is composed, and the processes by which they change over time. Modern geology significantly overlaps all other Earth sciences, including hydrology, and so is treated as one major aspect of integrated Earth system science and planetary science. Geology describes the structure of the Earth on and beneath its surface, and the processes that have shaped that structure. It also provides tools to determine the relative and absolute ages of rocks found in a given location, and also to describe the histories of those rocks. By combining these tools, geologists are able to chronicle the geological history of the Earth as a whole, and also to demonstrate the age of the Earth. Geology provides the primary evidence for plate tectonics, the evolutionary history of life, and the Earth's past climates. Geologists broadly study the properties and processes of Ea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Fossiliferous Stratigraphic Units In Bolivia
This is a list of fossiliferous stratigraphic units in Bolivia. __NOTOC__ List of fossiliferous stratigraphic units See also * * Gomphothere fossils in Bolivia * South American land mammal ages * List of fossiliferous stratigraphic units in Paraguay * List of fossiliferous stratigraphic units in Peru References Bibliography * * ;Cajones Formation * ;Casira Formation * ;Cerdas beds * ;Honda Group * * * * ;Lacayani fauna * ;Mesón Group * ;Los Monos Formation * ;Ñuapua Formation * ;La Puerta Formation * ;Puncoviscana Formation * ;Quehua Formation * ;Salla Formation * * * ;Santa Lucía Formation * * * * * * * * * ;Tarija Formation * ;Toro Toro Formation * * ;Umala Formation * ;Yecua & Petaca Formations * Further reading * ;Mesozoic * L. Branisa. 1968. Hallazgo del amonite Neolobites en la Caliza Miraflores y de huellas de dinosaurios en la formación El Molino y su significado para la determinación de la ed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megalaspidella
''Megalaspidella'' is an extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ... genus from a well-known class of fossil marine arthropods, the trilobites. It lived during the later part of the Arenig stage of the Ordovician Period, approximately 478 to 471 million years ago. References Asaphida genera Asaphidae Ordovician trilobites of Asia Fossils of China Ordovician trilobites of Europe Fossils of France Ordovician trilobites of North America Fossils of the United States Ordovician trilobites of South America Fossils of Argentina Fossils of Bolivia Fossil taxa described in 1937 {{asaphida-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endoceras
''Endoceras'' ( Ancient Greek for "inner horn") is an extinct genus of large, straight shelled cephalopods from the Middle and Upper Ordovician that gives its name to the Nautiloid order Endocerida. The cross section in the mature portion is slightly wider than high, but is narrower laterally in the young. Sutures are straight and transverse. ''Endoceras'' has a large siphuncle, located close to the ventral margin, composed of concave segments, especially in the young but which may be tubular in the adult stage. Endocones are simple, subcircular in cross section, and penetrated by a narrow tube which may contain diaphragms reminiscent of the Ellesmerocerid ancestor. ''Endoceras'' was named by Hall in 1847. Distribution is widespread, especially in North America and Europe; and fossils have been found in Australia. ''Endoceras'' is similar to '' Cameroceras'', the two may be synonymous, but differs from the genus ''Nanno Nanno (german: Nain, Ladin: ''Nan'') was a '' comune'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dictyonema (graptolite)
''Dictyonema'' is a genus of dendroid graptolithina, graptolites in the order Dendroidea. Fossil record Fossils of ''Dictyonema'' are found from the Upper Cambrian to the Devonian (age range: from 488.3 to 383.7 million years ago.). They are known from various localities in Europe, North America, South America, China and Morocco. Description These colonial organism are characterized by a conical, net-like structure. The colonies (known as rhabdosomes) are branched and may vary from almost discoidal to almost cylindrical. They were stationary planktonic suspension feeders. Species *†''Dictyonema macgillivrayi'' (Hall 1899) *†''Dictyonema pulchellum'' (Hall 1899) *†''Dictyonema retiforme'' (Hall 1843) Bibliography *Bulman, O. M. B. 1970. Graptolithina with sections of Enteropneusta and Pterobranchia. In Treatise on Invertebrate Paleontology Part V 2nd ed. (C. Teichert, ed.) pp. V1-V149. The Geological Society of America, Inc.: Boulder (Colorado), and the University of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
