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San Benito Formation, Bolivia
The San Benito Formation is a Katian geologic formation of central Bolivia. The formation belongs to the Cochabamba Group, overlies the Anzaldo Formation and is overlain by the Cancañiri Formation. The thick formation comprises a succession of shallow water quartzitic sandstones with minor interbeds of dark grey micaceous siltstones. Shelly fossils have been found at few horizons and consist mainly of linguliformean brachiopods, bivalves, and a few homalonotid trilobite remains. Poorly preserved graptolites occur occasionally in the shaly beds. at .org Fossil content The formation has provided the following fossils: * ''[...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] |
Graptolite
Graptolites are a group of colonial animals, members of the subclass Graptolithina within the class Pterobranchia. These filter-feeding Filter feeders are a sub-group of suspension feeding animals that feed by straining suspended matter and food particles from water, typically by passing the water over a specialized filtering structure. Some animals that use this method of feedin ... organisms are known chiefly from fossils found from the Middle Cambrian (Miaolingian, Wuliuan) through the Lower Carboniferous (Mississippian (geology), Mississippian). A possible early graptolite, ''Chaunograptus'', is known from the Middle Cambrian. Recent analyses have favored the idea that the living pterobranch ''Rhabdopleura'' represents an extant graptolite which diverged from the rest of the group in the Cambrian. Fossil graptolites and ''Rhabdopleura'' share a colony structure of interconnected zooids housed in organic tubes (theca) which have a basic structure of stacked half-rings (fuse ... [...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] |
Lingula (genus)
''Lingula'' is a genus of brachiopods within the class Lingulata. ''Lingula'' or forms very close in appearance have existed possibly since the Cambrian. Like its relatives, it has two unadorned organo-phosphatic valves and a long fleshy stalk. ''Lingula'' lives in burrows in barren sandy coastal seafloor and feeds by filtering detritus from the water. It can be detected by a short row of three openings through which it takes in water (sides) and expels it again (middle). Anatomy and morphology Shell A shell encloses the organs and other internal parts of the body, except for a long, fleshy stalk (or pedicle) that extends from the tail (or posterior) end of the shell. This shell has two nearly identical tan or bronze valves, that are often tinged greenish or bluegreenish. These are held together by muscles between them. The valves are secreted by two mantle folds, one on the dorsal and one on the ventral side of the body. The valves are composed of chitin, protein, and calci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhabdochitina
''Rhabdochitina'' is an extinct genus of chitinozoans. It was described by Alfred Eisenack in 1931. at ChitDB: Chitinozoans of Baltica. Species * ''Rhabdochitina gracilis'' Eisenack, 1962 * ''Rhabdochitina magna'' Eisenack, 1931 * ''Rhabdochitina sera'' Nestor, 2007References Prehistoric marine animals Fossil taxa described in 1931 {{Ordovician-animal-stub ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hirnantia
The Hirnantian is the final internationally recognized stage of the Ordovician Period of the Paleozoic Era. It was of short duration, lasting about 1.4 million years, from to Ma (million years ago). The early part of the Hirnantian was characterized by cold temperatures, major glaciation, and a severe drop in sea level. In the latter part of the Hirnantian, temperatures rose, the glaciers melted, and sea level returned to the same or to a slightly higher level than it had been prior to the glaciation. Most scientists believe that this climatic oscillation caused the major extinction event that took place during this time. In fact, the Hirnantian (also known as the End Ordovician and the Ordovician-Silurian) mass extinction event represents the second largest such event in geologic history. Approximately 85% of marine (sea-dwelling) species died. Only the End Permian mass extinction was larger. Unlike many smaller extinction events, however, the long-term consequences of the E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ancyrochitina
''Ancyrochitina'' is an extinct genus of chitinozoans. It was described by Alfred Eisenack in 1955. at ChitDB: Chitinozoans of Baltica. Species * ''Ancyrochitina ancyrea'' (Eisenack, 1931) * ''Ancyrochitina ansarviensis'' Laufeld, 1974 * ''Ancyrochitina bifurcaspina'' Nestor, 1994 * ''Ancyrochitina bornholmensis'' Vandenbroucke & Nõlvak, 2013 * ''Ancyrochitina brevispinosa'' Eisenack, 1968 * ''Ancyrochitina clathrospinosa'' Eisenack, 1968 * ''Ancyrochitina convexa'' Nestor, 1980 * ''Ancyrochitina diabolus'' (Eisenack, 1937) * ''Ancyrochitina digitata'' Mullins et Aldridge, 2004 * ''Ancyrochitina fragilis'' Eisenack, 1955 * ''Ancyrochitina gogginensis'' Sutherland, 1994[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
