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Dengying Formation
The Dengying Formation is an upper Ediacaran (551-541 Ma) fossiliferous geologic formation found in South China. It was deposited on a shallow marine carbonate platform. Members Listed by ascending age: * The Hamajing Member is characterized by light grey, medium- to thick-bedded dolomite, intercalated with thin layers of chert. * The Shibantan Member is interpreted to represent a subtidal environment and is composed of dark grey, thin-bedded bituminous limestone. It is the most fossiliferous of the Dengying Formation members and has yielded several trace fossils, such as ''Lamonte''. * The Baimatuo Member consists of light grey, thick-bedded dolomite. Traditionally, the Tianzhushan Member was considered to be the uppermost unit of the Dengying Formation. However, its small shelly fossils and '' Micrhystridium''-like acritarchs are a shared characteristic with the Cambrian Yanjiahe Formation. Genera * '' Cloudina'' * ''Paracharnia'' * ''Sinotubulites'' * '' Yangtziramulus'' Ichn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Formation (geology)
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] |
Phosphorite Formations
Phosphorite, phosphate rock or rock phosphate is a non-detrital sedimentary rock that contains high amounts of phosphate minerals. The phosphate content of phosphorite (or grade of phosphate rock) varies greatly, from 4% to 20% phosphorus pentoxide (P2O5). Marketed phosphate rock is enriched ("beneficiated") to at least 28%, often more than 30% P2O5. This occurs through washing, screening, de-liming, magnetic separation or flotation. By comparison, the average phosphorus content of sedimentary rocks is less than 0.2%.Blatt, Harvey and Robert J. Tracy, ''Petrology'', Freeman, 1996, 2nd ed. pp. 345–349 The phosphate is present as fluorapatite Ca5(PO4)3F typically in cryptocrystalline masses (grain sizes < 1 μm) referred to as -sedimentary apatite deposits of uncertain origin. It is also present as |
Geologic Formations Of China
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 E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ediacaran Biota
The Ediacaran (; formerly Vendian) biota is a Taxonomy (biology), taxonomic period classification that consists of all life forms that were present on Earth during the Ediacaran Period (). These were composed of enigmatic tubular and frond-shaped, mostly sessility (zoology), sessile, organisms. Trace fossils of these organisms have been found worldwide, and represent the earliest known complex multicellular organisms. The Ediacaran biota may have undergone evolutionary radiation in a proposed event called the Avalon explosion, . This was after the Earth had thawed from the Cryogenian period's Snowball Earth, extensive glaciation. This biota largely disappeared with the rapid increase in biodiversity known as the Cambrian explosion. Most of the currently existing body plans of animals first appeared in the fossil, fossil record of the Cambrian rather than the Ediacaran. For macroorganisms, the Cambrian biota appears to have almost completely replaced the organisms that dominate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Fossiliferous Stratigraphic Units In China
A ''list'' is any set of items in a row. List or lists may also refer to: People * List (surname) Organizations * List College, an undergraduate division of the Jewish Theological Seminary of America * SC Germania List The SC Germania List is a German rugby union club from the district List of Hanover, currently playing in the Rugby-Bundesliga. Apart from rugby, the club also offers other sports like tennis, gymnastics and handball. The club has three German ..., German rugby union club Other uses * Angle of list, the leaning to either port or starboard of a ship * List (information), an ordered collection of pieces of information ** List (abstract data type), a method to organize data in computer science * List on Sylt, previously called List, the northernmost village in Germany, on the island of Sylt * ''List'', an alternative term for ''roll'' in flight dynamics * To ''list'' a building, etc., in the UK it means to designate it a listed building that may n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sinotubulites
''Sinotubulites'' is a genus of small, tube-shaped shelly fossils from the Ediacaran period. It is often found in association with '' Cloudina''. Its tube has a "tube-in-tube" structure composed of several thin layers. It bears prominent longitudinal sculptures and / or irregular rings, which were formed by the wrinkles of tube layers, and weaken gradually towards the inner layers. The organism probably had a sessile life-style, lying on the sea floor. ''Sinotubulites'' and ''Cloudina'' (discovered in 1972) are currently the two earliest known fossils of organisms that mineralized shells when alive, and are often found in the same fossil beds. It is remarkable that ''Cloudina'' specimens often have tiny holes bored in them, which are attributed to predators, while no such borings have been found in ''Sinotubulites''. This suggests that ''Sinotubulites'' had evolved features that made it a much less attractive target than ''Cloudina''. As a result, both organisms are important i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paracharnia
''Paracharnia'' is a reassessed genus of a fossil reported by Ding and Chen (1981). It is the first Ediacaran metazoan fossilized remains found in China, taken from the Shibantan Member, Dengying Formation, Sinian System in the Eastern Yangtze Gorge, Hubei Province. It was initially classified as ''Charnia dengyingensis'', but Sun Weiguo in 1986, comparing this to findings from Charnwood in England and the Ediacara assemblage of South Australia South Australia (commonly abbreviated as SA) is a state in the southern central part of Australia. It covers some of the most arid parts of the country. With a total land area of , it is the fourth-largest of Australia's states and territories ..., identified it as a new genera. ''Paracharnia'' is a pennatulid within the taxon of Rangeomorpha. It is closely associated with macroscopic algal remains of ''Vendotaenia'' and dense Cambrian shelly fossil deposits, suggesting its paleontological relevance. The original fossil extraction f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
