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Nannofossils
Calcareous nannofossils are a class of tiny (less than 30 microns in diameter) microfossils that are similar to coccoliths deposited by the modern-day coccolithophores. The nannofossils are a convenient source of geochronological data due to the abundance and rapid evolution of the single-cell organisms forming them (nannoplankton) and ease of handling of the sediment samples. The practical applications of calcareous nannofossils in the areas of biostratigraphy and paleoecology became clear once the deepwater drilling took off in 1968 with the Deep Sea Drilling Project, and they have been extensively studied ever since. Nannofossils provide one of the most important paleontological records with the contiguous length of 220 million years. History of research Christian Gottfried Ehrenberg, while examining the chalk from Ruegen, recorded in 1836 an observation of what was later termed "coccolith" and had pictured the coccoliths and Discoasters in his ''Mikrogeologie'' (1854), e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coccolith
Coccoliths are individual plates or scales of calcium carbonate formed by coccolithophores (single-celled phytoplankton such as ''Emiliania huxleyi'') and cover the cell surface arranged in the form of a spherical shell, called a '' coccosphere''. Overview Coccoliths, which are about 2-25 micrometres across, enclose coccolithophores, which are spherical cells about 5-100 micrometres across. Coccolithophores are an important group of about 200 marine phytoplankton species which cover themselves with a calcium carbonate shell called a "coccosphere". They are ecologically and biogeochemically important but the reason why they calcify remains elusive. One key function may be that the coccosphere offers protection against microzooplankton predation, which is one of the main causes of phytoplankton death in the ocean. Material was copied from this source, which is available under Creative Commons Attribution 4.0 International License File:Cross section of a coccolithophore with co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coccolithophore
Coccolithophores, or coccolithophorids, are single-celled organisms which are part of the phytoplankton, the autotrophic (self-feeding) component of the plankton community. They form a group of about 200 species, and belong either to the kingdom Protista, according to Robert Whittaker (ecologist), Robert Whittaker's five-kingdom system, or clade Hacrobia, according to a newer biological classification system. Within the Hacrobia, the coccolithophores are in the phylum or division (botany), division Haptophyta, class Prymnesiophyceae (or Coccolithophyceae). Coccolithophores are almost exclusively Marine (ocean), marine, are photosynthesis, photosynthetic and mixotrophic, and exist in large numbers throughout the Photic zone, sunlight zone of the ocean. Coccolithophores are the most productive calcifying organisms on the planet, covering themselves with a calcium carbonate shell called a ''coccosphere''. However, the reasons they calcify remain elusive. One key function may be that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coccosphere
Coccolithophores, or coccolithophorids, are single-celled organisms which are part of the phytoplankton, the autotrophic (self-feeding) component of the plankton community. They form a group of about 200 species, and belong either to the kingdom Protista, according to Robert Whittaker's five-kingdom system, or clade Hacrobia, according to a newer biological classification system. Within the Hacrobia, the coccolithophores are in the phylum or division Haptophyta, class Prymnesiophyceae (or Coccolithophyceae). Coccolithophores are almost exclusively marine, are photosynthetic and mixotrophic, and exist in large numbers throughout the sunlight zone of the ocean. Coccolithophores are the most productive calcifying organisms on the planet, covering themselves with a calcium carbonate shell called a '' coccosphere''. However, the reasons they calcify remain elusive. One key function may be that the coccosphere offers protection against microzooplankton predation, which is one ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Discoaster Surculus 01
''Discoaster'' is a genus of extinct star-shaped marine algae, with calcareous exoskeletons of between 5-40 μm across that are abundant as nanofossils in tropical deep-ocean deposits of Neogene age. ''Discoaster'' belongs to the haptophytes. About 100 species can be recognized. Biostratigraphic significance The International Commission on Stratigraphy (ICS) has assigned the extinction of ''Discoaster brouweri'' as the defining biological marker for the start of the Calabrian Stage of the Pleistocene, 1.806 million years ago. ICS has assigned the extinction of ''Discoaster pentaradiatus'' and ''Discoaster surculus'' as the defining biological marker for the start of the Gelasian Stage, 2.588 million years ago, the earliest stage of the Pleistocene. ICS further assigned the extinction of ''Discoaster kugleri'' as biological marker for the start of the Tortonian Stage of the Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
George Charles Wallich
George Charles Wallich (16 November 1815 – 31 March 1899) was a British medical doctor, marine biologist and professional photographer. He was born in Calcutta where his father, the Danish naturalist Nathaniel Wallich, was Superintendent of the Royal Botanical Gardens. As a Surgeon-Major in the Indian Medical Service, he served 'during the Sutlej and Punjab campaigns, and also during the Santhal rebellion of 1855–56. He retired from the service in 1858.' In 1860 he accompanied Sir Leopold M'Clintock aboard the ''Bulldog'' on a voyage across the North Atlantic to survey the sea-bottom for the laying of the proposed trans-Atlantic cable. He won the Linnean Medal in 1898 'in recognition of the valuable work accomplished by him in connection with the exploration of the fauna of the deep sea' (''St James's Gazette'', 16 April 1898). See also * European and American voyages of scientific exploration The era of European and American voyages of scientific exploration followed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biozone
In biostratigraphy, biostratigraphic units or biozones are intervals of geological strata that are defined on the basis of their characteristic fossil taxon, taxa, as opposed to a Lithostratigraphy, lithostratigraphic unit which is defined by the Lithology, lithological properties of the surrounding rock. A biostratigraphic unit is defined by the zone fossils it contains. These may be a single taxon or combinations of taxa if the taxa are relatively abundant, or variations in features related to the distribution of fossils. The same strata may be zoned differently depending on the diagnostic criteria or fossil group chosen, so there may be several, sometimes overlapping, biostratigraphic units in the same interval. Like lithostratigraphic units, biozones must have a type section designated as a stratotype. These stratotypes are named according to the typical taxon (or taxa) that are found in that particular biozone. The boundary of two distinct biostratigraphic units is called a ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drilling Core
A core sample is a cylindrical section of (usually) a naturally-occurring substance. Most core samples are obtained by drilling with special drills into the substance, such as sediment or rock, with a hollow steel tube, called a core drill. The hole made for the core sample is called the "core hole". A variety of core samplers exist to sample different media under different conditions; there is continuing development in the technology. In the coring process, the sample is pushed more or less intact into the tube. Removed from the tube in the laboratory, it is inspected and analyzed by different techniques and equipment depending on the type of data desired. Core samples can be taken to test the properties of manmade materials, such as concrete, ceramics, some metals and alloys, especially the softer ones. Core samples can also be taken of living things, including human beings, especially of a person's bones for microscopic examination to help diagnose diseases. Methods The co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Milton Nunn Bramlette
Milton may refer to: Names * Milton (surname), a surname (and list of people with that surname) ** John Milton (1608–1674), English poet * Milton (given name) Places Australia * Milton, New South Wales * Milton, Queensland, a suburb of Brisbane ** Milton Courts, a tennis centre ** Milton House, Milton, a heritage-listed house ** Milton railway station, Brisbane ** Milton Reach, a reach of the Brisbane River ** Milton Road, an arterial road in Brisbane Canada * Milton, Newfoundland and Labrador * Milton, Nova Scotia in the Region of Queens Municipality * Milton, Ontario ** Milton line, a commuter train line ** Milton GO Station * Milton (federal electoral district), Ontario ** Milton (provincial electoral district), Ontario * Beaverton, Ontario a community in Durham Region and renamed as Beaverton in 1835 * Rural Municipality of Milton No. 292, Saskatchewan New Zealand * Milton, New Zealand United Kingdom England * Milton, Cambridgeshire, a village north of C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trygve Braarud
Trygve Braarud (15 September 1903 – 9 July 1985) was a Norwegian botanist. He specialized in marine biology, and was affiliated with the University of Oslo for most of his career. Career He was born in Verdal Municipality, and had ten older siblings as well as a twin sister. He received some of his early schooling at a private teaching institution founded by his father. He finished his secondary education at Trondheim Cathedral School in 1921, and graduated from the University of Oslo with the cand.real. degree in 1927. In his early career he published the work ''The 'Øst' Expedition to the Denmark Strait 1929'' in two volumes. The first volume, ''Hydrography'', was published together with J. T. Ruud in 1932. The second volume, ''The Phytoplankton and its Conditions of Growth'' came in 1935 and earned Braarud the dr.philos. degree. He had taken up planktology as a research assistant of Haaken Hasberg Gran at the botanical laboratory, a position he held from 1926 to 1933. From ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erwin Kamptner
Erwin may refer to: People Given name * Erwin Chargaff (1905–2002), Austrian biochemist * Erwin Chemerinsky (born 1953), American legal scholar * Erwin Dold (1919–2012), German concentration camp commandant in World War 2 * Erwin Hauer (1926–2017), Austrian-born American sculptor * Egon Erwin Kisch (1885–1948), Czechoslovak writer and journalist * Erwin Emata (born 1973), Filipino mountain climber * Erwin James (born 1957), British writer and journalist * Erwin Josi (born 1955), Swiss alpine skier * Erwin Klein (died 1992), American table tennis player * Erwin Koeman (born 1961), Dutch footballer and coach * Erwin Kramer (1902–1979), East German politician * Erwin Kreyszig (1922–2008), American academic * Erwin Neutzsky-Wulff (born 1949), Danish author and philosopher * Erwin Osen (1891–1970), Austrian painter and mime artist * Erwin Panofsky (1892-1968), German-Jewish art historian * Erwin Ramírez (born 1971), Ecuadorian football player * Erwin Rommel (1891–1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Systematics
Systematics is the study of the diversification of living forms, both past and present, and the relationships among living things through time. Relationships are visualized as evolutionary trees (synonyms: phylogenetic trees, phylogenies). Phylogenies have two components: branching order (showing group relationships, graphically represented in cladograms) and branch length (showing amount of evolution). Phylogenetic trees of species and higher taxa are used to study the evolution of traits (e.g., anatomical or molecular characteristics) and the distribution of organisms ( biogeography). Systematics, in other words, is used to understand the evolutionary history of life on Earth. The word systematics is derived from the Latin word of Ancient Greek origin '' systema,'' which means systematic arrangement of organisms. Carl Linnaeus used 'Systema Naturae' as the title of his book. Branches and applications In the study of biological systematics, researchers use the different br ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phytoplankton
Phytoplankton () are the autotrophic (self-feeding) components of the plankton community and a key part of ocean and freshwater Aquatic ecosystem, ecosystems. The name comes from the Greek language, Greek words (), meaning 'plant', and (), meaning 'wanderer' or 'drifter'. Phytoplankton obtain their energy through photosynthesis, as trees and other plants do on land. This means phytoplankton must have light from the sun, so they live in the well-lit surface layers (euphotic zone) of oceans and lakes. In comparison with terrestrial plants, phytoplankton are distributed over a larger surface area, are exposed to less seasonal variation and have markedly faster turnover rates than trees (days versus decades). As a result, phytoplankton respond rapidly on a global scale to climate variations. Phytoplankton form the base of marine and freshwater food webs and are key players in the global carbon cycle. They account for about half of global photosynthetic activity and at least half o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
