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Palynomorph
Palynology is the study of microorganisms and microscopic fragments of mega-organisms that are composed of acid-resistant organic material and occur in sediments, sedimentary rocks, and even some metasedimentary rocks. Palynomorphs are the microscopic, acid-resistant organic remains and debris produced by a wide variety of plants, animals, and Protista that have existed since the late Proterozoic.Neuendorf, K.K.E., J.P. Mehl, Jr., and J.A. Jackson, eds., 2005, ''Glossary of Geology'' (5th ed.). Alexandria, Virginia, American Geological Institute. 779 pp. It is the science that studies contemporary and fossil palynomorphs (paleopalynology), including pollen, spores, orbicules, dinocysts, acritarchs, chitinozoans and scolecodonts, together with particulate organic matter (POM) and kerogen found in sedimentary rocks and sediments. Palynology does not include diatoms, foraminiferans or other organisms with siliceous or calcareous tests. The name of the science and organisms is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dinocysts
Dinocysts or dinoflagellate cysts are typically 15 to 100 μm in diameter and produced by dinoflagellates as a dormant, zygotic stage of their lifecycle, which can accumulate in the sediments as microfossils. Organic-walled dinocysts are often resistant and made out of dinosporin. There are also calcareous dinoflagellate cysts and siliceous dinoflagellate cysts. History The first person to recognize fossil dinoflagellates was Christian Gottfried Ehrenberg, who reported his discovery in a paper presented to the Berlin Academy of Sciences in July 1836. He had observed clearly tabulate dinoflagellates in thin flakes of Cretaceous flint and considered those dinoflagellates to have been silicified. Along with them, and of comparable size, were spheroidal to ovoidal bodies bearing an array of spines or tubes of variable character. Ehrenberg interpreted these as being originally siliceous and thought them to be desmids (freshwater conjugating algae), placing them within his ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acritarchs
Acritarchs () are organic microfossils, known from the Precambrian to the present. The classification is a catch all term used to refer to any organic microfossils that cannot be assigned to other groups. Their diversity reflects major ecological events such as the appearance of predation and the Cambrian explosion. Many acritarchs likely represent resting cysts of single-celled marine phytoplanktonic algae, similar to those produced by living dinoflagellates. Definition Acritarchs were originally defined as non-acid soluble (i.e. non-carbonate, non- siliceous) organic-walled microfossils consisting of a central cavity, and whose biological affinities cannot be determined with certainty. Most commonly they are composed of thermally altered acid insoluble carbon compounds (kerogen). Acritarchs may include the remains of a wide range of quite different kinds of organisms—ranging from the egg cases of small metazoans to resting cysts of many kinds of chlorophyta (green algae) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
-logy
''-logy'' is a suffix in the English language, used with words originally adapted from Ancient Greek ending in ('). The earliest English examples were anglicizations of the French '' -logie'', which was in turn inherited from the Latin '' -logia''. The suffix became productive in English from the 18th century, allowing the formation of new terms with no Latin or Greek precedent. The English suffix has two separate main senses, reflecting two sources of the suffix in Greek: *a combining form used in the names of school or bodies of knowledge, e.g., ''theology'' (loaned from Latin in the 14th century) or ''sociology''. In words of the type ''theology'', the suffix is derived originally from (''-log-'') (a variant of , ''-leg-''), from the Greek verb (''legein'', 'to speak')."-logy." ''The Concise Oxford Dictionary of English Etymology''. Oxford University Press, 1986. retrieved 20 August 2008. The suffix has the sense of "the character or deportment of one who speaks or tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Foraminiferans
Foraminifera ( ; Latin for "hole bearers"; informally called "forams") are single-celled organisms, members of a phylum or class of Rhizarian protists characterized by streaming granular ectoplasm for catching food and other uses; and commonly an external shell (called a "test") of diverse forms and materials. Tests of chitin (found in some simple genera, and '' Textularia'' in particular) are believed to be the most primitive type. Most foraminifera are marine, the majority of which live on or within the seafloor sediment (i.e., are benthic, with different sized species playing a role within the macrobenthos, meiobenthos, and microbenthos), while a smaller number float in the water column at various depths (i.e., are planktonic), which belong to the suborder Globigerinina. Fewer are known from freshwater or brackish conditions, and some very few (nonaquatic) soil species have been identified through molecular analysis of small subunit ribosomal DNA. Foraminifera typically pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siliceous
Silicon dioxide, also known as silica, is an oxide of silicon with the chemical formula , commonly found in nature as quartz. In many parts of the world, silica is the major constituent of sand. Silica is one of the most complex and abundant families of materials, existing as a compound of several minerals and as a synthetic product. Examples include fused quartz, fumed silica, opal, and aerogels. It is used in structural materials, microelectronics, and as components in the food and pharmaceutical industries. All forms are white or colorless, although impure samples can be colored. Silicon dioxide is a common fundamental constituent of glass. Structure In the majority of silicon dioxides, the silicon atom shows tetrahedral coordination, with four oxygen atoms surrounding a central Si atomsee 3-D Unit Cell. Thus, SiO2 forms 3-dimensional network solids in which each silicon atom is covalently bonded in a tetrahedral manner to 4 oxygen atoms. In contrast, CO2 is a linear ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcareous
Calcareous () is an adjective meaning "mostly or partly composed of calcium carbonate", in other words, containing lime (mineral), lime or being chalky. The term is used in a wide variety of Science, scientific disciplines. In zoology ''Calcareous'' is used as an adjectival term applied to anatomical structures which are made primarily of calcium carbonate, in animals such as gastropods, i.e., snails, specifically in relation to such structures as the operculum (gastropod), operculum, the clausilium, and the love dart. The term also applies to the calcium carbonate Test (biology), tests of, often, more-or-less microscopic Foraminifera. Not all tests are calcareous; diatoms and radiolaria have siliceous tests. The molluscs are calcareous organisms, as are the Calcarea, calcareous sponges (Calcarea), that have spicules which are made of calcium carbonate. Additionally, reef-building corals, or Scleractinia, are calcareous organisms that form their rigid skeletal structure th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Test (biology)
In biology, a test is the hard Seashell, shell of some spherical aquatic animals and protists, notably sea urchins and microorganisms such as testate foraminiferans, radiolarians, and testate amoebae. The term is also applied to the covering of scale insects. The related Latin term testa (botany), testa is used for the outer layer of the hard seed coat of plant seeds. Etymology The anatomical term "test" derives from the Latin word ''wikt:testa#Latin, testa'', which refers to an earthenware object, for example, a piece of pottery, a tile, or a potshard, and by extension, the mollusc shell, shell of a mollusc or a skull. Structure The test is a skeletal structure, made of hard material such as calcium carbonate, silica, chitin or composite materials. As such, it allows the protection of the internal organs and the attachment of soft flesh. The structure is notable for its Ambulacral, ambulacra, alternating in wide and narrow patterns. Small serrations, bumps, ridges or th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sedimentary
Sedimentary rocks are types of rock formed by the cementation of sediments—i.e. particles made of minerals (geological detritus) or organic matter (biological detritus)—that have been accumulated or deposited at Earth's surface. Sedimentation is any process that causes these particles to settle in place. Geological detritus originates from weathering and erosion of existing rocks, or from the solidification of molten lava blobs erupted by volcanoes. The geological detritus is transported to the place of deposition by water, wind, ice or mass movement, which are called agents of denudation. Biological detritus is formed by bodies and parts (mainly shells) of dead aquatic organisms, as well as their fecal mass, suspended in water and slowly piling up on the floor of water bodies ( marine snow). Sedimentation may also occur when dissolved minerals precipitate from water solution. The sedimentary rock cover of the continents of the Earth's crust is extensive (73% of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earth Science
Earth science or geoscience includes all fields of natural science related to the planet Earth. This is a branch of science dealing with the physical, chemical, and biological complex constitutions and synergistic linkages of Earth's four spheres: the biosphere, hydrosphere/ cryosphere, atmosphere, and geosphere (or lithosphere). Earth science can be considered to be a branch of planetary science but with a much older history. Geology Geology is broadly the study of Earth's structure, substance, and processes. Geology is largely the study of the lithosphere, or Earth's surface, including the crust and rocks. It includes the physical characteristics and processes that occur in the lithosphere as well as how they are affected by geothermal energy. It incorporates aspects of chemistry, physics, and biology as elements of geology interact. Historical geology is the application of geology to interpret Earth history and how it has changed over time. Geochemistry studies the che ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geology
Geology (). is a branch of natural science concerned with the Earth and other astronomical objects, the rocks of which they are composed, and the processes by which they change over time. Modern geology significantly overlaps all other Earth sciences, including hydrology. It is integrated with 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. Geologists study the mineralogical composition of rocks in order to get insight into their history of formation. Geology determines the relative ages of rocks found at a given location; geochemistry (a branch of geology) determines their absolute ages. By combining various petrological, crystallographic, and paleontological tools, geologists are able to chronicle the geological history of the Earth as a whole. One aspect is to demonstrate the age of the Earth. Geology provides evidence for plate tectonics, the ev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
