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QFL Diagram
A QFL diagram or QFL triangle is a type of ternary diagram that shows compositional data from sandstones and modern sands, point counted using the Gazzi-Dickinson method. The abbreviations used are as follows: * Q - quartz * F - feldspar * L - lithic fragments In general, the most contentious item counted is chert, which is usually counted as a lithic fragment, but is sometimes better suited in the Q pole. When this happens, the pole is renamed 'Qt' instead of Q. The importance of a QFL triangle is mainly demonstrated in tectonic exercises. As first demonstrated in the 1979 paper by Bill Dickinson and Chris Suczek, the composition and provenance of a sandstone is directly related to its tectonic environment of formation. *Craton sands are clustered near the Q pole. As sandstones, these are known as quartz arenites. *Transitional continental sands are along the QF line. As sandstones, these are known as arkoses. *Basement uplift sands are near the F pole. This include ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Christopher Anne Suczek
Christopher Anne Suczek (September 6, 1942 – April 10, 2014) was a sedimentary geologist who specialized in sedimentary petrology and plate tectonics. She received her bachelor's degree from the University of California, Berkeley in 1972 and later went on to get her PhD in Geology from Stanford University in 1977. She is best known for her contribution in determining the correlation between sedimentary deposits and plate tectonics. By the 1980s the exploration of hydrocarbons and a continuation of tectonic studies in the Pacific Northwest area of the United States led to a need of increased knowledge of the Tertiary sedimentary basins and Suczek's mapping of the area. Professor In her professional career, Suczek was a professor emeritus at Western Washington University for nearly 40 years. Some of the courses she taught were stratigraphy, sedimentation, physical and historical geography. Suczek also held a seat on the Auditing Committee for the Paleontological Society. Su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Folk Classification
The Folk classification, in geology, is a technical descriptive classification of sedimentary rocks devised by Robert L. Folk, an influential sedimentary petrologist and Professor Emeritus at the University of Texas. Folk's sandstone (clastic) classification Folk's philosophy is that the name of a rock must convey as much information as possible without being a complete description. For this, he proposed five important properties of sandstones to use as defining characteristics. These five properties are: grain size, chemically precipitated cements, textural maturity, miscellaneous transported constituents, and clan designation. Folk's fivefold name must be in the following format: :(Grain size): (chemically precipitated cements) (textural maturity) (miscellaneous transported constituents) (clan designation) However, Folk stated that cements and miscellaneous transported constituents are optional categories as they are not always observed. The other three properties should always ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanic Arc
A volcanic arc (also known as a magmatic arc) is a belt of volcanoes formed above a subducting oceanic tectonic plate, with the belt arranged in an arc shape as seen from above. Volcanic arcs typically parallel an oceanic trench, with the arc located further from the subducting plate than the trench. The oceanic plate is saturated with water, mostly in the form of hydrous minerals such as micas, amphiboles, and serpentine minerals. As the oceanic plate is subducted, it is subjected to increasing pressure and temperature with increasing depth. The heat and pressure break down the hydrous minerals in the plate, releasing water into the overlying mantle. Volatiles such as water drastically lower the melting point of the mantle, causing some of the mantle to melt and form magma at depth under the overriding plate. The magma ascends to form an arc of volcanoes parallel to the subduction zone. Volcanic arcs are distinct from volcanic chains formed over hotspots in the middle of a te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lithic Sandstone
Lithic sandstones, or lithic arenites, or litharenites, are sandstones with a significant (>5%) component of lithic fragments, though quartz and feldspar are usually present as well, along with some clayey matrix. Lithic sandstones can have a speckled (salt and pepper) or gray color, and are usually associated with one specific type of lithic fragment (i.e., igneous, sedimentary, or metamorphic).Prothero, D. R. and Schwab, F., 1996, Sedimentary Geology, pg. 100, Tectonically, lithic sandstones often form in a wide variety sedimentary depositional environments (including fluvial, deltaic, and alluvial sediments) associated with active margins. This tectonic setting provides the source of the lithic fragments, either through arc volcanism, thin-skinned faulting, continental collisions, unroofing, and subduction roll-back. See also * Arkose *Quartz arenite A quartz arenite or quartzarenite is a sandstone composed of greater than 90% detrital quartz. Quartz arenites are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orogen
An orogenic belt, or orogen, is a zone of Earth's crust affected by orogeny. An orogenic belt develops when a continental plate crumples and is Tectonic uplift, uplifted to form one or more mountain ranges; this involves a series of geological processes collectively called ''orogenesis''. Overview Orogeny typically produces ''orogenic belts'', which are elongated regions of deformation bordering continental cratons. Young orogenic belts, in which subduction is still taking place, are characterized by frequent volcanic activity and earthquakes. Older orogenic belts are typically deeply eroded to expose displaced and deformed strata. These are often highly metamorphosed and include vast bodies of intrusive igneous rock called batholiths. File:Active Margin.svg, Subduction of an oceanic plate beneath a Plate tectonics, continental plate to form an accretionary orogen. (example: the Andes) File:Continental-continental convergence Fig21contcont.gif, Continental collision of two cont ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tectonic Uplift
Tectonic uplift is the geologic uplift of Earth's surface that is attributed to plate tectonics. While isostatic response is important, an increase in the mean elevation of a region can only occur in response to tectonic processes of crustal thickening (such as mountain building events), changes in the density distribution of the crust and underlying mantle, and flexural support due to the bending of rigid lithosphere. Tectonic uplift results in denudation (processes that wear away the earth's surface) by raising buried rocks closer to the surface. This process can redistribute large loads from an elevated region to a topographically lower area as well – thus promoting an isostatic response in the region of denudation (which can cause local bedrock uplift). The timing, magnitude, and rate of denudation can be estimated by geologists using pressure-temperature studies. Crustal thickening Crustal thickening has an upward component of motion and often occurs when continental crus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arkose
Arkose () or arkosic sandstone is a detrital sedimentary rock, specifically a type of sandstone containing at least 25% feldspar. Arkosic sand is sand that is similarly rich in feldspar, and thus the potential precursor of arkose. Quartz is commonly the dominant mineral component, and some mica is often present. Apart from the mineral content, rock fragments may also be a significant component. Arkose usually contains small amounts of calcite cement, which causes it to effervesce (fizz) slightly in dilute hydrochloric acid; sometimes the cement also contains iron oxide. Arkose is typically grey to reddish in colour. The sand grains making up an arkose may range from fine to very coarse, but tend toward the coarser end of the scale. Fossils are rare in arkose, due to the depositional processes that form it, although bedding is frequently visible. Arkose is generally formed from the weathering of feldspar-rich igneous or metamorphic, most commonly granitic, rocks, which are p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quartz Arenite
A quartz arenite or quartzarenite is a sandstone composed of greater than 90% detrital quartz. Quartz arenites are the most mature sedimentary rocks possible, and are often referred to as ultra- or super-mature, and are usually cemented by silica. They often exhibit both textural and compositional maturity. The two primary sedimentary depositional environments that produce quartz arenites are beaches/upper shoreface and aeolian processes Aeolian processes, also spelled eolian, pertain to wind activity in the study of geology and weather and specifically to the wind's ability to shape the surface of the Earth (or other planets). Winds may erode, transport, and deposit materials ....Prothero, D. R. and Schwab, F., 1996, Sedimentary Geology, pg. 96-98, See also * * References Further reading * * * * * sandstone sedimentary rocks {{petrology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Craton
A craton (, , or ; from grc-gre, κράτος "strength") is an old and stable part of the continental lithosphere, which consists of Earth's two topmost layers, the crust and the uppermost mantle. Having often survived cycles of merging and rifting of continents, cratons are generally found in the interiors of tectonic plates; the exceptions occur where geologically recent rifting events have separated cratons and created passive margins along their edges. Cratons are characteristically composed of ancient crystalline basement rock, which may be covered by younger sedimentary rock. They have a thick crust and deep lithospheric roots that extend as much as several hundred kilometres into Earth's mantle. Terminology The term ''craton'' is used to distinguish the stable portion of the continental crust from regions that are more geologically active and unstable. Cratons are composed of two layers: A continental ''shield'', in which the basement rock crops out at the surface ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Provenance
Provenance (from the French ''provenir'', 'to come from/forth') is the chronology of the ownership, custody or location of a historical object. The term was originally mostly used in relation to works of art but is now used in similar senses in a wide range of fields, including archaeology, paleontology, archives, manuscripts, printed books, the circular economy, and science and computing. The primary purpose of tracing the provenance of an object or entity is normally to provide contextual and circumstantial evidence for its original production or discovery, by establishing, as far as practicable, its later history, especially the sequences of its formal ownership, custody and places of storage. The practice has a particular value in helping Authentication, authenticate objects. Comparative techniques, expert opinions and the results of scientific tests may also be used to these ends, but establishing provenance is essentially a matter of documentation. The term dates to the 1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William R
William is a male given name of Germanic origin.Hanks, Hardcastle and Hodges, ''Oxford Dictionary of First Names'', Oxford University Press, 2nd edition, , p. 276. It became very popular in the English language after the Norman conquest of England in 1066,All Things William"Meaning & Origin of the Name"/ref> and remained so throughout the Middle Ages and into the modern era. It is sometimes abbreviated "Wm." Shortened familiar versions in English include Will, Wills, Willy, Willie, Bill, and Billy. A common Irish form is Liam. Scottish diminutives include Wull, Willie or Wullie (as in Oor Wullie or the play ''Douglas''). Female forms are Willa, Willemina, Wilma and Wilhelmina. Etymology William is related to the given name ''Wilhelm'' (cf. Proto-Germanic ᚹᛁᛚᛃᚨᚺᛖᛚᛗᚨᛉ, ''*Wiljahelmaz'' > German ''Wilhelm'' and Old Norse ᚢᛁᛚᛋᛅᚼᛅᛚᛘᛅᛋ, ''Vilhjálmr''). By regular sound changes, the native, inherited English form of the name shoul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
