Subject:
All Disciplines Arts & Humanities Biology & Life Sciences Business & Economics Chemistry & Materials Science Computer Science & Mathematics Engineering Environmental & Earth Sciences Medicine & Pharmacology Physical Sciences Public Health & Healthcare Social Sciences
Sort:
Most Viewed Latest Alphabetical (A-Z) Alphabetical (Z-A)
Filter:
All Topic Review Biography Peer Reviewed Entry Video Entry
Topic Review
List of Minerals Approved by IMA (F)
This list includes those recognised minerals beginning with the letter F. The International Mineralogical Association is the international group that recognises new minerals and new mineral names, however minerals discovered before 1959 did not go through the official naming procedure, although some minerals published previously have been either confirmed or discredited since that date. This list contains a mixture of mineral names that have been approved since 1959 and those mineral names believed to still refer to valid mineral species (these are called "grandfathered" species). The list is divided into groups: The data was exported from mindat.org on 29 April 2005; updated up to 'IMA2018'. The minerals are sorted by name, followed by the structural group (rruff.info/ima and ima-cnmnc by mineralienatlas.de, mainly) or chemical class (mindat.org and basics), the year of publication (if it's before of an IMA approval procedure), the IMA approval and the Nickel–Strunz code. The first link is to mindat.org, the second link is to webmineral.com, and the third is to the Handbook of Mineralogy (Mineralogical Society of America).
  • 572
  • 07 Nov 2022
Topic Review
Soil in Dogu'a Tembien
The soils of the Dogu’a Tembien woreda (district) in Tigray (Ethiopia) reflect its longstanding agricultural history, highly seasonal rainfall regime, relatively low temperatures, an extremely great variety in lithology (with dominance of basalts and limestone) and steep slopes. Outstanding features in the soilscape are the fertile highland Vertisols and Phaeozems in forests.
  • 570
  • 23 Nov 2022
Topic Review
River Anticlines
A river anticline is a geologic structure that is formed by the focused uplift of rock caused by high erosion rates from large rivers relative to the surrounding areas. An anticline is a fold that is concave down, whose limbs are dipping away from its axis, and whose oldest units are in the middle of the fold. These features form in a number of structural settings. In the case of river anticlines, they form due to high erosion rates, usually in orogenic settings. In a mountain building setting, like that of the Himalaya or the Andes, erosion rates are high and the river anticline's fold axis will trend parallel to a major river. When river anticlines form, they have a zone of uplift between 50-80 kilometers wide along the rivers that form them.
  • 553
  • 01 Dec 2022
Topic Review
Hillslope Hydrology and Stability in Taiwan
Owing to active orogenic movement and the monsoon climate, rainfall-induced landslide disasters often occur in Taiwan. Hence, hillslope hydrology and stability have received considerable research attention. However, it remains difficult to accurately estimate the duration and consequences of hillslope instability induced by hillslope hydrology. Research on hillslope hydrology and stability is complicated by spatial heterogeneity, hydrological processes operating at various scales, spatiotemporal evolution, and geomorphological properties. Recent advances in critical zone science have provided an approach to extend geoscience studies. The “deep coupling” concept is essential for integrating physical, chemical, and biological processes on various spatiotemporal scales and for providing a macro and unified framework for evaluating internal properties and processes.
  • 541
  • 18 Dec 2023
Topic Review
Remote Sensing of Geomorphodiversity Linked to Biodiversity
Remote sensing (RS) enables a cost-effective, extensive, continuous and standardized monitoring of traits and trait variations of geomorphology and its processes, from the local to the continental scale. RS technologies can record geomorphic traits, their diversity and variations, from which the other four geomorphodiversity characteristics are derived. However, compared to in situ measurements, RS approaches can only record certain parts of these geomorphic traits and their variations. This is because capturing geomorphic traits and diversity using RS approaches is limited by various constraints, namely: (1) the characteristics and spatial-temporal distribution of geomorphic traits; (2) the characteristics of geomorphological processes; as well as (3) the RS sensor characteristics, the chosen RS platforms and the characteristics of RS data-processing and classification information. These constraints and limitations define the detectability, feasibility, accuracy, depth of information, repeatability, and, thus, standards disability in monitoring the five geomorphic characteristics using RS approaches.
  • 529
  • 20 May 2022
Topic Review
Exmoor Group
The Exmoor Group is a late Devonian to early Carboniferous lithostratigraphic group (a sequence of rock strata) in southwest England whose outcrop extends from Croyde in north Devon east across Exmoor to Minehead in west Somerset. Each of these divisions has been given different names by different authors in the past including those shown in brackets above. Some that had been classed as 'formations' (or even in one case as a 'group') are now 'members'.
  • 478
  • 16 Nov 2022
Topic Review
Seismic Array
A seismic array is a system of linked seismometers arranged in a regular geometric pattern (cross, circle, rectangular etc.) to increase sensitivity to earthquake and explosion detection. A seismic array differs from a local network of seismic stations mainly by the techniques used for data analysis. The data from a seismic array is obtained using special digital signal processing techniques such as beamforming, which suppress noises and thus enhance the signal-to-noise ratio (SNR). The earliest seismic arrays were built in the 1950s in order to improve the detection of nuclear tests worldwide. Many of these deployed arrays were classified until the 1990s. Today they become part of the IMS as primary or auxiliary stations. Seismic arrays are not only used to monitor earthquakes and nuclear tests, but also used as a tool for investigating nature and source regions of microseisms as well as locating and tracking volcanic tremor and analyzing complex seismic wave-field properties in volcanic areas.
  • 474
  • 29 Sep 2022
Topic Review
Coal Assay
Coal analysis techniques are specific analytical methods designed to measure the particular physical and chemical properties of coals. These methods are used primarily to determine the suitability of coal for coking, power generation or for iron ore smelting in the manufacture of steel.
  • 461
  • 24 Oct 2022
Topic Review
Fracture Characterization of Naturally Fractured Reservoirs
Recent developments in fracture characterization, modeling, and the impact of fracture networks on oil recovery in naturally carbonate-fractured reservoirs have been reviewed. The pivotal role of fracture identification and characterization in understanding production mechanisms and developing realistic fracture modeling approaches has been highlighted. This concludes that improved fracture network modeling requires considering various factors, such as data collection, fracture characterization, reservoir simulation, and model updating based on newly acquired field data. Integrating multiple techniques and data sources is recommended for obtaining a reliable reservoir model to optimize primary and enhanced oil recovery methods.
  • 456
  • 08 May 2023
Topic Review
Bagua Basin, Peru
Located in northern Peru, at the lowest segment of the Central Andes, the Bagua Basin contains a Campanian to Pleistocene sedimentary record that archives the local paleoenvironmental and tectonic history.  
  • 447
  • 28 Jun 2022
Topic Review
Izu-Bonin-Mariana Arc
The Izu-Bonin-Mariana (IBM) arc system is a tectonic-plate convergent boundary. The IBM arc system extends over 2800 km south from Tokyo, Japan , to beyond Guam, and includes the Izu Islands, Bonin Islands, and Mariana Islands; much more of the IBM arc system is submerged below sealevel. The IBM arc system lies along the eastern margin of the Philippine Sea Plate in the Western Pacific Ocean. It is most famous for being the site of the deepest gash in Earth's solid surface, the Challenger Deep in the Mariana Trench. The IBM arc system formed as a result of subduction of the western Pacific plate. The IBM arc system now subducts mid-Jurassic to Early Cretaceous lithosphere, with younger lithosphere in the north and older lithosphere in the south, including the oldest (~170 million years old, or Ma) oceanic crust. Subduction rates vary from ~2 cm (1 inch) per year in the south to 6 cm (~2.5 inches) in the north. The volcanic islands that comprise these island arcs are thought to have been formed from the release of volatiles (steam from trapped water, and other gases) being released from the subducted plate, as it reached sufficient depth for the temperature to cause release of these materials. The associated trenches are formed as the oldest (most western) part of the Pacific plate crust increases in density with age, and because of this process finally reaches its lowest point just as it subducts under the crust to the west of it. The IBM arc system is an excellent example of an intra-oceanic convergent margin (IOCM). IOCMs are built on oceanic crust and contrast fundamentally with island arc built on continental crust, such as Japan or the Andes. Because IOCM crust is thinner, denser, and more refractory than that beneath Andean-type margins, study of IOCM melts and fluids allows more confident assessment of mantle-to-crust fluxes and processes than is possible for Andean-type convergent margins. Because IOCMs are far removed from continents they are not affected by the large volume of alluvial and glacial sediments. The consequent thin sedimentary cover makes it much easier to study arc infrastructure and determine the mass and composition of subducted sediments. Active hydrothermal systems found on the submarine parts of IOCMs give us a chance to study how many of earth's important ore deposits formed.
  • 434
  • 04 Nov 2022
Topic Review
Driving Factors of Ecosystem Services
The optimization of tree structure contributes to the improvement in Ecosystem service (ES) provision and the regulation capacity. Species diversity plays an important role in provision services, while functional diversity is equally important in regulation services. Plant root functional traits can not only help regulation services but also determine the species and structure of rhizosphere microbial communities. The response of ES to a certain factor has been extensively reviewed, but the interaction of multiple driving factors needs to be further studied, especially in how to drive the supply capacity of ES in multi-factor and multi-scale ways. Clarifying the driving mechanism of ES at different scales will help to improve the supply capacity of the ecosystem and achieve the goal of sustainable development.
  • 417
  • 21 Apr 2023
Topic Review
Soil in Kilte Awula'ilo
The soils of the Kilte Awula’ilo woreda (district) in Tigray reflect its longstanding agricultural history, highly seasonal rainfall regime, relatively low temperatures, the presence of a wide depression at the foot of the Atsbi horst and steep slopes. Outstanding features in the soilscape are the wide ancient fluvial deposits, the soils of the granite batholith, cuestas and fertile lands behind tufa dams.
  • 412
  • 07 Nov 2022
Topic Review
Tollmann's Hypothetical Bolide
Alexander Tollmann's bolide, proposed by Kristan-Tollmann and Tollmann in 1994, is a hypothesis presented by Austrian geologist Alexander Tollmann, suggesting that one or several bolides (asteroids or comets) struck the Earth at 7640 BCE (±200), with a much smaller one at 3150 BCE (±200). If true, this hypothesis explains early Holocene extinctions and possibly legends of the Universal Deluge. The claimed evidence for the event includes stratigraphic studies of tektites, dendrochronology, and ice cores (from Camp Century, Greenland) containing hydrochloric acid and sulfuric acid (indicating an energetic ocean strike) as well as nitric acids (caused by extreme heating of air). Christopher Knight and Robert Lomas in their book, Uriel's Machine, argue that the 7640 BCE evidence is consistent with the dates of formation of a number of extant salt flats and lakes in dry areas of North America and Asia. They argue that these lakes are the result remains of multiple-kilometer-high waves that penetrated deeply into continents as the result of oceanic strikes that they proposed occurred.
  • 412
  • 08 Nov 2022
Topic Review
The UNESCO Site of the Chaîne des Puys
The tectono-volcanic ensemble of the Chaîne des Puys and the Limagne fault, which is part of the West European rift, was inscribed on the UNESCO World Heritage list in 2018 as the Chaîne des Puys–Limagne fault tectonic arena.
  • 407
  • 25 Sep 2023
Topic Review
Carbonate Reservoirs Permeability Prediction
Permeability is a crucial property that can be used to indicate whether a material can hold fluids or not. Predicting the permeability of carbonate reservoirs is always a challenging and expensive task while using traditional techniques. Traditional methods often demand a significant amount of time, resources, and manpower, which are sometimes beyond the limitations of under developing countries.
  • 407
  • 10 Oct 2023
Topic Review
Numerical Simulation Methods in Shale Oil Flow
The pore structure of shale oil reservoirs is complex, and the microscale and nanoscale effect is obvious in the development of shale oil reservoirs. Understanding the oil flow mechanism in shale reservoirs is essential for optimizing the development plan and enhancing the recovery rate of shale oil reservoirs.
  • 400
  • 10 May 2023
Topic Review
Shoal-to-Strata Ratio Technique
The requirements for the accurate characterization of shoal sediments have increased in view of the fact that strata are eroded due to uplift and it is difficult to calculate the real thickness of granular shoal. To solve this problem, with the shoal-to-strata ratio, the type and distribution range of carbonate rock shoal facies are described, and the characterization of sedimentary facies is subsequently presented.
  • 398
  • 01 Jul 2022
Topic Review
Regional Geological of the Biga Peninsula
Biga Peninsula is a geologically diverse and complex peninsula that has been exposed to a series of tectonic events during its lengthy history. It represents the western section of the Sakarya Zone (S Pontide Domain) along the boundary between Gondwana and Laurasia and consists of numerous tectonic units, representing both continental and oceanic assemblages. The tectonic activity of the Biga Peninsula is primarily impacted by the motion occurring along the North Anatolian Fault Zone.
  • 389
  • 23 Oct 2023
Topic Review
Geological Site Effects in Archaeoseismological Point of View
Earthquakes have and continue to, occur worldwide, though some places are affected more than others by earthquake-induced ground shaking and the same earthquake can cause more damage in one area than in nearby locations due to site-specific geological site conditions, also known as local site effects. Depending on the chronology of the earthquakes, various disciplines of seismology include instrumental and historical seismology, archaeoseismology, palaeoseismology and neotectonics, each focusing on using specific sources of information to evaluate recent or ancient earthquakes. Past earthquakes are investigated to expand the pre-instrumental and instrumental earthquake catalog and better evaluate a region’s seismic hazard. Archaeoseismology offers a way to achieve these goals because it links how ancient civilizations and their environment might have interacted and responded to past earthquake-induced ground motion and soil amplification. Hence, archaeoseismology explores pre-instrumental (past) earthquakes that might have affected sites of human occupation and their nearby settings, which have left their co-seismic marks in ancient manufactured constructions exhumed by archaeological excavations. However, archaeoseismological observations are often made on a limited epicentral area, poorly constrained dated earthquakes and occasionally on unclear evidence of earthquake damage. Archaeological excavations or field investigations often underestimate the critical role that an archaeological site’s ancient geological site conditions might have played in causing co-seismic structural damage to ancient anthropogenic structures. Nevertheless, the archaeological community might document and inaccurately diagnose structural damage by ancient earthquake shaking to structures and even estimate the size of past earthquakes giving little or no consideration to the role of geological site effects in addressing the causative earthquake. 
  • 389
  • 22 Mar 2023
  • Page
  • of
  • 6
Featured Entry Collections
>>

Featured Books

>>
Encyclopedia of Social Sciences
Encyclopedia of COVID-19
Encyclopedia of Fungi
Encyclopedia of Digital Society, Industry 5.0 and Smart City
ScholarVision Creations
Feedback