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Palygorskite
Palygorskite (Russian: Палыгорскит) or attapulgite is a magnesium aluminium phyllosilicate with the chemical formula ) that occurs in a type of clay soil common to the Southeastern United States. It is one of the types of fuller's earth. Some smaller deposits of this mineral can be found in Mexico, where its use is tied to the manufacture of Maya blue in pre-Columbian times. Name Palygorskite was first described in 1862 for a deposit at Palygorskaya on the Popovka River, Middle Urals, Permskaya Oblast, Russia. The synonym ''attapulgite'' is derived from the U.S. town of Attapulgus, in the extreme southwest corner of the state of Georgia, where the mineral is abundant and surface-mined. Origin Five processes for the genesis of palygorskite were discussed in the older literature: # Formation under arid conditions, # Formation connected with the weathering of basalt, # Hydrothermal genesis, # Synsedimentary (during sedimentary deposition) authigenesis, # Postsedi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maya Blue
Maya blue () is a unique bright turquoise or azure blue pigment manufactured by cultures of pre-Columbian Mesoamerica, such as the Mayas and Aztecs, during a period extending from approximately the 8th century to around 1860 CE. It is found in mural paintings on architectural buildings, ceramic pieces, sculptures, codices, and even in post-conquest Indochristian artworks and mural decorations. Manufacture The Maya blue pigment is a composite of organic and inorganic constituents, primarily indigo dyes derived from the leaves of anil (''Indigofera suffruticosa'', called ''ch'oj'' in Mayan) plants combined with palygorskite, a natural clay and type of fuller's earth. Palygorskite is most common in the Southern United States, but is not known to exist in abundant deposits in Mesoamerica.Arnold (2005); Haude (1997). Smaller trace amounts of other mineral additives have also been identified. Historical use Maya blue first appeared around 800, and it was still used in the 16th c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phyllosilicate
Silicate minerals are rock-forming minerals made up of silicate groups. They are the largest and most important class of minerals and make up approximately 90 percent of Earth's crust. In mineralogy, the crystalline forms of silica (silicon dioxide, ) are usually considered to be Silicate mineral#Tectosilicates, tectosilicates, and they are classified as such in the Dana system (75.1). However, the Nickel-Strunz system classifies them as oxide minerals (4.DA). Silica is found in nature as the mineral quartz, and its polymorphism (materials science), polymorphs. On Earth, a wide variety of silicate minerals occur in an even wider range of combinations as a result of the processes that have been forming and re-working the crust for billions of years. These processes include partial melting, crystallization, fractionation, metamorphism, weathering, and diagenesis. Living organisms also contribute to this carbonate–silicate cycle, geologic cycle. For example, a type of plankton ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hnúšťa
Hnúšťa () is a town and municipality in the Rimavská Sobota District of the Banská Bystrica Region of southern Slovakia. It is the birthplace of the well-known 19th-century Slovak writer and member of the Štúr generation, Ján Francisci-Rimavský. He is commemorated by a statue and a plaque near the town's main square. History The town was first mentioned in 1334. Geography Hnúšťa lies at an altitude of above sea level and covers an area of . It is located in the Slovenské rudohorie mountains, in the Rimava river valley near Rimavská Sobota. Demographics According to the 2001 census, 93.12% of inhabitants were Slovaks, 3.36% Roma, 1.07% Hungarians and 0.40% Czechs. The religious make-up was 36.40% Roman Catholics, 21.62% Lutherans and 35.44% people with no religious affiliation. Economy A factory for the production of chemicals was one of the main employers in Hnúšťa region. Now several middle sized companies are located in the town industrial park. The lo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrothermal
Hydrothermal circulation in its most general sense is the circulation of hot water (Ancient Greek ὕδωρ, ''water'',Liddell, H.G. & Scott, R. (1940). ''A Greek-English Lexicon. revised and augmented throughout by Sir Henry Stuart Jones. with the assistance of. Roderick McKenzie.'' Oxford: Clarendon Press. and θέρμη, ''heat'' ). Hydrothermal circulation occurs most often in the vicinity of sources of heat within the Earth's crust. In general, this occurs near volcanic activity, but can occur in the shallow to mid crust along deeply penetrating fault irregularities or in the deep crust related to the intrusion of granite, or as the result of orogeny or metamorphism. Hydrothermal circulation often results in hydrothermal mineral deposits. Seafloor hydrothermal circulation Hydrothermal circulation in the oceans is the passage of the water through mid-oceanic ridge systems. The term includes both the circulation of the well-known, high-temperature vent waters near the ridge c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basalt
Basalt (; ) is an aphanite, aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the planetary surface, surface of a terrestrial planet, rocky planet or natural satellite, moon. More than 90% of all volcanic rock on Earth is basalt. Rapid-cooling, fine-grained basalt is chemically equivalent to slow-cooling, coarse-grained gabbro. The eruption of basalt lava is observed by geologists at about 20 volcanoes per year. Basalt is also an important rock type on other planetary bodies in the Solar System. For example, the bulk of the plains of volcanism on Venus, Venus, which cover ~80% of the surface, are basaltic; the lunar mare, lunar maria are plains of flood-basaltic lava flows; and basalt is a common rock on the surface of Mars. Molten basalt lava has a low viscosity due to its relatively low silica content (between 45% and 52%), resulting in rapidly moving lava flo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Weathering
Weathering is the deterioration of rocks, soils and minerals (as well as wood and artificial materials) through contact with water, atmospheric gases, sunlight, and biological organisms. It occurs '' in situ'' (on-site, with little or no movement), and so is distinct from erosion, which involves the transport of rocks and minerals by agents such as water, ice, snow, wind, waves and gravity. Weathering processes are either physical or chemical. The former involves the breakdown of rocks and soils through such mechanical effects as heat, water, ice and wind. The latter covers reactions to water, atmospheric gases and biologically produced chemicals with rocks and soils. Water is the principal agent behind both kinds, though atmospheric oxygen and carbon dioxide and the activities of biological organisms are also important. Biological chemical weathering is also called biological weathering. The materials left after the rock breaks down combine with organic material to create so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aridity
Aridity is the condition of geographical regions which make up approximately 43% of total global available land area, characterized by low annual precipitation, increased temperatures, and limited water availability.Perez-Aguilar, L. Y., Plata-Rocha, W., Monjardin-Armenta, S. A., Franco-Ochoa, C., & Zambrano-Medina, Y. G. (2021). The Identification and Classification of Arid Zones through Multicriteria Evaluation and Geographic Information Systems—Case Study: Arid Regions of Northwest Mexico. ''ISPRS International Journal of Geo-Information'', ''10''(11), 720. https://doi.org/10.3390/ijgi10110720 These areas tend to fall upon degraded soils, and their health and functioning are key necessities of regulating ecosystems’ atmospheric components. Change over time The distribution of aridity at any time is largely the result of the general circulation of the atmosphere. The latter does change significantly over time through climate change Present-day climate chang ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surface Mining
Surface mining, including strip mining, open-pit mining and mountaintop removal mining, is a broad category of mining in which soil and rock overlying the mineral deposit (the overburden) are removed, in contrast to underground mining, in which the overlying rock is left in place, and the mineral is removed through shafts or tunnels. In North America, where the majority of surface coal mining occurs, this method began to be used in the mid-16th century and is practiced throughout the world in the mining of many different minerals. In North America, surface mining gained popularity throughout the 20th century, and surface mines now produce most of the coal mined in the United States. In most forms of surface mining, heavy equipment, such as earthmovers, first remove the overburden. Next, large machines, such as dragline excavators or bucket-wheel excavators, extract the mineral. Advantages of surface mining include lower cost and greater safety compared to underground mini ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Georgia (U
Georgia most commonly refers to: * Georgia (country), a country in the South Caucasus * Georgia (U.S. state), a state in the southeastern United States Georgia may also refer to: People and fictional characters * Georgia (name), a list of people and fictional characters with the female given name * Georgia (musician) (born 1990), English singer, songwriter, and drummer Georgia Barnes Places Historical polities * Kingdom of Georgia, a medieval kingdom * Kingdom of Eastern Georgia, a late medieval kingdom * Kingdom of Western Georgia, a late medieval kingdom * Georgia Governorate, a subdivision of the Russian Empire * Georgia within the Russian Empire * Democratic Republic of Georgia, a country established after the collapse of the Russian Empire and later conquered by Soviet Russia. * Georgian Soviet Socialist Republic, a republic within the Soviet Union * Republic of Georgia (1990–1992), Republic of Georgia, a republic in the Soviet Union which, after the collapse of the U ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Attapulgus, Georgia
Attapulgus is a city in Decatur County, Georgia, United States. As of the 2020 census, the city had a population of 454, up from 449 at the 2010 census. It is part of the Bainbridge, Georgia Micropolitan Statistical Area. The town's name is a Muscogee word meaning "Dogwood"; due to the abundance of attapulgite, which makes up the clay soil throughout much of the Southeast, the mineral was named after the town. Attapulgus was the birthplace of civil rights leader Hosea Williams (1926–2000), who is said to have been run out of town by a lynch mob at the age of 13. He is remembered around the world for his close association with Dr. Martin Luther King Jr., and for leading, with John Lewis, the famous march across the Edmund Pettus Bridge in Selma, Alabama, in 1965 that led to the passage of the landmark Voting Rights Act of 1965. Williams served on the Atlanta City Council, the DeKalb County Commission, and in the Georgia Senate. He also started a program to feed the hungry t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Permskaya Oblast
Until 1 December 2005, Perm Oblast () was a federal subject of Russia (an oblast) in Privolzhsky (Volga) Federal District. According to the results of the referendum held in October 2004, Perm Oblast was merged with Komi-Permyak Autonomous Okrug to form Perm Krai. It was established in 1938 as part of the RSFSR. From 1940 to 1957 it was named Molotov Oblast in honor of Vyacheslav Molotov. The oblast was named after its administrative center, the city of Perm. The oblast covered an area of 160,600 km2, and as of the 2002 census its population was 2,819,421. Before the merger, neighboring oblasts and republics were (from north clockwise) Komi Republic, Sverdlovsk Oblast, Republic of Bashkortostan, Udmurt Republic, and Kirov Oblast. Geography Time zone Perm Oblast was located in the Yekaterinburg Time Zone (YEKT/YEKST). UTC Coordinated Universal Time (UTC) is the primary time standard globally used to regulate clocks and time. It establishes a reference for the current ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
