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Akimotoite
Akimotoite is a rare silicate mineral in the ilmenite group of minerals, with the chemical formula . It is polymorphous with pyroxene and with bridgmanite, a natural silicate perovskite that is the most abundant mineral in Earth's silicate mantle. Akimotoite has a vitreous luster, is colorless, and has a white or colorless streak. It crystallizes in the trigonal crystal system in space group R. It is the silicon analogue of geikielite (MgTiO3). Crystal structure The crystal structure is similar to that of ilmenite (FeTiO3) with Si and Mg in regular octahedral coordination with oxygen. The Si and Mg octahedra align in discrete layers alternating up the c-axis. The space group is R (trigonal) with a = 4.7284 Å; c = 13.5591 Å; V = 262.94 Å3; Z = 6.Horiuchi, H., Hirano, M., Ito, E., and Matsui, Y. (1982) MgSiO3 (ilmenite-type): single crystal X-ray diffraction study. American Mineralogist, 67, 788-793 Occurrence Akimotoite was found in the Tenham meteorites in Queen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxide Minerals
The oxide mineral class includes those minerals in which the oxide anion (O2−) is bonded to one or more metal alloys. The hydroxide-bearing minerals are typically included in the oxide class. Minerals with complex anion groups such as the Silicate mineral, silicates, Sulfate mineral, sulfates, carbonate mineral, carbonates and Phosphate mineral, phosphates are classed separately. Simple oxides *XO form **Periclase group ***Periclase ***Manganosite **Zincite group ***Zincite ***Bromellite ***Tenorite ***Litharge * form **Cuprite **Ice * form **Hematite group ***Corundum ***Hematite ***Ilmenite * form **Rutile group ***Rutile ***Pyrolusite ***Cassiterite **Baddeleyite **Uraninite **Thorianite * form **Spinel group ***Spinel ***Gahnite ***Magnetite ***Franklinite ***Chromite **Chrysoberyl **Columbite *Hydroxide subgroup: **Brucite **Manganite **Romanèchite **Goethite group: ***Diaspore ***Goethite Nickel–Strunz class 4: oxides Internationa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meteorite Minerals
A meteorite is a rock that originated in outer space and has fallen to the surface of a planet or moon. When the original object enters the atmosphere, various factors such as friction, pressure, and chemical interactions with the atmospheric gases cause it to heat up and radiate energy. It then becomes a meteor and forms a fireball, also known as a shooting star; astronomers call the brightest examples " bolides". Once it settles on the larger body's surface, the meteor becomes a meteorite. Meteorites vary greatly in size. For geologists, a bolide is a meteorite large enough to create an impact crater. Meteorites that are recovered after being observed as they transit the atmosphere and impact Earth are called meteorite falls. All others are known as meteorite finds. Meteorites have traditionally been divided into three broad categories: stony meteorites that are rocks, mainly composed of silicate minerals; iron meteorites that are largely composed of ferronickel; and stony ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glossary Of Meteoritics
This is a glossary of terms used in meteoritics, the science of meteorites. # * 2 Pallas – an asteroid from the asteroid belt and one of the likely parent bodies of the CR meteorites. * 4 Vesta – second-largest asteroid in the asteroid belt and likely source of the HED meteorites. * 221 Eos – an asteroid from the asteroid belt and one of the likely parent bodies of the CO meteorites. * 289 Nenetta – an asteroid from the asteroid belt and one of the likely parent bodies of the angrites. * 3103 Eger – an asteroid from the asteroid belt and one of the likely parent bodies of the aubrites. * 3819 Robinson – an asteroid from the asteroid belt and one of the likely parent bodies of the angrites. * IAB meteorite, IA meteorite – an iron meteorite group now part of the IAB group/complex. * IAB meteorite – an iron meteorite and primitive achondrite of the IAB group/complex. * IAB meteorite, IB meteorite – an iron meteorite group now part of the IAB group/complex. * IC me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subduction
Subduction is a geological process in which the oceanic lithosphere and some continental lithosphere is recycled into the Earth's mantle at the convergent boundaries between tectonic plates. Where one tectonic plate converges with a second plate, the heavier plate dives beneath the other and sinks into the mantle. A region where this process occurs is known as a subduction zone, and its surface expression is known as an arc-trench complex. The process of subduction has created most of the Earth's continental crust. Rates of subduction are typically measured in centimeters per year, with rates of convergence as high as 11 cm/year. Subduction is possible because the cold and rigid oceanic lithosphere is slightly denser than the underlying asthenosphere, the hot, ductile layer in the upper mantle. Once initiated, stable subduction is driven mostly by the negative buoyancy of the dense subducting lithosphere. The down-going slab sinks into the mantle largely under its own ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earth's Mantle
Earth's mantle is a layer of silicate mineral, silicate rock between the Earth's crust, crust and the Earth's outer core, outer core. It has a mass of and makes up 67% of the mass of Earth. It has a thickness of making up about 46% of Earth's radius and 84% of Earth's volume. It is predominantly solid but, on geologic time scales, it behaves as a viscosity, viscous fluid, sometimes described as having the consistency of caramel. Partial melting of the mantle at mid-ocean ridges produces oceanic crust, and partial melting of the mantle at subduction zones produces continental crust. Structure Rheology Earth's upper mantle is divided into two major rheology, rheological layers: the rigid lithosphere comprising the uppermost mantle (the lithospheric mantle), and the more ductile asthenosphere, separated by the Lithosphere-Asthenosphere boundary, lithosphere-asthenosphere boundary. Lithosphere underlying ocean crust has a thickness of around , whereas lithosphere underlying cont ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Randall County, Texas
Randall County is a county located in the U.S. state of Texas. As of the 2020 census, its population was 140,753. Its county seat is Canyon. The county was created in 1876 and later organized in 1889. It is named for Horace Randal, a Confederate brigadier general killed at the Battle of Jenkins Ferry. The reason the county name differs from his is because the bill creating the county misspelled Randal's name. Randall County, alongside adjacent Potter County is part of the Amarillo metropolitan statistical area. At one time, the large JA Ranch, founded by Charles Goodnight and John George Adair, which reached into six counties, held acreage in Randall County. Geography According to the U.S. Census Bureau, the county has a total area of , of which (1.2%) are covered by water. Palo Duro Canyon, the second-largest canyon in the United States, is located in Randall County. Major highways * Interstate 27 * U.S. Highway 60 * U.S. Highway 87 * State Highway 217 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Umbarger Meteorite
Umbarger ( ) is a census-designated place in Randall County, Texas, United States. According to the Handbook of Texas, the community had an estimated population of 327 in 2000. The community is part of the Amarillo, Texas Metropolitan Statistical Area. History The origins of the community date back to the mid-1890s. In 1895, rancher S.G. Umbarger leased the site from the Houston and Great Northern Railroad survey lands. He purchased it two years later and established several businesses that catered to area settlers and travelers. The Panhandle and Santa Fe Railway established a switch near Umbarger's ranch in 1898. Although Umbarger sold his ranch and moved to nearby Canyon in 1900, the settlement retained its name. As more land was made available to homesteaders, the community slowly began to grow. In 1902, a group of German Catholics from the Schulenburg area in south central Texas settled in Umbarger. The migration was pioneered by Pius Friemel. A general store that hous ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nigeria
Nigeria, officially the Federal Republic of Nigeria, is a country in West Africa. It is situated between the Sahel to the north and the Gulf of Guinea in the Atlantic Ocean to the south. It covers an area of . With Demographics of Nigeria, a population of more than 230 million, it is the List of African countries by population, most populous country in Africa, and the List of countries and dependencies by population, world's sixth-most populous country. Nigeria borders Niger in Niger–Nigeria border, the north, Chad in Chad–Nigeria border, the northeast, Cameroon in Cameroon–Nigeria border, the east, and Benin in Benin–Nigeria border, the west. Nigeria is a Federation, federal republic comprising 36 States of Nigeria, states and the Federal Capital Territory, Nigeria, Federal Capital Territory, where its capital, Abuja, is located. The List of Nigerian cities by population, largest city in Nigeria by population is Lagos, one of the largest List of largest cities, metr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Katsina State
Katsina State ( ; 𞤤𞤫𞤴𞤣𞤭 𞤳𞤢𞥁𞤭𞤲𞤢) is a state in the northwestern geopolitical zone of Nigeria. It is bordered to the west by Zamfara State, to the east by Kano and Jigawa states, and to the south by Kaduna State, while its northern border forms part of the national border with Niger. The state capital is the city of Katsina, and the state is divided into 34 local government areas. The state is nicknamed the "Home of Hospitality". With an estimated population of 9.3 million residents as of 2023, Katsina State is the third most populous state in the country, despite the fact that it only ranks 17th out of 36 states in terms of area. Geographically, Katsina is primarily located within the West Sudanian savanna, although parts of the north of the state transition into the semi-desert Sahelian savanna. Major rivers in the state include the Bunsuru, Gada, and Sokoto rivers, which provide water for agriculture and settlements. Demographically ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
China
China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after India, representing 17.4% of the world population. China spans the equivalent of five time zones and Borders of China, borders fourteen countries by land across an area of nearly , making it the list of countries and dependencies by area, third-largest country by land area. The country is divided into 33 Province-level divisions of China, province-level divisions: 22 provinces of China, provinces, 5 autonomous regions of China, autonomous regions, 4 direct-administered municipalities of China, municipalities, and 2 semi-autonomous special administrative regions. Beijing is the country's capital, while Shanghai is List of cities in China by population, its most populous city by urban area and largest financial center. Considered one of six ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
