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Glaucophane Ridge
Glaucophane is the name of a mineral and a mineral group belonging to the sodic amphibole supergroup of the double chain inosilicates, with the chemical formula ☐Na2(Mg3Al2)Si8O22(OH)2. Glaucophane crystallizes in the monoclinic system. Name Glaucophane is named for its typical blue color. In Greek, ''glaucophane'' means "blue appearing". As the major mineral component, it is glaucophane's color that gives the "blueschist" metamorphic rock type its name. Characteristics The blue color is very diagnostic for this species. Glaucophane, along with the closely related mineral riebeckite, to which it forms a series with, and their intermediate crossite, are the only well known amphiboles that are commonly blue. Glaucophane forms a solid solution series with ferroglaucophane (). Glaucophane is the magnesium-rich endmember and ferroglaucophane is the iron-rich endmember. Ferroglaucophane is similar to glaucophane but is slightly denser and hence increased specific gravity. The two ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inosilicates
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, silica (silicon dioxide, ) is usually considered a silicate mineral. Silica is found in nature as the mineral quartz, and its 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 geologic cycle. For example, a type of plankton known as diatoms construct their exoskeletons ("frustules") from silica extracted from seawater. The frustules of dead diatoms are a major constituent of deep ocean sediment, and of diatomaceous earth. General structure A silicate mineral is generally an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron
Iron () is a chemical element with symbol Fe (from la, ferrum) and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, right in front of oxygen (32.1% and 30.1%, respectively), forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust. In its metallic state, iron is rare in the Earth's crust, limited mainly to deposition by meteorites. Iron ores, by contrast, are among the most abundant in the Earth's crust, although extracting usable metal from them requires kilns or furnaces capable of reaching or higher, about higher than that required to smelt copper. Humans started to master that process in Eurasia during the 2nd millennium BCE and the use of iron tools and weapons began to displace copper alloys, in some regions, only around 1200 BCE. That event is considered the transition from the Bronze Age to the Iron A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Minerals
Sodium is a chemical element with the symbol Na (from Latin ''natrium'') and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium is an alkali metal, being in group 1 of the periodic table. Its only stable isotope is 23Na. The free metal does not occur in nature, and must be prepared from compounds. Sodium is the sixth most abundant element in the Earth's crust and exists in numerous minerals such as feldspars, sodalite, and halite (NaCl). Many salts of sodium are highly water-soluble: sodium ions have been leached by the action of water from the Earth's minerals over eons, and thus sodium and chlorine are the most common dissolved elements by weight in the oceans. Sodium was first isolated by Humphry Davy in 1807 by the electrolysis of sodium hydroxide. Among many other useful sodium compounds, sodium hydroxide (lye) is used in soap manufacture, and sodium chloride (edible salt) is a de-icing agent and a nutrient for animals including human ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Minerals
This is a list of minerals for which there are articles on Wikipedia. Minerals are distinguished by various chemical and physical properties. Differences in chemical composition and crystal structure distinguish the various ''species''. Within a mineral species there may be variation in physical properties or minor amounts of impurities that are recognized by mineralogists or wider society as a mineral ''variety''. Mineral variety names are listed after the valid minerals for each letter. For a more complete listing of all mineral names, see List of minerals recognized by the International Mineralogical Association. A :Varieties that are not valid species: *Adamantine spar (variety of corundum) *Agate (variety of chalcedony and quartz) *Alabaster (variety of gypsum) *Alexandrite (variety of chrysoberyl) *Allingite (synonym of amber) *Alum *Amazonite (variety of microcline) *Amethyst (purple variety of quartz) *Ametrine (variety of quartz) *Ammolite (organic; also a gems ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Holmquistite
Holmquistite is a lithium magnesium aluminium inosilicate mineral with chemical formula . It crystallizes in the orthorhombic crystal system as prismatic crystals up to or as massive aggregates. It has a Mohs hardness of 5-6 and a specific gravity of 2.95 to 3.13. Color could vary from black, dark violet to light sky blue. It occurs as metasomatic replacements on the margins of lithium rich pegmatites. It was first described in 1913 from an occurrence in Utö, near Stockholm, Sweden. It was named for the Swedish petrologist Per Johan Holmquist Per is a Latin preposition which means "through" or "for each", as in per capita. Per or PER may also refer to: Places * IOC country code for Peru * Pér, a village in Hungary * Chapman code for Perthshire, historic county in Scotland Math ... (1866–1946). References Inosilicates Orthorhombic minerals Minerals in space group 62 {{silicate-mineral-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eclogite
Eclogite () is a metamorphic rock containing garnet (almandine-pyrope) hosted in a matrix of sodium-rich pyroxene (omphacite). Accessory minerals include kyanite, rutile, quartz, lawsonite, coesite, amphibole, phengite, paragonite, zoisite, dolomite, corundum and, rarely, diamond. The chemistry of primary and accessory minerals is used to classify three types of eclogite (A, B, and C). The broad range of eclogitic compositions has led a longstanding debate on the origin of eclogite xenoliths as subducted, altered oceanic crust. Origins Eclogites typically result from high to ultrahigh pressure metamorphism of mafic rock at low thermal gradients of < as it is subducted to the lower crust to depths in a subduction zone. Class ...
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Mantle (geology)
A mantle is a layer inside a planetary body bounded below by a Planetary core, core and above by a Crust (geology), crust. Mantles are made of Rock (geology), rock or Volatiles, ices, and are generally the largest and most massive layer of the planetary body. Mantles are characteristic of planetary bodies that have undergone planetary differentiation, differentiation by density. All Terrestrial planet, terrestrial planets (including Earth), a number of Asteroid, asteroids, and some planetary Natural satellite, moons have mantles. Earth's mantle The Earth's mantle is a layer of Silicate minerals, silicate rock between the Crust (geology), crust and the Earth's outer core, outer core. Its mass of 4.01 × 1024 kg is 67% the mass of the Earth. It has a thickness of making up about 84% of Earth's volume. It is predominantly solid, but in Geologic time scale, geological time it behaves as a Viscosity, viscous fluid. Partial melting of the mantle at mid-ocean ridges produ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subduction
Subduction is a geological process in which the oceanic lithosphere is recycled into the Earth's mantle at convergent boundaries. Where the oceanic lithosphere of a tectonic plate converges with the less dense lithosphere of a second plate, the heavier plate dives beneath the second plate 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 the average rate of convergence being approximately two to eight centimeters per year along most plate boundaries. Subduction is possible because the cold oceanic lithosphere is slightly denser than the underlying asthenosphere, the hot, ductile layer in the upper mantle underlying the cold, rigid lithosphere. Once initiated, stable subduction is driven mostly by the negative buoyancy of the de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metamorphism
Metamorphism is the transformation of existing rock (the protolith) to rock with a different mineral composition or texture. Metamorphism takes place at temperatures in excess of , and often also at elevated pressure or in the presence of chemically active fluids, but the rock remains mostly solid during the transformation. Metamorphism is distinct from weathering or diagenesis, which are changes that take place at or just beneath Earth's surface. Various forms of metamorphism exist, including regional, contact, hydrothermal, shock, and dynamic metamorphism. These differ in the characteristic temperatures, pressures, and rate at which they take place and in the extent to which reactive fluids are involved. Metamorphism occurring at increasing pressure and temperature conditions is known as ''prograde metamorphism'', while decreasing temperature and pressure characterize ''retrograde metamorphism''. Metamorphic petrology is the study of metamorphism. Metamorphic petrologists re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium
Sodium is a chemical element with the symbol Na (from Latin ''natrium'') and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium is an alkali metal, being in group 1 of the periodic table. Its only stable isotope is 23Na. The free metal does not occur in nature, and must be prepared from compounds. Sodium is the sixth most abundant element in the Earth's crust and exists in numerous minerals such as feldspars, sodalite, and halite (NaCl). Many salts of sodium are highly water-soluble: sodium ions have been leached by the action of water from the Earth's minerals over eons, and thus sodium and chlorine are the most common dissolved elements by weight in the oceans. Sodium was first isolated by Humphry Davy in 1807 by the electrolysis of sodium hydroxide. Among many other useful sodium compounds, sodium hydroxide (lye) is used in soap manufacture, and sodium chloride (edible salt) is a de-icing agent and a nutrient for animals including h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lawsonite
Lawsonite is a hydrous calcium aluminium sorosilicate mineral with formula CaAl2Si2O7(OH)2·H2O. Lawsonite crystallizes in the orthorhombic system in prismatic, often tabular crystals. Crystal twinning is common. It forms transparent to translucent colorless, white, and bluish to pinkish grey glassy to greasy crystals. Refractive indices are nα=1.665, nβ=1.672 - 1.676, and nγ=1.684 - 1.686. It is typically almost colorless in thin section, but some lawsonite is pleochroic from colorless to pale yellow to pale blue, depending on orientation. The mineral has a Mohs hardness of 8 and a specific gravity of 3.09. It has perfect cleavage in two directions and a brittle fracture. Lawsonite is a metamorphic mineral typical of the blueschist facies. It also occurs as a secondary mineral in altered gabbro and diorite. Associate minerals include epidote, titanite, glaucophane, garnet and quartz. It is an uncommon constituent of eclogite. Lawsonite was first described in 1895 for occurren ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metamorphic Facies
A metamorphic facies is a set of mineral assemblages in metamorphic rocks formed under similar pressures and temperatures.Essentials of Geology, 3rd Edition, Stephen Marshak The assemblage is typical of what is formed in conditions corresponding to an area on the two dimensional graph of temperature vs. pressure (See diagram in Figure 1). Rocks which contain certain minerals can therefore be linked to certain tectonics, tectonic settings, times and places in the geological history of the area. The boundaries between facies (and corresponding areas on the temperature v. pressure graph) are wide because they are gradational and approximate. The area on the graph corresponding to rock formation at the lowest values of temperature and pressure is the range of formation of sedimentary rocks, as opposed to metamorphic rocks, in a process called diagenesis. Historic definition The name ''facies'' was first used for specific Sedimentary depositional environment, sedimentary environments i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
