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Geological Resistance
Geological resistance is a measure of how well minerals resist erosive factors, and is based primarily on hardness, chemical reactivity and cohesion. The more hardness, less reactivity and more cohesion a mineral has, the less susceptible it is to erosion. Over time, differences in geological resistance in the same geological formation can lead to the formation of columns and arches, like those in Moab, Utah Moab () is the largest city and county seat of Grand County in eastern Utah in the western United States, known for its dramatic scenery. The population was 5,366 at the 2020 census. Moab attracts many tourists annually, mostly visitors to ...; and of bridges, like Utah's Rainbow Bridge. References Weathering {{Geology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mineral
In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid chemical compound with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.John P. Rafferty, ed. (2011): Minerals'; p. 1. In the series ''Geology: Landforms, Minerals, and Rocks''. Rosen Publishing Group. The geological definition of mineral normally excludes compounds that occur only in living organisms. However, some minerals are often biogenic (such as calcite) or are organic compounds in the sense of chemistry (such as mellite). Moreover, living organisms often synthesize inorganic minerals (such as hydroxylapatite) that also occur in rocks. The concept of mineral is distinct from rock, which is any bulk solid geologic material that is relatively homogeneous at a large enough scale. A rock may consist of one type of mineral, or may be an aggregate of two or more different types of minerals, spacially segregated into distinct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mohs Hardness
The Mohs scale of mineral hardness () is a qualitative ordinal scale, from 1 to 10, characterizing scratch resistance of various minerals through the ability of harder material to scratch softer material. The scale was introduced in 1812 by the German geologist and mineralogist Friedrich Mohs, in his book ''"Versuch einer Elementar-Methode zur naturhistorischen Bestimmung und Erkennung der Fossilien"''; it is one of several definitions of hardness in materials science, some of which are more quantitative. The method of comparing hardness by observing which minerals can scratch others is of great antiquity, having been mentioned by Theophrastus in his treatise ''On Stones'', , followed by Pliny the Elder in his ''Naturalis Historia'', . The Mohs scale is useful for identification of minerals in the field, but is not an accurate predictor of how well materials endure in an industrial setting – ''toughness''. Minerals The Mohs scale of mineral hardness is based on the ability ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Reactivity
In chemistry, reactivity is the impulse for which a chemical substance undergoes a chemical reaction, either by itself or with other materials, with an overall release of energy. ''Reactivity'' refers to: * the chemical reactions of a single substance, * the chemical reactions of two or more substances that interact with each other, * the systematic study of sets of reactions of these two kinds, * methodology that applies to the study of reactivity of chemicals of all kinds, * experimental methods that are used to observe these processes * theories to predict and to account for these processes. The chemical reactivity of a single substance (reactant) covers its behavior in which it: * Decomposes * Forms new substances by addition of atoms from another reactant or reactants * Interacts with two or more other reactants to form two or more products The chemical reactivity of a substance can refer to the variety of circumstances (conditions that include temperature, pressure, pres ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cohesion (chemistry)
Cohesion (), also called cohesive attraction or cohesive force, is the action or property of like molecules sticking together, being mutually attractive. It is an intrinsic property of a substance that is caused by the shape and structure of its molecules, which makes the distribution of surrounding electrons irregular when molecules get close to one another, creating electrical attraction that can maintain a microscopic structure such as a water drop. Cohesion allows for surface tension, creating a "solid-like" state upon which light-weight or low-density materials can be placed. Water, for example, is strongly cohesive as each molecule may make four hydrogen bonds to other water molecules in a tetrahedral configuration. This results in a relatively strong Coulomb force between molecules. In simple terms, the polarity (a state in which a molecule is oppositely charged on its poles) of water molecules allows them to be attracted to each other. The polarity is due to th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moab, Utah
Moab () is the largest city and county seat of Grand County in eastern Utah in the western United States, known for its dramatic scenery. The population was 5,366 at the 2020 census. Moab attracts many tourists annually, mostly visitors to the nearby Arches and Canyonlands National Parks. The town is a popular base for mountain bikers who ride the extensive network of trails including the Slickrock Trail, and for off-roaders who come for the annual Moab Jeep Safari. History Early years The Biblical name Moab refers to an area of land located on the eastern side of the Jordan River. Some historians believe the city in Utah came to use this name because of William Andrew Peirce, the first postmaster, believing that the biblical Moab and this part of Utah were both "the far country". However, others believe the name has Paiute origins, referring to the word ''moapa'', meaning "mosquito". Some of the area's early residents attempted to change the city's name, because in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rainbow Bridge National Monument
Rainbow Bridge National Monument is administered by Glen Canyon National Recreation Area, southern Utah, United States. Rainbow Bridge is often described as the world's highest natural bridge. The span of Rainbow Bridge was reported in 1974 by the Bureau of Reclamation to be , but a measurement of span according to definition by the Natural Arch and Bridge Society in 2007 resulted in a value of . At the top it is thick and wide. The bridge, which is of cultural importance to a number of area Native American tribes, has been designated a Traditional Cultural Property by the National Park Service. Size Two other natural arches, Kolob Arch and Landscape Arch, both also in southern Utah, have confirmed spans several meters longer than Rainbow Bridge, but by most definitions of the terms they are considered to be arches rather than bridges. With a height of Rainbow Bridge does indeed stand taller than either of its longer competitors, but it is outdone by Aloba Arch in Ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
