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Diapirism
A diapir (; , ) is a type of intrusion in which a more mobile and ductilely deformable material is forced into brittle overlying rocks. Depending on the tectonic environment, diapirs can range from idealized mushroom-shaped Rayleigh–Taylor instability structures in regions with low tectonic stress such as in the Gulf of Mexico to narrow dikes of material that move along tectonically induced fractures in surrounding rock. The term was introduced by Romanian geologist Ludovic Mrazek, who was the first to understand the principle of salt tectonics and plasticity. The term ''diapir'' may be applied to '' igneous intrusions'', but it is more commonly applied to non-igneous, relatively cold materials, such as salt domes and mud diapirs. If a salt diapir reaches the surface, it can flow because salt becomes ductile with a small amount of moisture, forming a salt glacier. Occurrence Differential loading causes salt deposits covered by overburden (sediment) to rise upward tow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salt Glacier
A salt glacier (or namakier) is a rare flow of salt that is created when a rising diapir in a salt dome breaches the surface of Earth. The name ‘salt glacier’ was given to this phenomenon due to the similarity of movement when compared with ice glaciers. The causes of these formations is primarily due to salt's unique properties and its surrounding geologic environment. A rising body of salt is referred to as a diapir; which rises to the surface and feeds the salt glacier. Salt structures are usually composed of halite, anhydrite, gypsum and clay minerals. Clays may be brought up with the salt, turning it dark. These salt flows are rare on Earth. In a more recent discovery, scientists have found that they also occur on Mars, but are composed of sulfates. A paper published in November 2023 suggests that salt glaciers composed of halite might also be present on Mercury. The salt glaciers of the Zagros Mountains in Iran are halite whereas the salt glacier of Lüneburg Kalkberg, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salt Tectonics
upright=1.7 Salt tectonics, or halokinesis, or halotectonics, is concerned with the geometries and processes associated with the presence of significant thicknesses of evaporites containing rock salt within a stratigraphic sequence of rocks. This is due both to the low density of salt, which does not increase with burial, and its low strength. Salt structures (excluding undeformed layers of salt) have been found in more than 120 sedimentary basins around the world. Passive salt structures Structures may form during continued sedimentary loading, without any external tectonic influence, due to gravitational instability. Pure halite has a density of 2160 kg/m3. When initially deposited, sediments generally have a lower density of 2000 kg/m3, but with loading and compaction their density increases to 2500 kg/m3, which is greater than that of salt. Once the overlying layers have become denser, the weak salt layer will tend to deform into a characteristic series of rid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salt Dome
A salt dome is a type of structural dome formed when salt (or other evaporite minerals) intrudes into overlying rocks in a process known as diapirism. Salt domes can have unique surface and subsurface structures, and they can be discovered using techniques such as seismic reflection. They are important in petroleum geology as they can function as petroleum traps. Formation Diagram showing formation of salt domes Stratigraphically, salt basins developed periodically from the Proterozoic to the Neogene. The formation of a salt dome begins with the deposition of salt in a restricted basin. In these basins, the outflow of water exceeds inflow. Specifically, the basin loses water through evaporation, resulting in the precipitation and deposition of salt. While the rate of sedimentation of salt is significantly larger than the rate of sedimentation of clastics, it is recognized that a single evaporation event is rarely enough to produce the vast quantities of salt needed to f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ludovic Mrazek
Ludovic Mrazec (July 17, 1867 in Craiova – June 9, 1944 in Bucharest) was a Romanian geologist and list of members of the Romanian Academy, member of the Romanian Academy. He introduced the term diapir that denotes a type of intrusion in which a more mobile and ductilely deformable material is forced into brittle overlying rocks. The phenomenon of "diapirism" allows rock salt to provide an effective trap for hydrocarbon deposits. In this way, Ludovic Mrazec explained the distribution of hydrocarbon accumulations in the Neogene Carpathian. Diapirism is commonly used as a basic concept in geological survey as well as in Planetary science.F. Nimmo, R. T. Pappalardo (2006), "Diapir-induced reorientation of Saturn's moon Enceladus" Nature 441, 614-616. References {{DEFAULTSORT:Mrazek, Ludovic 1867 births 1944 deaths People from Craiova Romanian people of Czech descent Romanian geologists Presidents of the Romanian Academy Ministers of industry and commerce of Romania People ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enceladus
Enceladus is the sixth-largest moon of Saturn and the 18th-largest in the Solar System. It is about in diameter, about a tenth of that of Saturn's largest moon, Titan. It is covered by clean, freshly deposited snow hundreds of meters thick, making it one of the most reflective bodies of the Solar System. Consequently, its surface temperature at noon reaches only , far colder than a light-absorbing body would be. Despite its small size, Enceladus has a wide variety of surface features, ranging from old, heavily cratered regions to young, tectonically deformed terrain. Enceladus was discovered on August 28, 1789, by William Herschel, but little was known about it until the two Voyager spacecraft, '' Voyager 1'' and '' Voyager 2'', flew by Saturn in 1980 and 1981. In 2005, the spacecraft '' Cassini'' started multiple close flybys of Enceladus, revealing its surface and environment in greater detail. In particular, ''Cassini'' discovered water-rich plumes venting fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Evaporite
An evaporite () is a water- soluble sedimentary mineral deposit that results from concentration and crystallization by evaporation from an aqueous solution. There are two types of evaporite deposits: marine, which can also be described as ocean deposits, and non-marine, which are found in standing bodies of water such as lakes. Evaporites are considered sedimentary rocks and are formed by chemical sediments. Formation Although all water bodies on the surface and in aquifers contain dissolved salts, the water must evaporate into the atmosphere for the minerals to precipitate. For this to happen, the water body must enter a restricted environment where water input into this environment remains below the net rate of evaporation. This is usually an arid environment with a small drainage basin fed by a limited input of water. When evaporation occurs, the remaining water is enriched in salts, and they precipitate after the water becomes saturated. Depositional environments ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stratum (geology)
In geology and related fields, a stratum (: strata) is a layer of rock or sediment characterized by certain lithologic properties or attributes that distinguish it from adjacent layers from which it is separated by visible surfaces known as either '' bedding surfaces'' or ''bedding planes''.Salvador, A. ed., 1994. ''International stratigraphic guide: a guide to stratigraphic classification, terminology, and procedure. 2nd ed.'' Boulder, Colorado, The Geological Society of America, Inc., 215 pp. . Prior to the publication of the International Stratigraphic Guide, older publications have defined a stratum as being either equivalent to a single bed or composed of a number of beds; as a layer greater than 1 cm in thickness and constituting a part of a bed; or a general term that includes both ''bed'' and ''lamina''.Neuendorf, K.K.E., Mehl, Jr., J.P., and Jackson, J.A. , eds., 2005. ''Glossary of Geology'' 5th ed. Alexandria, Virginia, American Geological Institute. 779 pp. . ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Well Drilling
Well drilling is the process of drilling a hole in the ground for the extraction of a natural resource such as ground water, brine, natural gas, or petroleum, for the injection of a fluid from surface to a subsurface reservoir or for subsurface formations evaluation or monitoring. Drilling for the exploration of the nature of the material underground (for instance in search of metallic ore) is best described as ''borehole'' drilling. The earliest wells were water wells, shallow pits dug by hand in regions where the water table approached the surface, usually with masonry or wooden walls lining the interior to prevent collapse. Modern drilling techniques utilize long drill shafts, producing holes much narrower and deeper than could be produced by digging. Well drilling can be done either manually or mechanically and the nature of required equipment varies from extremely simple and cheap to very sophisticated. In many jurisdictions, drilling activities are regulated to protec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galilean Thermometer
A Galileo thermometer (or Galilean thermometer) is a thermometer made of a sealed glass cylinder containing a clear liquid and several glass vessels of varying density. The individual floats rise or fall in relation to their respective density and the density of the surrounding liquid as the temperature changes. It is named after Galileo Galilei because he discovered the principle on which this thermometer is based—that the density of a liquid changes in relation to its temperature. History Although named after the 16th–17th-century physicist Galileo, the thermometer was not invented by him. (Galileo did invent a thermometer called Galileo's air thermometer, more accurately called a thermoscope, in or before 1603.) The instrument now known as a Galileo thermometer was invented by a group of academics and technicians known as the Accademia del Cimento of Florence, who included Galileo's pupil, Torricelli and Torricelli's pupil Viviani. Details of the thermometer were publis ... [...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] |
Magma
Magma () is the molten or semi-molten natural material from which all igneous rocks are formed. Magma (sometimes colloquially but incorrectly referred to as ''lava'') is found beneath the surface of the Earth, and evidence of magmatism has also been discovered on other terrestrial planets and some natural satellites. Besides molten rock, magma may also contain suspended crystals and volcanic gas, gas bubbles. Magma is produced by melting of the mantle (geology), mantle or the Crust (geology), crust in various tectonics, tectonic settings, which on Earth include subduction zones, continental rift (geology), rift zones, mid-ocean ridges and Hotspot (geology), hotspots. Mantle and crustal melts migrate upwards through the crust where they are thought to be stored in magma chambers or trans-crustal crystal mush, crystal-rich mush zones. During magma's storage in the crust, its composition may be modified by Fractional crystallization (geology), fractional crystallization, contaminati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
