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Coranzulí (caldera)
Coranzuli is a back-arc caldera in the Andes, related to the Altiplano-Puna volcanic complex. It formed along the Lipez geological lineament about 6.6 million years ago. Volcanic ash samples found in the Coastal Cordillera of Chile may come from this volcano. The Rachaite () stratovolcano is located close to the caldera. The formation of this caldera has been influenced by a number of local fault systems, the Coyaguayama and Rachaite lineaments. Marine sediments of Ordovician age with some later volcanic intrusions form the basement together with Cretaceous-Eocene sediments. Three cycles of volcanic activity preceding the Coranzuli ignimbrite have been identified. The Coranzuli system is part of a Late Miocene volcanic episode that also includes Aguas Calientes, Cerro Panizos and the Toconquis ignimbrite of Galan. The Morro Grande Formation may have originated by volcanic activity in the area of Cerro Coranzuli. 6.8 to 6.4 million years ago, this caldera erupted the Coranzul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Back-arc
A back-arc basin is a type of geologic basin, found at some convergent plate boundaries. Presently all back-arc basins are submarine features associated with island arcs and subduction zones, with many found in the western Pacific Ocean. Most of them result from tensional forces, caused by a process known as oceanic trench rollback, where a subduction zone moves towards the subducting plate. Back-arc basins were initially an unexpected phenomenon in plate tectonics, as convergent boundaries were expected to universally be zones of compression. However, in 1970, Dan Karig published a model of back-arc basins consistent with plate tectonics. Structural characteristics Back-arc basins are typically very long and relatively narrow, often thousands of kilometers long while only being a few hundred kilometers wide at most. For back-arc extension to form, a subduction zone is required, but not all subduction zones have a back-arc extension feature. Back-arc basins are found in area ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Morro Grande Formation
Morro (Spanish and Portuguese for "hill") may refer to: Buildings *El Morro mine, Atacama, Chile *El Morro National Monument, New Mexico * Morro del Tulcán, pyramid in Popayán, Cauca *Morro Castle (Havana), fortress in Havana, Cuba * El Morro de San Felipe, fortress in Puerto Plata, Dominican Republic *Castillo San Felipe del Morro, a citadel in San Juan, Puerto Rico Geology *Morro Rock, a volcanic plug located just offshore from Morro Bay, California * Isla El Morro, island near Acapulco, Mexico *Isla El Morro, small island near Taboga Island, Panama Places ;Brazil * Morro Agudo, a municipality in the state of São Paulo * Morro Agudo de Goiás, a municipality in the state of Goiás * Morro Cabeça no Tempo, a municipality in the state of Piauí * Morro da Fumaça, a municipality in the state of Santa Catarina * Morro do Chapéu, a municipality in the state of Bahia * Morro do Chapéu do Piauí, a municipality in the state of Piauí * Morro da Garça, a municipality in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanoes Of Jujuy Province
A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most often found where tectonic plates are diverging or converging, and most are found underwater. For example, a mid-ocean ridge, such as the Mid-Atlantic Ridge, has volcanoes caused by divergent tectonic plates whereas the Pacific Ring of Fire has volcanoes caused by convergent tectonic plates. Volcanoes can also form where there is stretching and thinning of the crust's plates, such as in the East African Rift and the Wells Gray-Clearwater volcanic field and Rio Grande rift in North America. Volcanism away from plate boundaries has been postulated to arise from upwelling diapirs from the core–mantle boundary, deep in the Earth. This results in hotspot volcanism, of which the Hawaiian hotspot is an example. Volcanoes are usually not created where two tectonic plates slide pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seismic
Seismology (; from Ancient Greek σεισμός (''seismós'') meaning "earthquake" and -λογία (''-logía'') meaning "study of") is the scientific study of earthquakes and the propagation of elastic waves through the Earth or through other planet-like bodies. It also includes studies of earthquake environmental effects such as tsunamis as well as diverse seismic sources such as volcanic, tectonic, glacial, fluvial, oceanic, atmospheric, and artificial processes such as explosions. A related field that uses geology to infer information regarding past earthquakes is paleoseismology. A recording of Earth motion as a function of time is called a seismogram. A seismologist is a scientist who does research in seismology. History Scholarly interest in earthquakes can be traced back to antiquity. Early speculations on the natural causes of earthquakes were included in the writings of Thales of Miletus (c. 585 BCE), Anaximenes of Miletus (c. 550 BCE), Aristotle (c. 340 BCE), and Zhan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dacitic
Dacite () is a volcanic rock formed by rapid solidification of lava that is high in silica and low in alkali metal oxides. It has a fine-grained (aphanitic) to porphyritic texture and is intermediate in composition between andesite and rhyolite. It is composed predominantly of plagioclase feldspar and quartz. Dacite is relatively common, occurring in many tectonic settings. It is associated with andesite and rhyolite as part of the subalkaline tholeiitic and calc-alkaline magma series. Composition Dacite consists mostly of plagioclase feldspar and quartz with biotite, hornblende, and pyroxene ( augite or enstatite). The quartz appears as rounded, corroded phenocrysts, or as an element of the ground-mass. The plagioclase in dacite ranges from oligoclase to andesine and labradorite. Sanidine occurs, although in small proportions, in some dacites, and when abundant gives rise to rocks that form transitions to the rhyolites. The relative proportions of feldspars and quartz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhyodacitic
Rhyodacite is a volcanic rock intermediate in composition between dacite and rhyolite. It is the extrusive equivalent of those plutonic rocks that are intermediate in composition between monzogranite and granodiorite. Rhyodacites form from rapid cooling of lava relatively rich in silica and low in alkali metal oxides. Description Under IUGS guidelines, rhyodacites are not formally defined in either the QAPF classification, used to classify igneous rocks by their mineral content, or the TAS classification, used to classify volcanic rocks chemically. However, the IUGS allows the use of the term to describe rocks close to the boundary between the rhyolite and dacite fields in each classification scheme. Rhyodacite then describes a fine-grained igneous rock containing between 20% and 60% quartz and in which plagioclase makes up about two-thirds of the total feldspar content. Such a rock will contain between 69% and 72% silica by weight. The U.S. Geological Survey defines rhyodaci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coranzuli Ignimbrite
Coranzuli is a rural municipality and village in Jujuy Province in Argentina. Climate References {{coord, 23, 02, S, 66, 24, W, display=title, region:AR_type:city_source:GNS-enwiki Populated places in Jujuy Province ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cerro Galán
Cerro is Spanish for "hill" or "mountain". Toponyms ;Bolivia: * Cerro Rico, the "Rich Mountain" containing silver ore near Potosi, Bolivia ;Brazil: *Cerro Branco, a municipality of Rio Grande do Sul *Cerro Grande, Rio Grande do Sul, a municipality of Rio Grande do Sul * Cerro Largo, a municipality of Rio Grande do Sul ;Chile * Cerro de Los Inocentes, in the Juan Fernández Islands ;Cuba: * Cerro, Havana, a district (''municipio'') ;Italy: *Cerro (Bottanuco), a subdivision of Bottanuco in the province of Bergamo *Cerro al Lambro, in the province of Milano *Cerro al Volturno, in the province of Isernia * Cerro Maggiore, in the province of Milano *Cerro Tanaro, in the province of Asti * Cerro Veronese, in the province of Verona ;Mexico: * Cerro Potosí ;United States: * Cerro, New Mexico ;Uruguay: * Cerro Largo Department * Villa del Cerro, in Montevideo * Fortaleza del Cerro, in Montevideo Football clubs * C.A. Cerro, a football club from Montevideo, Uruguay * Club Ce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caldera
A caldera ( ) is a large cauldron-like hollow that forms shortly after the emptying of a magma chamber in a volcano eruption. When large volumes of magma are erupted over a short time, structural support for the rock above the magma chamber is gone. The ground surface then collapses into the emptied or partially emptied magma chamber, leaving a large depression at the surface (from one to dozens of kilometers in diameter). Although sometimes described as a Volcanic crater, crater, the feature is actually a type of sinkhole, as it is formed through subsidence and collapse rather than an explosion or impact. Compared to the thousands of volcanic eruptions that occur each century, the formation of a caldera is a rare event, occurring only a few times per century. Only seven caldera-forming collapses are known to have occurred between 1911 and 2016. More recently, a caldera collapse occurred at Kīlauea, Hawaii in 2018. Etymology The term ''caldera'' comes from Spanish language, S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eocene
The Eocene ( ) Epoch is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', "dawn") and (''kainós'', "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch. The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope Carbon-13, 13C in the atmosphere was exceptionally low in comparison with the more common isotope Carbon-12, 12C. The end is set at a major extinction event called the ''Grande Coupure'' (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Popigai impact structure, Siberia and in what is now ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cretaceous
The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of the entire Phanerozoic. The name is derived from the Latin ''creta'', "chalk", which is abundant in the latter half of the period. It is usually abbreviated K, for its German translation ''Kreide''. The Cretaceous was a period with a relatively warm climate, resulting in high eustatic sea levels that created numerous shallow inland seas. These oceans and seas were populated with now- extinct marine reptiles, ammonites, and rudists, while dinosaurs continued to dominate on land. The world was ice free, and forests extended to the poles. During this time, new groups of mammals and birds appeared. During the Early Cretaceous, flowering plants appeared and began to rapidly diversify, becoming the dominant group of plants across the Earth b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
