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Lazufre
Lazufre is a Quaternary volcanic dome in the central Andes, on the border between Chile and Argentina. It is part of the Central Volcanic Zone (CVZ), one of the four distinct volcanic belts of South America. The CVZ includes a number of calderas and supervolcanoes that have emplaced ignimbrites in the region. Lazufre and the majority of the Andean volcanoes formed from the subduction of the oceanic Nazca Plate under the continental South American continental lithosphere. The dome has been uplifting for the past 400,000 years and features three recent volcanoes, Lastarria, Cordón del Azufre and Cerro Bayo Complex. It may be a volcano that will in the future develop a caldera. The dome began uplifting in the late 19th century at an increasing rate, before slowing down since 2010. The uplift is among the largest in the world and has drawn attention from the scientific communities. Various explanations have been proposed, the most common being that a magma chamber is filling up. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cordón Del Azufre
Cordón del Azufre is a small, inactive complex volcano located in the Central Andes, at the border of Argentina and Chile. Geology and geomorphology The volcano lies at the border between Argentina and Chile and contains a series of craters and lava flows covering a surface area of . A western component with four craters aligned in a north–south direction on a ridge forms the oldest part. Numerous monogenetic volcanoes and stratovolcanoes developed on it and buried most of its central crater under lava flows. A pile of lava flows covers an area of on the eastern side. The eastern component is formed by lava flows and craters in Argentina, and the youngest part la Moyra volcano in the western component generated a lava flow that advanced westwards. Weakly porphyritic andesite and dacite form the rocks of the volcano. Lava flows of the eastern component have been dated to be 600,000 years old. No activity, including fumarolic activity, has been recorded at Cordón del Azu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lastarria
Lastarria is a high stratovolcano that lies on the border between Chile and Argentina. It is remote and the surroundings are uninhabited but can be reached through an unpaved road. The volcano is part of the Central Volcanic Zone, one of the four segments of the volcanic arc of the Andes. Over a thousand volcanoes - of which about 50 are active - lie in this over long chain of volcanoes, which is generatedby subduction of the Nazca Plate beneath the South American Plate. The volcano is constituted by two volcanic edifices that form a ridge, and one subsidiary lava flow field southwest of the main volcanoes. The main edifice features several aligned craters that form a line. There is no recorded eruptive activity, but the volcano displays vigorous fumarolic activity on its northern side and within the craters. It is located on top of older volcanic rocks and features both andesite and dacite. Lastarria produced a large landslide deposit when part of its southeastern flank colla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Los Colorados (caldera)
Los Colorados is the name of a caldera in Chile. It is part of the Central Volcanic Zone of the Andes. The caldera has a diameter of and was formed 9.8 million years ago within a basement consisting of Paleozoic rocks, Miocene ignimbrites and older volcanoes. The caldera is the source of the Los Colorados ignimbrite, which was erupted 7.9-7.76 million years ago. This ignimbrite is formed by highly welded dacite, is rich in pumice and has a dark pink colour. Quartz, sherds are also widespread. This ignimbrite covers a surface area of , spilling into Argentina. Part of the Los Colorados ignimbrite has been identified at the Laguna Amarga caldera. After the formation of the caldera, between 6.9 and 6.8 million years ago the Abra Grande, Aguas Calientes and Río Grande stratovolcanoes grew in the caldera. Lava flows from Cerro Bayo and Cordón del Azufre have invaded the northwestern sector of the caldera. The Los Colorados caldera coalesces with the Lazufre structure along the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quaternary
The Quaternary ( ) is the current and most recent of the three periods of the Cenozoic Era in the geologic time scale of the International Commission on Stratigraphy (ICS). It follows the Neogene Period and spans from 2.58 million years ago to the present. The Quaternary Period is divided into two epochs: the Pleistocene (2.58 million years ago to 11.7 thousand years ago) and the Holocene (11.7 thousand years ago to today, although a third epoch, the Anthropocene, has been proposed but is not yet officially recognised by the ICS). The Quaternary Period is typically defined by the cyclic growth and decay of continental ice sheets related to the Milankovitch cycles and the associated climate and environmental changes that they caused. Research history In 1759 Giovanni Arduino proposed that the geological strata of northern Italy could be divided into four successive formations or "orders" ( it, quattro ordini). The term "quaternary" was introduced by Jules Desnoye ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cerro Bayo
Cerro Bayo is a mountain of the Andes range located 9 km from the town Villa La Angostura, Neuquén Province, Argentina, within the Valdivian temperate rain forests, in an area with numerous lakes. The mountain hosts a ski area with 25 runs and 16 lifts. In 2007, the 2nd South American Ski Mountaineering Championship was carried out on the Cerro Bayo. See also * Cerro Castor * Cerro Catedral * Chapelco * Las Leñas Las Leñas is a ski resort in Argentina, located in the western part of Mendoza Province. It has reliable powder snow and climate for extreme and off-piste skiing. Construction of the ski center began January 1983, and by July 1983, it opened wi ... * List of ski areas and resorts in South America References {{DEFAULTSORT:Bayo, Cerro Landforms of Neuquén Province Mountains of Argentina Ski areas and resorts in Argentina ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subducts
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 dens ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geothermal Activity
Geothermal activity is a group of natural heat transfer processes, occurring on Earth's surface, caused by the presence of excess heat in the subsurface of the affected area. Geothermal activity can manifest itself in a variety of different phenomena, including, among others, elevated surface temperatures, various forms of hydrothermal activity, and the presence of fumaroles that emit hot volcanic gases. Background physics Geothermal activity mostly appears in volcanic provinces, in some cases it can be caused by underground fires or by large deposits of radioactive elements. Other sources of internal heating can be gravitational differentiation of substances, tidal friction, metamorphism, or phase transitions. The release of heat to the surface occurs either in the form of a conductive heat flow, or in the form of convective heat transfer by groundwater or gases. Geothermal activity Fumaroles and vents Fumaroles, or volcanic vents, are holes in the ground from which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cerro Escorial
Cerro Escorial is a stratovolcano at the border of Argentina and Chile. It is part of the Corrida de Cori volcanic group and its youngest member. A well-preserved crater forms its summit area. Lava flows are found on the Chilean and smaller ones on the Argentinian side, the former reaching as far as from the volcano. One of these is dated 342,000 years ago by argon-argon dating. Off the western coast of South America, the Nazca Plate subducts beneath the South America Plate. This process has given rise to the Andes mountain chain and the Altiplano- Puna high plateau, which formed through shortening of the crust that lasted until 1 million years ago. Cerro Escorial rises from the Puna, which is dissected at Cerro Escorial by the Archibarca lineament; it is a strike-slip fault that has facilitated the ascent of magma. Andesite lavas were erupted during the Miocene and Pliocene. Hydrothermal alteration has affected an area from the crater. A Plinian eruption on Escorial w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corrida De Cori
Corrida de Cori is a mountain range in Argentina and Chile. It consists of several aligned volcanoes, including Cerro Escorial, which exceed in elevation. The range, together with several local volcanoes, forms an alignment that may be controlled by a fault system. The volcanoes erupted mainly andesite and basaltic andesite, they were active in the Plio-Pleistocene with the most recent activity occurring at Cerro Escorial and at a cinder cone east of the range. There are two mines in the area, with a weather station nearby. Geography and geomorphology Corrida de Cori a range of Plio-Pleistocene volcanoes of small to medium dimensions. It is located in the Puna of South America, Salta province of Argentina and the Antofagasta Region of Chile. The boundary between the two countries was defined to run over this mountain range. Cerro Escorial is part of this range, Cerro Negro () and Cerro Corrida de Cori ( ) are other summits, Lastarria may also be linked. The Cerro Negro-C ... [...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 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 gas bubbles. Magma is produced by melting of the mantle or the crust in various tectonic settings, which on Earth include subduction zones, continental rift zones, mid-ocean ridges and hotspots. Mantle and crustal melts migrate upwards through the crust where they are thought to be stored in magma chambers or trans-crustal crystal-rich mush zones. During magma's storage in the crust, its composition may be modified by fractional crystallization, contamination with crustal melts, magma mixing, and degassing. Following its ascent through the crust, magma may feed a volcano and be extruded as lava, or it may solidify underground to form an intrusion, such as a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basaltic Andesite
Basaltic andesite is a volcanic rock that is intermediate in composition between basalt and andesite. It is composed predominantly of augite and plagioclase. Basaltic andesite can be found in volcanoes around the world, including in Central America and the Andes of South America. Description Basaltic andesite is a fine-grained (aphanitic) igneous rock that is moderately low in silica and low in alkali metal oxides. It is not separately defined in the QAPF classification, which is based on the relative percentages of quartz, alkali feldspar, plagioclase feldspar, and feldspathoids, but would fall in the basalt-andesite field. This corresponds to rock in which feldspathoid makes up less than 10% and quartz less than 20% of the total QAPF fraction, and in which at least 65% of the feldspar is plagioclase. Basaltic andesite would be further distinguished from basalt and andesite by a silica content between 52% and 57%. Although classification by mineral content is preferred by the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
