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Volcanoes Of Chile
Volcanism of Chile is a continuous volcanic process that has a strong influence on Chilean landscape, geology, economy and society. Volcanism constantly renews the Chilean landscape with lava flows, lava plateaus, lava domes, cinder cones, stratovolcanoes, shield volcanoes, submarine volcanoes, calderas, diatremes, and maars. Volcanism in Chile as well as in other parts of the world is also associated with multiple natural hazards such as lahars, earthquakes, pyroclastic flows, toxic gases and ash. Continental Chile has a high concentration of active volcanoes due to its location along the Peru–Chile Trench, a subduction zone where the Nazca and Antarctic Plates are driven beneath the South American Plate. Chile has been subject to volcanism since at least late Paleozoic when subduction along the western margin of South America began. Easter Island, Juan Fernández Islands and other oceanic islands of Chile are extinct volcanoes created by hotspots. The ''Servicio Nacional de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chaitén
Chaitén (, ) is a Chilean List of towns in Chile, town, Communes of Chile, commune and former capital of the Palena Province in Los Lagos Region. The town is north of the mouth of Yelcho River, on the east coast of the Gulf of Corcovado. The town is strategically close to the northern end of the Carretera Austral, where the highway goes inland. The Desertores Islands are part of the commune. Evacuation The town was evacuated in May 2008 when the Chaitén (volcano), Chaitén volcano erupted for the first time in more than 9,000 years. The eruption, which commenced May 2, became more violent on May 5, throwing up a high plume of ash and sulfurous steam that rose to , from which ashfall drifted across Patagonia and over the Atlantic Ocean. During 2005 small earthquakes occurred below Chaitén and the nearby Liquiñe-Ofqui Fault, Liquiñe-Ofqui Fault Zone. The town was completely flooded on May 12, 2008, after a lahar caused the banks of the Blanco River to overflow about on eac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lahar
A lahar (, from ) is a violent type of mudflow or debris flow composed of a slurry of Pyroclastic rock, pyroclastic material, rocky debris and water. The material flows down from a volcano, typically along a valley, river valley. Lahars are often extremely destructive and deadly; they can flow tens of metres per second, they have been known to be up to deep, and large flows tend to destroy any structures in their path. Notable lahars include those at Mount Pinatubo in the Philippines and Nevado del Ruiz in Colombia, the latter of which killed more than 20,000 people in the Armero tragedy. Etymology The word ''lahar'' is of Javanese language, Javanese origin. Berend George Escher introduced it as a geological term in 1922. Description The word ''lahar'' is a general term for a flowing mixture of water and pyroclastic debris. It does not refer to a particular rheology or sediment concentration. Lahars can occur as normal stream flows (sediment concentration of less than 30%), ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South America
South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion of the Americas. South America is bordered on the west by the Pacific Ocean, on the north and east by the Atlantic Ocean, and to the south by the Drake Passage; North America and the Caribbean Sea lie to the northwest. The continent includes twelve sovereign states: Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Guyana, Paraguay, Peru, Suriname, Uruguay, and Venezuela; two dependent territory, dependent territories: the Falkland Islands and South Georgia and the South Sandwich Islands; and one administrative division, internal territory: French Guiana. The Dutch Caribbean ABC islands (Leeward Antilles), ABC islands (Aruba, Bonaire, and Curaçao) and Trinidad and Tobago are geologically located on the South-American continental shel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleozoic
The Paleozoic ( , , ; or Palaeozoic) Era is the first of three Era (geology), geological eras of the Phanerozoic Eon. Beginning 538.8 million years ago (Ma), it succeeds the Neoproterozoic (the last era of the Proterozoic Eon) and ends 251.9 Ma at the start of the Mesozoic Era. The Paleozoic is subdivided into six period (geology), geologic periods (from oldest to youngest), Cambrian, Ordovician, Silurian, Devonian, Carboniferous and Permian. Some geological timescales divide the Paleozoic informally into early and late sub-eras: the Early Paleozoic consisting of the Cambrian, Ordovician and Silurian; the Late Paleozoic consisting of the Devonian, Carboniferous and Permian. The name ''Paleozoic'' was first used by Adam Sedgwick (1785–1873) in 1838 to describe the Cambrian and Ordovician periods. It was redefined by John Phillips (geologist), John Phillips (1800–1874) in 1840 to cover the Cambrian to Permian periods. It is derived from the Ancient Greek, Greek ''palaiós'' (πΠ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South American Plate
The South American plate is a major tectonic plate which includes the continent of South America as well as a sizable region of the Atlantic Ocean seabed extending eastward to the African plate, with which it forms the southern part of the Mid-Atlantic Ridge. The easterly edge is a divergent boundary with the African plate; the southerly edge is a complex boundary with the Antarctic plate, the Scotia plate, and the Sandwich Plate; the westerly edge is a convergent boundary with the subducting Nazca plate; and the northerly edge is a boundary with the Caribbean plate and the oceanic crust of the North American plate. At the Chile triple junction, near the west coast of the Taitao– Tres Montes Peninsula, an oceanic ridge known as the Chile Rise is actively subducting under the South American plate. Geological research suggests that the South American plate is moving west away from the Mid-Atlantic Ridge: "Parts of the plate boundaries consisting of alternations of re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nazca Plate
The Nazca plate or Nasca plate, named after the Nazca region of southern Peru, is an oceanic list of tectonic plates, tectonic plate in the eastern Pacific Ocean basin off the west coast of South America. The ongoing subduction, along the Peru–Chile Trench, of the Nazca plate under the South American plate is largely responsible for the Andes, Andean orogeny. The Nazca plate is bounded on the west by the Pacific plate and to the south by the Antarctic plate through the East Pacific Rise and the Chile Rise, respectively. The movement of the Nazca plate over several Hotspot (geology), hotspots has created some volcanic islands as well as east–west running seamount chains that subduct under South America. Nazca is a relatively young plate in terms of the age of its rocks and its existence as an independent plate, having been formed from the breakup of the Farallon plate about 23 million years ago. The oldest rocks of the plate are about 50 million years old. Boundaries ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subduction
Subduction is a geological process in which the oceanic lithosphere and some continental lithosphere is recycled into the Earth's mantle at the convergent boundaries between tectonic plates. Where one tectonic plate converges with a second plate, the heavier plate dives beneath the other 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 rates of convergence as high as 11 cm/year. Subduction is possible because the cold and rigid oceanic lithosphere is slightly denser than the underlying asthenosphere, the hot, ductile layer in the upper mantle. Once initiated, stable subduction is driven mostly by the negative buoyancy of the dense subducting lithosphere. The down-going slab sinks into the mantle largely under its own ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peru–Chile Trench
The Peru–Chile Trench, also known as the Atacama Trench, is an oceanic trench in the eastern Pacific Ocean, about off the coast of Peru and Chile. It reaches a maximum depth of below sea level in Richards Deep () and is approximately long; its mean width is and it covers an expanse of some . The trench delineates the boundary between the subduction, subducting Nazca plate and the overriding South American plate. Geology The trench is a result of a convergent plate boundary, where the eastern edge of the oceanic Nazca plate is being subduction, subducted beneath the continental South American plate. The trench is also a part of the Chile triple junction, an unusual junction that consists of a Mid-ocean ridge, mid-oceanic ridge and the Chile Rise being subducted under the South American plate at the Peru–Chile Trench. Two seamount ridges within the Nazca plate enter the subduction zone along this trench: the Nazca Ridge and the Juan Fernández Ridge. From the Chile triple ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcano
A volcano is commonly defined as a vent or fissure 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 because most of Earth's plate boundaries are underwater, most volcanoes 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 resulting from divergent tectonic activity are usually non-explosive whereas those resulting from convergent tectonic activity cause violent eruptions."Mid-ocean ridge tectonics, volcanism and geomorphology." Geology 26, no. 455 (2001): 458. https://macdonald.faculty.geol.ucsb.edu/papers/Macdonald%20Mid-Ocean%20Ridge%20Tectonics.pdf Volcanoes can also form where there is str ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Continental Chile
Continental Chile is the name given to the Chilean territory located on the continental shelf of South America. This term serves to distinguish the South American area from the insular territories, known as Insular Chile, as from the Chilean Antarctica (Chilean Antarctic Territory). The existence of this three areas of effective or claimed Chilean sovereignty is what supports the existing tricontinental principle in this country. The term "Continental Chile Time" specifies the time zone of most of Continental Chile, Juan Fernández Islands and Desventuradas Islands, as UTC−4 in winter and UTC−3 in summer. However, the regions of Aysén and Magallanes and Chilean Antarctica use UTC−3 all year. Easter Island and Isla Salas y Gómez, both in Polynesia, use UTC−6 in winter and UTC−5 in summer. Continental Chile has a surface of 756,770 km2, representing 99.976% of the total surface of the country under effective administration. However, considering the claim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanic Ash
Volcanic ash consists of fragments of rock, mineral crystals, and volcanic glass, produced during volcanic eruptions and measuring less than 2 mm (0.079 inches) in diameter. The term volcanic ash is also often loosely used to refer to all explosive eruption products (correctly referred to as '' tephra''), including particles larger than 2 mm. Volcanic ash is formed during explosive volcanic eruptions when dissolved gases in magma expand and escape violently into the atmosphere. The force of the gases shatters the magma and propels it into the atmosphere where it solidifies into fragments of volcanic rock and glass. Ash is also produced when magma comes into contact with water during phreatomagmatic eruptions, causing the water to explosively flash to steam leading to shattering of magma. Once in the air, ash is transported by wind up to thousands of kilometres away. Due to its wide dispersal, ash can have a number of impacts on society, including animal a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
