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Cerro Macá
Cerro Macá is a stratovolcano located to the north of the Aisén Fjord and to the east of the Moraleda Channel, in the Aysén del General Carlos Ibáñez del Campo Region of Chile. This glacier-covered volcano lies along the regional Liquiñe-Ofqui Fault Zone. Cerro Macá is a relatively small volcano with a volume of only . It has a summit elevation of approximately 2,300 m above sea level and features glaciers that in 2011 covered an area of . The edifice is partially eroded and a sector collapse is probably the origin of a large steep sided depression in the summit area. Pyroclastic cones with associated lava flows are found on its southwestern flank but also on the other slopes of the volcano, as far down as sea level and in the Bahia Aysen. The volcano is part of the southernmost Southern Volcanic Zone of Chile, where volcanism is caused by the subduction of the Nazca Plate. Other volcanoes in the area are Melimoyu, Mentolat, Cay and Cerro Hudson. Macá specific ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SRTM
The Shuttle Radar Topography Mission (SRTM) is an international research effort that obtained digital elevation models on a near-global scale from 56th parallel south, 56°S to 60th parallel north, 60°N, to generate the most complete high-resolution digital topographic database of Earth prior to the release of the ASTER GDEM in 2009. SRTM consisted of a specially modified radar system that flew on board the Space Shuttle Endeavour during the 11-day STS-99 mission in February 2000. The radar system was based on the older ''Spaceborne Imaging Radar, Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar'' (SIR-C/X-SAR), previously used on the Shuttle in 1994. To acquire Topography, topographic data, the SRTM payload was outfitted with two radar antennas. One antenna was located in the Shuttle's payload bay, the other – a critical change from the SIR-C/X-SAR, allowing single-pass interferometry – on the end of a 60-meter (200-foot) mast that extended from the payload bay on ... [...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] |
List Of Volcanoes In Chile
The Smithsonian Institution's Global Volcanism Program lists 105 volcanoes in Chile that have been active during the Holocene. using Chile, Chile-Peru, Chile-Bolivia and Chile-Argentina options, retrieved on 10 November 2013 The country's National Geology and Mining Service lists 90 active volcanoes. The volcanoes of the originate from the of the |
Cinder Cone
A cinder cone or scoria cone is a steep, volcanic cone, conical landform of loose pyroclastic rock, pyroclastic fragments, such as volcanic ash, clinkers, or scoria that has been built around a volcanic vent. The pyroclastic fragments are formed by explosive eruptions or lava fountains from a single, typically cylindrical, vent. As the gas-charged lava is blown violently into the air, it breaks into small fragments that solidify and fall as either cinders, clinkers, or scoria around the vent to form a cone that is often symmetrical, with slopes between 30° and 40° and a nearly circular base. Most cinder cones have a bowl-shaped volcanic crater, crater at the summit. Mechanics of eruption Cinder cones range in size from tens to hundreds of meters tall. They are composed of loose pyroclastic material (Scoria, cinder or scoria), which distinguishes them from ''spatter cones'', which are composed of agglomerated volcanic bombs. The pyroclastic material making up a cinder cone ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cochrane Lake
Cochrane may refer to: Places Australia *Cochrane railway station, Sydney, a railway station on the closed Ropes Creek railway line Canada * Cochrane, Alberta * Cochrane Lake, Alberta * Cochrane District, Ontario ** Cochrane, Ontario, a town within the above district ** Cochrane railway station, the railway station serving Cochrane town ** Unorganized North Cochrane District, an unorganized area within the above district ** Unorganized South East Cochrane District ** Unorganized South West Cochrane District * Cochrane (electoral district), former Federal electoral district, Ontario * Cochrane (provincial electoral district), former provincial electoral district in Alberta Chile * Cochrane, Chile * Cochrane Lake * Cochrane River Hong Kong * Cochrane Street Malaysia * Jalan Cochrane, Kuala Lumpur, a road in Kuala Lumpur * Cochrane MRT station, a mass rapid transit station in Kuala Lumpur United States * Cochrane, Wisconsin Organization * Cochrane (organisation), a volunt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tephra
Tephra is fragmental material produced by a Volcano, volcanic eruption regardless of composition, fragment size, or emplacement mechanism. Volcanologists also refer to airborne fragments as pyroclasts. Once clasts have fallen to the ground, they remain as tephra unless hot enough to fuse into pyroclastic rock or tuff. When a volcano explodes, it releases a variety of tephra including ash, cinders, and blocks. These layers settle on the land and, over time, sedimentation occurs incorporating these tephra layers into the geologic record. Tephrochronology is a geochronological technique that uses discrete layers of tephra—volcanic ash from a single eruption—to create a chronological framework in which Paleoecology, paleoenvironmental or Archaeology, archaeological records can be placed. Often, when a volcano explodes, biological organisms are killed and their remains are buried within the tephra layer. These fossils are later dated by scientists to determine the age of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Explosive Eruption
In volcanology, an explosive eruption is a volcanic eruption of the most violent type. A notable example is the 1980 eruption of Mount St. Helens. Such eruptions result when sufficient gas has dissolved under pressure within a Viscosity, viscous magma such that expelled lava violently froths into volcanic ash when pressure is suddenly lowered at the vent. Sometimes a lava plug will block the conduit to the summit, and when this occurs, eruptions are more violent. Explosive eruptions can expel as much as per second of rocks, dust, gas and Pyroclastic rock, pyroclastic material, averaged over the duration of eruption, that travels at several hundred meters per second as high as into the atmosphere. This cloud may subsequently collapse, creating a fast-moving pyroclastic flow of hot volcanic matter. Physics Viscous magmas cool beneath the surface before they erupt. As they do this, bubbles exsolve from the magma. Because the magma is viscous, the bubbles remain trapped in the mag ... [...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] |
Basalt
Basalt (; ) is an aphanite, aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the planetary surface, surface of a terrestrial planet, rocky planet or natural satellite, moon. More than 90% of all volcanic rock on Earth is basalt. Rapid-cooling, fine-grained basalt is chemically equivalent to slow-cooling, coarse-grained gabbro. The eruption of basalt lava is observed by geologists at about 20 volcanoes per year. Basalt is also an important rock type on other planetary bodies in the Solar System. For example, the bulk of the plains of volcanism on Venus, Venus, which cover ~80% of the surface, are basaltic; the lunar mare, lunar maria are plains of flood-basaltic lava flows; and basalt is a common rock on the surface of Mars. Molten basalt lava has a low viscosity due to its relatively low silica content (between 45% and 52%), resulting in rapidly moving lava flo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cerro Hudson
Hudson Volcano (, , or ) is the most active volcano in the southern part of the Southern Volcanic Zone of the Andes Mountains in Chile, having erupted most recently in 2011. It was formed by the subduction of the oceanic Nazca Plate under the continental South American Plate. South of Hudson is a smaller volcano, followed by a long gap without active volcanoes, then the Austral Volcanic Zone. Hudson has the form of a caldera filled with ice; the Huemules Glacier emerges from the northwestern side of the caldera. The volcano has erupted rocks ranging from basalt to rhyolite, but large parts of the caldera are formed by non-volcanic rocks. The volcano erupted numerous times in the late Pleistocene and Holocene, forming widespread tephra deposits both in the proximity of Hudson and in the wider region. Four large eruptions took place in 17,300–17,440 BP ("H0 eruption"), 7,750 BP ("H1 eruption"), 4,200 BP ("H2 eruption") and in 1991 AD ("H3 eruption"); the second is among the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cay (volcano)
Cay is a stratovolcano in the South Volcanic Zone of the Andes in Aysén del General Carlos Ibáñez del Campo Region, Chile. The volcano is located 15 km northeast of the larger Maca Volcano and about 230 km of the Chile Trench at the intersection of NW-SE and NE-SW faults of the Liquiñe-Ofqui Fault Zone. The volcano is composed from basalt and dacite and there is no evidence of Holocene activity. Below 1000m, several parasitic cones lie on the southwest flank of the volcano. See also *Geology of Chile *HidroAysén *List of volcanoes in Chile The Smithsonian Institution's Global Volcanism Program lists 105 volcanoes in Chile that have been active during the Holocene. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
