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Miravalles Volcano
The Miravalles Volcano is an andesitic stratovolcano in Costa Rica. The caldera was formed during several major explosive eruptions that produced voluminous dacitic-rhyolitic pyroclastic flows A pyroclastic flow (also known as a pyroclastic density current or a pyroclastic cloud) is a fast-moving current of hot gas and volcanic matter (collectively known as tephra) that flows along the ground away from a volcano at average speeds of b ... between about 1.5 and 0.6 million years ago. The only reported historical eruptive activity was a small steam explosion on the SW flank in 1946. High heat flow remains, and Miravalles is the site of the largest developed geothermal field in Costa Rica. The Miravalles Volcano reaches an elevation of and is the highest mountain in the Guanacaste Mountains. The heat from the volcano also helps power a geothermal energy plant at Las Hornillas, which is run by the Institute of Electricity. References Active volcanoes Stratovol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Volcanoes In Costa Rica ...
This is a list of active and extinct volcanoes in Costa Rica. See also * List of lakes in Costa Rica * Central America Volcanic Arc * List of volcanoes in El Salvador * List of volcanoes in Guatemala * List of volcanoes in Honduras * List of volcanoes in Nicaragua * List of volcanoes in Panama References External links Vulcanología Observatorio Vulcanológico y Sismológico de Costa Rica (OVSICORI).Volcanes de Costa Rica I {{Central American volcanoes Costa Rica Volcanoes 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Costa Rica
Costa Rica (, ; ; literally "Rich Coast"), officially the Republic of Costa Rica ( es, República de Costa Rica), is a country in the Central American region of North America, bordered by Nicaragua to the north, the Caribbean Sea to the northeast, Panama to the southeast, the Pacific Ocean to the southwest, and Maritime boundary, maritime border with Ecuador to the south of Cocos Island. It has a population of around five million in a land area of . An estimated 333,980 people live in the capital and largest city, San José, Costa Rica, San José, with around two million people in the surrounding metropolitan area. The sovereign state is a Unitary state, unitary Presidential system, presidential Constitution of Costa Rica, constitutional republic. It has a long-standing and stable democracy and a highly educated workforce. The country spends roughly 6.9% of its budget (2016) on education, compared to a global average of 4.4%. Its economy, once heavily dependent on agricultu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cordillera De Guanacaste
The Cordillera de Guanacaste, also called Guanacaste Cordillera, are a volcanic mountain range in northern Costa Rica near the border with Nicaragua. The mountain range stretches 110 km from northwest to the southeast and contains mostly complex stratovolcanoes. The range forms part of the southern region of the Continental Divide, with the highest peak is the stratovolcano Miravalles at 2,028 m. Rivers flowing from the range drain into the Caribbean Sea (Guacalito, Zapote) and the Pacific Ocean (Blanco, Tenorio, Martirio, Corobiá and San Lorenzo). Protected areas located in the mountain range include Guanacaste National Park established in July 1991 and Area de Conservación Guanacaste World Heritage Site inscribed by UNESCO as a World Heritage Site in December 1999. The range contains areas of ecological significance, as the Miravalles Forest Reserve, hills and canyons that can be seen from the lowlands of Guanacaste, areas rich with epiphytes, ferns and palms; and are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stratovolcano
A stratovolcano, also known as a composite volcano, is a conical volcano built up by many layers (strata) of hardened lava and tephra. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile with a summit crater and periodic intervals of explosive eruptions and effusive eruptions, although some have collapsed summit craters called calderas. The lava flowing from stratovolcanoes typically cools and hardens before spreading far, due to high viscosity. The magma forming this lava is often felsic, having high-to-intermediate levels of silica (as in rhyolite, dacite, or andesite), with lesser amounts of less-viscous mafic magma. Extensive felsic lava flows are uncommon, but have travelled as far as . Stratovolcanoes are sometimes called composite volcanoes because of their composite stratified structure, built up from sequential outpourings of erupted materials. They are among the most common types of volcanoes, in contrast to the less common shield volca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Andesitic
Andesite () is a volcanic rock of intermediate composition. In a general sense, it is the intermediate type between silica-poor basalt and silica-rich rhyolite. It is fine-grained (aphanitic) to porphyritic in texture, and is composed predominantly of sodium-rich plagioclase plus pyroxene or hornblende. Andesite is the extrusive equivalent of plutonic diorite. Characteristic of subduction zones, andesite represents the dominant rock type in island arcs. The average composition of the continental crust is andesitic. Along with basalts, andesites are a component of the Martian crust. The name ''andesite'' is derived from the Andes mountain range, where this rock type is found in abundance. It was first applied by Christian Leopold von Buch in 1826. Description Andesite is an aphanitic (fine-grained) igneous rock that is intermediate in its content of silica and low in alkali metals. It has less than 20% quartz and 10% feldspathoid by volume, with at least 65% of the feldsp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stratovolcano
A stratovolcano, also known as a composite volcano, is a conical volcano built up by many layers (strata) of hardened lava and tephra. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile with a summit crater and periodic intervals of explosive eruptions and effusive eruptions, although some have collapsed summit craters called calderas. The lava flowing from stratovolcanoes typically cools and hardens before spreading far, due to high viscosity. The magma forming this lava is often felsic, having high-to-intermediate levels of silica (as in rhyolite, dacite, or andesite), with lesser amounts of less-viscous mafic magma. Extensive felsic lava flows are uncommon, but have travelled as far as . Stratovolcanoes are sometimes called composite volcanoes because of their composite stratified structure, built up from sequential outpourings of erupted materials. They are among the most common types of volcanoes, in contrast to the less common shield volca ... [...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] |
Pyroclastic Flows
A pyroclastic flow (also known as a pyroclastic density current or a pyroclastic cloud) is a fast-moving current of hot gas and volcanic matter (collectively known as tephra) that flows along the ground away from a volcano at average speeds of but is capable of reaching speeds up to . The gases and tephra can reach temperatures of about . Pyroclastic flows are the most deadly of all volcanic hazards and are produced as a result of certain explosive eruptions; they normally touch the ground and hurtle downhill, or spread laterally under gravity. Their speed depends upon the density of the current, the volcanic output rate, and the gradient of the slope. Origin of term The word ''pyroclast'' is derived from the Greek (''pýr''), meaning "fire", and (''klastós''), meaning "broken in pieces". A name for pyroclastic flows which glow red in the dark is (French, "burning cloud"); this was notably used to describe the disastrous 1902 eruption of Mount Pelée on Martinique, a Frenc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geothermal (geology)
Geothermal gradient is the rate of temperature change with respect to increasing depth in Earth's interior. As a general rule, the crust temperature rises with depth due to the heat flow from the much hotter mantle; away from tectonic plate boundaries, temperature rises in about 25–30 °C/km (72–87 °F/mi) of depth near the surface in most of the world. However, in some cases the temperature may drop with increasing depth, especially near the surface, a phenomenon known as ''inverse'' or ''negative'' geothermal gradient. The effects of weather, sun, and season only reach a depth of approximately 10-20 metres. Strictly speaking, ''geo''-thermal necessarily refers to Earth but the concept may be applied to other planets. In SI units, the geothermal gradient is expressed as °C/km, K/km, or mK/m. These are all equivalent. Earth's internal heat comes from a combination of residual heat from planetary accretion, heat produced through radioactive decay, latent hea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geothermal Energy
Geothermal energy is the thermal energy in the Earth's crust which originates from the formation of the planet and from radioactive decay of materials in currently uncertain but possibly roughly equal proportions. The high temperature and pressure in Earth's interior cause some rock to melt and solid mantle to behave plastically. This results in parts of the mantle convecting upward since it is lighter than the surrounding rock. Temperatures at the core–mantle boundary can reach over 4000 °C (7200 °F). Geothermal heating, using water from hot springs, for example, has been used for bathing since Paleolithic times and for space heating since ancient Roman times. More recently geothermal power, the term used for generation of electricity from geothermal energy, has gained in importance. It is estimated that the earth's geothermal resources are theoretically more than adequate to supply humanity's energy needs, although only a very small fraction is currently being ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Active Volcanoes
An active volcano is a volcano which is either erupting or is likely to erupt in the future. An active volcano which is not currently erupting is known as a dormant volcano. Overview Tlocene Epoch. Most volcanoes are situated on the Pacific Ring of Fire. An estimated 500 million people live near active volcanoes. ''Historical time'' (or recorded history) is another timeframe for ''active''. However, the span of recorded history differs from region to region. In China and the Mediterranean, it reaches back nearly 3,000 years, but in the Pacific Northwest of the United States and Canada, it reaches back less than 300 years, and in Hawaii and New Zealand it is only around 200 years. The incomplete ''Catalogue of the Active Volcanoes of the World'', published in parts between 1951 and 1975 by the International Association of Volcanology, uses this definition, by which there are more than 500 active volcanoes. , the Smithsonian Global Volcanism Program recognizes 560 volcanoes with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stratovolcanoes Of Costa Rica
A stratovolcano, also known as a composite volcano, is a conical volcano built up by many layers (strata) of hardened lava and tephra. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile with a summit crater and periodic intervals of explosive eruptions and effusive eruptions, although some have collapsed summit craters called calderas. The lava flowing from stratovolcanoes typically cools and hardens before spreading far, due to high viscosity. The magma forming this lava is often felsic, having high-to-intermediate levels of silica (as in rhyolite, dacite, or andesite), with lesser amounts of less-viscous mafic magma. Extensive felsic lava flows are uncommon, but have travelled as far as . Stratovolcanoes are sometimes called composite volcanoes because of their composite stratified structure, built up from sequential outpourings of erupted materials. They are among the most common types of volcanoes, in contrast to the less common shield volcanoes. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
