Instruct: Given a question, retrieve passages that answer the question.
Query: How long is the Central Volcanic Zone of the Andes?
The South Volcanic Zone (SVZ) extends roughly from Central Chile's Andes at the latitude of Santiago, at ca. 33°S, to Cerro Arenales in Aysén Region at ca. 46°S, a distance of well over 870 mi (1,400 km). The arc has formed due to subduction of the Nazca Plate under the South American Plate along the Peru–Chile Trench. The northern boundary of the SVZ is marked by the flat-slab subduction of the Juan Fernández Ridge, which is believed to have produced a volcanic gap called the "Pampean flat-slab segment" in the Norte Chico region since the late Miocene. The southern end of the SVZ is marked by the Chile Triple Junction where the Chile Rise subducts under South America at the Taitao Peninsula giving origin to the "Patagonian Volcanic Gap". Further south lies the Austral Volcanic Zone.
Ambato lies in the main valley of the Central Cordillera, the highest of the Andean mountain ranges. The city itself is carved into the side of Cerro Casigana, the mountain that dominates the north end of the city. From Ambato, it is possible to see many snow-capped volcanoes including Cotopaxi, Tungurahua, Carihuairazo, and the largest mountain in Ecuador, Chimborazo. Tungurahua lies about 40 kilometers to the southeast. The threat of eruption from the volcano is constant. On May 16, 2006, Tungurahua erupted, covering the city with a thick layer of ash.
Standing at a height of 2,920 meters (9,580 feet) above sea level, the Tequila Volcano, or "Volcán de Tequila" is a Stratovolcano located near Tequila, Jalisco, in Mexico. Stratovolcanoes, also referred to as Composite Volcanoes, are the "iconically" conical-shaped volcanoes, found most commonly along subduction zones. Stratovolcanoes are composed of steeply dipping layers of lava, hardened ash, and other material that erupted from the main vent such as tephra and pumice. Commonly higher than 2500 meters above sea-level, Stratovolcanoes have gentle lower slopes which gradually become steeper the higher you get with a relatively small summit crater. Due to their eruptions, Stratovolcanoes have several distinct variations giving some a specific feature such as calderas and amphitheaters.
The Middle America Trench is a major subduction zone, an oceanic trench in the eastern Pacific Ocean off the southwestern coast of Middle America, stretching from central Mexico to Costa Rica. The trench is 1,700 miles (2,750 km) long and is 21,880 feet (6,669 m) at its deepest point.
The trench is the boundary between the Rivera, Cocos, and Nazca plates on one side and the North American and Caribbean plates on the other. It is the 18th-deepest trench in the world. Many large earthquakes have occurred in the area of the Middle America Trench.
The Andes mountains form the most populated region of Colombia and contain the majority of the country's urban centers. They were also the location of the most significant pre-Columbian indigenous settlements. Beyond the Colombian Massif in the south-western departments of Cauca and Nariño, the Colombian Andes divide into three branches known as "cordilleras" (from the Spanish for "mountain range"): the West Andes run adjacent to the Pacific coast and is home to the city of Cali. The Central Andes run up the center of the country between the Cauca and Magdalena river valleys (to the west and east respectively) and includes the cities of Medellín, Manizales and Pereira. The East Andes extend northeast towards the Guajira Peninsula, and includes the cities of Bogotá, Bucaramanga and Cúcuta.
The peak of Chimborazo is the farthest point from the center of the Earth. This is due to the Earth bulging out at the equator and Chimborazo being located just one degree south of the equator. Mount Everest is 28° north of the equator. Thus Chimborazo is 2.1 kilometres farther from the Earth's center than Everest. Chimborazo is 73.5 metres higher than the highest mountain in North America. Chimborazo is often associated with the nearby volcano Cotopaxi, although the two volcanoes have completely different structures.
The summit of Mount Everest is higher above sea level, but the summit of Chimborazo is widely reported to be the farthest point on the surface from Earth's center, with Huascarán a very close second. The summit of the Chimborazo is the fixed point on Earth that has the utmost distance from the center – because of the oblate spheroid shape of the planet Earth, which is "thicker" around the Equator than measured around the poles. Chimborazo is one degree south of the Equator and the Earth's diameter at the Equator is greater than at the latitude of Everest ( above sea level), nearly 27.6° north, with sea level also elevated. Despite being lower in elevation above sea level, it is from the Earth's center, farther than the summit of Everest ( from the Earth's center). However, by height above sea level, Chimborazo is not the highest peak of the Andes.
A supervolcano usually has a large caldera and can produce devastation on an enormous, sometimes continental, scale. Such volcanoes are able to severely cool global temperatures for many years after the eruption due to the huge volumes of sulfur and ash released into the atmosphere. They are the most dangerous type of volcano. Examples include Yellowstone Caldera in Yellowstone National Park and Valles Caldera in New Mexico (both western United States); Lake Taupo in New Zealand; Lake Toba in Sumatra, Indonesia; and Ngorongoro Crater in Tanzania. Because of the enormous area they may cover, supervolcanoes are hard to identify centuries after an eruption. Similarly, large igneous provinces are also considered supervolcanoes because of the vast amount of basalt lava erupted (even though the lava flow is non-explosive).
Aconcagua (), with a summit elevation of , is the highest mountain in both the Southern and Western Hemispheres. It is located in the Andes mountain range, in the Mendoza Province, Argentina, and lies northwest of its capital, the city of Mendoza, about from San Juan Province and from the international border with Chile. The mountain itself lies entirely within Argentina, immediately east of Argentina's border with Chile. Its nearest higher neighbor is Tirich Mir in the Hindu Kush, away. It is one of the Seven Summits.
The Colca Canyon, twice as deep as the Grand Canyon in the United States, is situated in the province of Caylloma. The Cotahuasi Canyon is in the La Union Province. Colca Valley provides incredible close-up views of majestic Andean condors soaring in their natural habitat. Cotahuasi, at , is thought to be the deepest canyon in the world. Both canyons offer spectacular scenery and villages as yet unaffected by the modern world.
Ecuador is a country in western South America, bordering the Pacific Ocean at the Equator, for which the country is named. Ecuador encompasses a wide range of natural formations and climates, from the desert-like southern coast to the snowcapped peaks of the Andes mountain range to the plains of the Amazon Basin. Cotopaxi in Ecuador is one of the world's highest active volcanos. It also has a large series of rivers that follow the southern border and spill into the northwest area of Peru.
Indonesia, one of the most seismically active places in the world, hosts hundreds of islands, many with volcanoes. It is an island arc, composed by a subduction zone (in the Sunda Trench) and islands. Unlike most subduction zones, the Sunda Trench is parallel to the chain of islands to which it corresponds, creating strike-slip faulting. Indonesia itself is surrounded by multiple tectonic plates – namely the Pacific, the Southeast Asia lithospheric, and the Indo-Australian Plates – causing it to be a so-called hotspot for both seismic and volcanic activity. The epicenter was in Papua Province, in the Irian Jaya Province. The orientation and type of faulting is uncertain, due to a poorly constrained focal mechanism but is thought to have been a reverse fault.
Group C
In South America, a phenomenon known as the El Nino Oscillation Cycle, between floods and drought on the Pacific Coast has made as much as a 35% difference in Global yields of wheat and grain.
Lahars (from a Javanese term for volcanic mudflows) are mixtures of volcanic debris and water. Lahars usually come from two sources: rainfall or the melting of snow and ice by hot volcanic elements, such as lava. Depending on the proportion and temperature of water to volcanic material, lahars can range from thick, gooey flows that have the consistency of wet concrete to fast-flowing, soupy floods. As lahars flow down the steep sides of stratovolcanoes, they have the strength and speed to flatten or drown everything in their paths. Hot ashes, lava flows and pyroclastic surges ejected during 1985 eruption of Nevado del Ruiz in Colombia melted snow and ice atop the high Andean volcano. The ensuing lahar flooded the city of Armero and nearby settlements, killing 25,000 people.
The largest mountain ranges are the Andes and Rocky Mountains. The Sierra Nevada and the Cascade Range reach similar altitudes as the Rocky Mountains, but are significantly smaller. In North America, the greatest number of fourteeners are in the United States, and more specifically in the U.S. state of Colorado. The highest peaks of the Americas are located in the Andes, with Aconcagua of Argentina being the highest; in North America Denali (Mount McKinley) in the U.S. state of Alaska is the tallest.
Group D
Canaima National Park is spread over 30,000 square kilometers to the border with Guayana Esequiba reclamation area now Guyana and Brazil, for its size is considered the world's sixth largest national park. About 65% of the park is occupied by rock plateaus called tepuis. These are a unique biological environment, also presenting a great geological interest. Its steep cliffs and waterfalls (including Angel Falls, which is the highest waterfall of the world, 1,002 m) are spectacular sceneries.Venezuela has many beaches of calm waters and for extreme sports. Besides those already mentioned, most famous sites for its beauty its are:South of Venezuela in the states Bolivar, Amazonas and Delta Amacuro begins the Amazon rainforest, the largest rainforest and the largest nature reserve in the world. This area of the country has great tourism value, because there is the Angel Falls, the highest waterfall of the world; savannah, rivers, forests and tepuis form a ecotourism that has not yet been truly exploited, it is necessary that the national government to promote plans to turn over this Venezuelan soil an essential point for ecotourism in this part of the world.
In recorded history, explosive eruptions at subduction zone (convergent-boundary) volcanoes have posed the greatest hazard to civilizations. Subduction-zone stratovolcanoes, such as Mount St. Helens, Mount Etna and Mount Pinatubo, typically erupt with explosive force: the magma is too stiff to allow easy escape of volcanic gases. As a consequence, the tremendous internal pressures of the trapped volcanic gases remain and intermingle in the pasty magma. Following the breaching of the vent and the opening of the crater, the magma degasses explosively. The magma and gases blast out with high speed and full force.
The Tucura Fault is located in the northern part of the Central Ranges of the Colombian Andes, west of the Romeral Fault System. It extends from the Paderisco River in the south to the Sinú Valley in the north, where it crosses the Serranía de Abibe. The fault crosscuts middle and upper Tertiary folded marine sedimentary rocks and Quaternary alluvial deposits. The fault controls drainage, forms linear ridges, topographic lineaments, and fault scarps about high on Quaternary terraces south of the town of Dabeiba, Antioquia. There are strong linear features on the right margin of the Esmeralda and Sinú Rivers; these include fault saddles and slight slope changes in alluvial terraces. Tertiary rock units are thrust over Quaternary deposits and striae are found on the shear planes.
In Ecuador, the National Polytechnic University department looks to the monitoring of the volcanic activity in this andean nation.
Cotopaxi is a stratovolcano in the Andes Mountains, located about south of Quito, Ecuador, South America. It is the second highest summit in the country, reaching a height of . Some consider it the world's highest active volcano, while others give this status to the considerably higher Llullaillaco, which most recently erupted in 1877 and is one of Ecuador's most active volcanoes. Since 1738, Cotopaxi has erupted more than 50 times, resulting in the creation of numerous valleys formed by lahars (mudflows) around the volcano.
Volcanism along the Andes occurs in four separate belts, the Northern Volcanic Zone, the Central Volcanic Zone, the Southern Volcanic Zone and the Austral Volcanic Zone. Tocorpuri is part of the Central Volcanic Zone, which in this region is characterized by an ignimbrite formation and individual volcanoes, with compositions ranging from andesite over dacite to rhyolite. Both these formations are emplaced on a Cretaceous-Miocene basement formed by sediments and volcanic rocks, which overlay Precambrian-Paleozoic layers. Aside from stratovolcanoes which are lined up in the Western Cordillera, the Altiplano-Puna volcanic complex is also a component of the Central Volcanic Zone and is formed by large calderas and lava domes such as La Torta.
The Andes are a site of volcanic activity, which is usually subdivided into four separate volcanic zones: the Northern Volcanic Zone, the Central Volcanic Zone, the Southern Volcanic Zone and the Austral Volcanic Zone. These volcanic zones are separated by gaps where no recent volcanic activity has occurred. These gaps are not static; the gap separating the Austral and the Southern Volcanic Zones has been moving northward for the past 15-20 million years. The Southern Volcanic Zone itself is subdivided into additional volcanic zones, the Northern, Transitional, Central and Southern Southern Volcanic Zone and contains over two calderas and over 60 volcanoes with Quaternary activity.
The Central Chilean Andes have an arid climate since the Miocene. Thus, a number of volcanic centres going back as far as 25 million years are well preserved. Geologically, this area belongs to the Central Volcanic Zone, a volcanic belt in the Andes, whose magmas are heavily influenced by the thick crust of the area.
Wheelwright is part of the Central Volcanic Zone, which together with the Northern Volcanic Zone, the Southern Volcanic Zone and the Austral Volcanic Zone is one among four separate volcanic zones in the Andes; these volcanic zones are separated by gaps without recent volcanic activity. Since 23 million years ago the Central Volcanic Zone has given rise to compound volcanoes, calderas and stratovolcanoes, which are formed mainly by andesitic or dacitic rocks. Ojos del Salado, a member of the Central Volcanic Zone, is the second tallest mountain in the Andes and the highest active volcano in the world. Further, the Maricunga volcanic belt in the same region is site of major precious metal deposits.