A volcano is an opening, or rupture, in a planet's surface or crust, which allows hot magma, volcanic ash and gases to escape from below the surface.
Volcanoes are generally found where tectonic plates are diverging or converging. A mid-oceanic ridge, for example the Mid-Atlantic Ridge, has examples of volcanoes caused by divergent tectonic plates pulling apart; the Pacific Ring of Fire has examples of volcanoes caused by convergent tectonic plates coming together. By contrast, volcanoes are usually not created where two tectonic plates slide past one another. Volcanoes can also form where there is stretching and thinning of the Earth's crust in the interiors of plates, e.g., in the East African Rift, the Wells Gray-Clearwater volcanic field and the Rio Grande Rift in North America. This type of volcanism falls under the umbrella of "Plate hypothesis" volcanism. Volcanism away from plate boundaries has also been explained as mantle plumes. These so-called "hotspots", for example Hawaii, are postulated to arise from upwelling diapirs with magma from the core-mantle boundary, 3,000 km deep in the Earth.
Chaitén is a volcanic caldera 3 kilometres (2 mi) in diameter, 17 kilometres (11 mi) west of the elongated ice-capped Michinmahuida volcano and 10 kilometres (6 mi) northeast of the town of Chaitén, near the Gulf of Corcovado in southern Chile. The most recent eruptive phase of the volcano began on 2 May 2008, and is ongoing. According to the Global Volcanism Program, radiocarbon dating of older tephra from the volcano suggests that its last previous eruption was in 7420 BC ± 75 years.
The caldera rim reaches 1,122 metres (3,681 ft) above sea level. Before the current eruption, it was mostly filled by a rhyolite obsidian lava dome that reached a height of 962 metres (3,156 ft), partly devoid of vegetation. Two small lakes occupied the caldera floor on the west and north sides of the lava dome.
The translucent grey obsidian which had erupted from the volcano was used by pre-Columbian cultures as a raw material for artifacts and has been found as far away as 400 kilometres (250 mi) to the south and north, for example in Chan-Chan.
Chile i/ˈtʃɪliː/ or ˈtʃɪleɪ, officially the Republic of Chile (Spanish: República de Chile [reˈpuβlika ðe ˈtʃile] ( listen)), is a country in South America occupying a long, narrow strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far south. Along with Ecuador, it is one of two countries in South America that do not border Brazil. The Pacific coastline of Chile is 78,563.2 kilometres. Chilean territory includes the Pacific islands of Juan Fernández, Salas y Gómez, Desventuradas and Easter Island. Chile also claims about 1,250,000 square kilometres (480,000 sq mi) of Antarctica, although all claims are suspended under the Antarctic Treaty.
Terms of Service · Privacy

