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Pacaya is an active complex volcano in Guatemala, which first erupted approximately 23,000 years ago and has erupted at least 23 times since the Spanish invasion of Guatemala. Pacaya rises to an elevation of . After being dormant for a century, it erupted violently in 1965 and has been erupting continuously since then. Much of its activity is Strombolian, but occasional Plinian eruptions also occur, sometimes showering the area of the nearby Departments with ash.〔 Pacaya is a popular tourist attraction. Pacaya lies 30 kilometers (19 miles) southwest of Guatemala City and close to Antigua.〔Google Earth〕 The volcano sits inside the Escuintla Department.〔 So far, the last activity reported has been the eruption that peaked on March 2, 2014 causing ash to rain down in Guatemala City, Antigua and Escuintla. ==Geological history== The Pacaya volcano is a part of the Central American Volcanic Arc, a chain of volcanoes stretching from the northwest to the southeast along the Pacific coast of Central America, formed by the tectonic subduction of the Cocos Tectonic Plate beneath the Caribbean Plate. Pacaya lies on the southern edge of a sizable volcanic caldera formed in the Pleistocene age which contains Lago de Amatitlán. This caldera has been the source of at least nine very large explosions over the past 300,000 years, erupting a total of about of magma.〔 After the last caldera-forming eruption 23,000 years ago several smaller vents within and around the caldera have seen eruptive activity. Pacaya is the largest post-caldera volcano, and has been one of Central America's most active volcanoes over the last 500 years. It has erupted at least 23 times since the Spanish conquest,〔 producing basalt and basaltic andesite.〔(Guatemala Volcanoes )〕 About 1,100 years ago, the volcano's edifice collapsed, causing a huge landslide. Deposits from the landslide travelled about from the volcano down to the Pacific coastal plain. The landslide left a large crater, within which the current active cone has grown. The presence of a magma chamber at shallow depths beneath Pacaya means that distortion of the cone leading to instability and future landslides remains a hazard to the surrounding areas.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Pacaya」の詳細全文を読む スポンサード リンク
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