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The 2011 Puyehue-Cordón Caulle eruption ((:puˈʝewe)) is a volcanic eruption that began in the Puyehue-Cordón Caulle volcanic complex in Chile on 4 June 2011. Misleadingly called by media the ''Puyehue eruption'' – the eruption is actually from the Cordón Caulle fissure after 51 years of the volcano being inactive.〔(Erupción del Cordón Caulle es similar a la de mayo de 1960 )〕 At least 3,500 people were evacuated from nearby areas,〔(''Volcán Puyehue: Gobierno evacua a 3.500 personas'' ) La Nación, 4 June 2011 〕 while the ash cloud was blown across cities all around the Southern hemisphere, including Bariloche, Buenos Aires, Montevideo, Stanley, Porto Alegre, Cape Town, Hobart, Perth, Adelaide, Sydney, Melbourne, Wellington and Auckland, forcing airlines to cancel hundreds of international and domestic flights and causing travel chaos. By 18 June the ash cloud had completed its first circle of the globe. The Chilean civil aviation authority said that "the tip of the cloud that has travelled around the world has more or less reached the town of Coyhaique", about 600 kilometres south of the Puyehue-Cordón Caulle. An estimated one hundred million tons of ash, sand and pumice were ejected – requiring power equivalent to 70 atomic bombs.〔Article (Chile´s Puyehue Volcano eruption equals 70 atomic bombs? ) in Buenos Aires Herald on 14 July 2011, retrieved on 14 July 2011〕 Cordón Caulle is a volcanic fissure and has erupted many times in recorded history, most recently in 1960, following the 1960 Valdivia earthquake days earlier, whereas the Puyehue stratocone has remained dormant. ==Eruption== The Southern Andean Volcano Observatory (OVDAS) of Servicio Nacional de Geología y Minería de Chile (SERNAGEOMIN) reported on 27 April 2011, 15:30 local time, an increased seismicity at the Puyehue-Cordón Caulle and set the alert Level to 3, Yellow.〔(Reporte Especial No 13 de Actividad Volcánica ) 〕 Between 20:00 on 2 June and 19:59 on 3 June, OVDAS reported〔(Reporte Especial de Actividad Volcánica No 26 ) 〕 that about 1,450 earthquakes at Puyehue-Cordón Caulle were detected, or an average of about 60 earthquakes per hour. Scientists and regional authorities flew over the volcano, noting no significant changes. The alert level remained at 3, yellow. Area residents reported feeling earthquakes during the evening of 3 June through the morning of 4 June. On 4 June, at 11:30 local time, a new round of eruption in the Puyehue volcano began. For a six-hour period on 4 June seismic activity increased to an average of 230 earthquakes per hour, at depths of 1–4 km. About 12 events were magnitudes greater than 4 of Richter magnitude, and 50 events were magnitudes greater than 3. The alert level was raised to 5, red.〔(Reporte Especial de Actividad Volcánica No 27 ) 〕 At 15:15 local time OVDAS reported an explosion and a -wide ash-and-gas plume that rose to an altitude of above sea level. The plume drifted south at altitude, and southeast and east at altitude. The alert level was raised to 6, red.〔(Reporte Especial de Actividad Volcánica No 28 ) 〕 18 days after it first erupted, lava begun spilling from the volcano, heading west and flowing "slowly by a channel about 50 meters wide and 100 feet long."〔(Puyehue volcano began to fire lava ) on 23. June 2011〕〔(Reporte Especial de Actividad Volcánica No 48 )〕 According to Argentine physicists, the eruption sent one hundred million tons of ash, sand and pumice stone, equivalent to the load of 24 million trucks of sand and released power equivalent to 70 atomic bombs. The eruption, though violent, is expected to fertilize the land and rivers.〔 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「2011 Puyehue-Cordón Caulle eruption」の詳細全文を読む スポンサード リンク
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