Puyehue Volcano, Chile - John Seach

Puyehue volcano in Chile erupted on Saturday 4th June 2011 after 51 years of inactivity. On the 3th June a seismic swarm occurred with 1450 earthquakes registered at the volcano, associated with magma movement under the volcano. The earthquakes has a focus of 2-5 km depth on the southeast flank of the volcano. More than 130 earthquakes were greater than magnitude 2. On Saturday 4th of June the volcano alert was raised to level RED after a marked increase in seismic activity. Over a period of six hours there more than 230 earthquakes per hour with a focus of 1-4 km depth. Twelve of the earthquake were greater than magnitude 4.0, 50 greater than magnitude 3.0. More than half the earthquakes were over magnitude 2.0. The largest earthquake occurred at 8:36 am local time on 4th June with a magnitude 4.4. Residents reported felt earthquakes on Friday evening and Saturday morning. The explosive eruption began on Saturday 4th June producing a 10 km high ash column. More than 600 people were evacuated from the area. Volcanic ash fell in the city of Bariloche in Argentina, and the airport was closed. Residents of Bariloche said that ash fell like a snowstorm. The Argentine government has sent military troops to help residents affected by the ashfall. A border crossing between Chile and Argentina at Cardenal Samore was closed due to the eruption creating poor visibility on the mountain pass. The last eruption of Puyehue volcano was in 1960 following a 9.5 earthquake.
More on Puyehue volcano...