Actualité volcanique, Articles de fond sur étude de volcan, tectonique, récits et photos de voyage
The province of Neuquén in Argentina plans to create its own volcanic observatory, following the eruptions of the Puyehue and Copahue, that caused huge
material losses due to ash fallout in rural and displaced populations. They also caused disruptions in
the air traffic and penalized the results of the winter tourist season in Bariloche, already affected by the fallout of ash from the Chaiten in 2008 , and those of Llaima in 2009.
This country depends indeed of foreign organizations, mainly
SERNAGEOMIN, network monitoring the Chilean volcanoes .
Cleaning of the streets of San Carlos de Bariloche, after the eruption of the Cordon Caulle - 06.2011 - Reuters photo
Nilhue river carries hot and steaming waters in charge of ash from the eruption of the Puyehue -Cordon Caulle in 2011 - near Lago Ranco - Reuters photo
The program will focus
on monitoring in four forms : seismographs , GPS system , measures of air quality and webcams, in addition to visual observation. It will involve the national and provincial governments, and the University.
For memory, the eruptions of the Puyehue and Copahue :
According to the GVP , the last eruptive event of Copahue date of 2012-13 : it was of phreato magmatic-type and characterized by the explosions that ejected
incandescent juvenile material and dark ash that covered an area of more than 50 km. .
A 2004 study ( Varenkamp et al. )
concluded that the fluid evolution of crater lake in the 20th century suggests a gradual awakening of the volcano.
The last eruption , considered ongoing, began on 22 December 2012.
Eruption Copahue the 22.12.2012 - Photo Ant.
Huglich / AFP / NBC News
The Puyehue - Cordón Caulle has experienced significant eruptions in 1921-22 and 1960 , the latter described as VEI 3 , produced 60 million cubic meters of tephra .
The last
eruption took place on 4 June 2011 at the end of April 2012; primary explosion is responsible for issuing a plume of ash, 5 km wide, rising to 10,000 meters.
The ash cloud has passed Chilio - Argentine border to reach Villa La Angostura and Bariloche, reaching Uruguay on June 9, New Zealand on 11 June, and back to Buenos Aires in October, disrupting
the air traffic.
According to
physicists Argentines , the eruption ejected 100 million tons of ash, sand and pumice .
The plume from the
eruption of the Cordon Caulle 05.06.2011 - Photo Air Force of Chile / via Reuters
Lightning in the plume of the Puyehue -Cordon Caulle 06.06.2011 - Photo Francisco Negroni / AP / Der Spiegel
The Lanin volcano is also in the crosshairs. Despite a distant last activity listed in the year 560, it should be placed under
surveillance.
The Lanin is a basaltic to trachydacitic stratovolcano, 3737 meters high .
It was formed in four stages between the beginning of the Pleistocene and Holocene. A small lava dome summit gave lava blocks flows there 2,200 years ago . Its last eruption is dated by the GVP of the year 560. A tuff ring , post-glacial , punctuates his side SO , Argentina.
The Lanin
volcano overflown by a glider - Mountain Wave Project (research aircraft Stemme S10VT ) Photo.
All above volcanoes are located at the
Chile-Argentina border - map of Chile volcano center / south.
Sources :
- Noticias Terra - Neuquén avanza con un observatorio vulcanológico propio - link
- Global Volcanism Program - Copahue
- Global Volcanism Program - Puyehue-Cordón Caulle
- Global Volcanism Program - Lanín
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