Planchon-Peteroa Volcano Activity Increases and May Be Near Eruption

A volcano near the Argentine-Chilean border expelled an ash plume on Wednesday. Argentine scientists monitoring the Volcano stopped short of issuing a yellow alert for Planchón-Peteroa Volcano. They did note there has been more ash and smoke Emmit from the volcano in recent days.

Argentina's National Service of Geology and Mining monitors the volcano and installed three seismic stations, and a camera to help monitor conditions at the Planchón-Peteroa Volcano. The lead volcanic Argentine agency reported that some water from snow and ice melt may be seeping into a magma chamber and becoming super heated. The explosive expansion of the steam and gas that occurs when magma and water interact may be the cause for the increased activity.

At Planchón, steam ash plumes reaching upwards to a little more than 600 feet have been observed. Some ash fall was noted about 10 km away from the volcano when an overflight was made on September 7th. The scientists did not note any changes to the glacier complex on the volcano during the overflight. Any change to the ice formations would be an indicator of heating within the mountain.

The volcano's last eruption was in 1998. There was a major collapse of the volcano complex about 11,500 years ago that produced a large avalanche of debris that flowed through the Tenco River and into the Chile Central Valley.

The volcano complex stretches in a north-south direction along the border Argentina and Chile. The complex is made up of several volcanoes that site atop overlapping calderas. Since it is late winter in the Andes mountains any eruption by the Planchón-Peteroa volcano could lead rapid snow and ice melt. This could result in a major debris flow or avalanche due to the intense heat produced by an eruption.

The closes city to the volcano is the city of Malargüe. It has 23,000 inhabits and is located in the southwest province of Mendoza. There are no current plans to enact and special measures for the inhabitants of Malargüe based on the current activity at the volcano.

Sources:
http://earthobservatory.nasa.gov/NaturalHazards/view.php?id=45914
http://www.sernageomin.cl/index.php?option=com_content&task=view&id=565&Itemid=1
http://www.losandes.com.ar/notas/2010/9/22/peteroa-sigue-activo-pero-descartan-declarar-alerta-amarilla-516379.asp