Thousands Evacuated As Chile Issues "Red Alert" for Copahue Volcano

Authorities in Chile have ordered the mandatory evacuation of an area about 16 miles around the active Copahue volcano, which straddles the border with Argentina.

Located several hundreds of miles southeast from the Chilean capital of Santiago, the volcano, sited in the so-called Bio Bio region, has shown growing seismic activity in recent weeks, although it still has not erupted, according to a report by Reuters.

The volcano "is now in a process that risks turning into an eruption," and for "that reason we've issued a red alert," Interior Minister Andres Chadwick said during a nationally-televised news conference.

The latest update from Chile's National Geological and Mining Service, known as Sernageomin, said over 250 small earthquakes related to magma movement are being recorded per hour at Copahue, even though continuous volcanic tremor, which would indicate almost certain eruption, has not been recorded yet, Wired reported.

It's estimated about 2,240 people will be evacuated.

In Argentina's nearby Neuquen province, authorities declared a "yellow alert," but said evacuations weren't necessary. Nevertheless, school classes in Argentina's Caviahue-Copahue community, home to about 900 people, were suspended.

Copahue sits on layers of sedimentary and volcanic rocks ranging in age from Eocene to Pliocene eras.

The modern volcano became active an estimated 1.2 million years ago and the contemporary caldera formed between 0.6 to 0.4 million years ago, during which was also produced large pyroclastic flows that extending up to 23 miles from the volcano.

The modern structure is an elongated shield volcano, with a maximum thickness upwards of 14 miles in some places.

There have been at least six eruptions within the current Holocene era, with the most recent on December 22, 2012.

Although the lake emptied during a 2000 eruption, it has returned to its previous levels.

When Chile's Puyehue-Cordon Caulle chain erupted in mid-2011, ash from a volcano forced the cancellation of hundreds of airline flights, particularly in neighboring Argentina and Uruguay.