| Planchón-Peteroa | |
| Elevation M: | 4107 |
| Location: | Argentina-Chile |
| Range: | Andes |
| Map: | Argentina |
| Relief: | 1 |
| Map Size: | 230 |
| Label Position: | right |
| Coordinates: | -35.24°N -70.57°W |
| Type: | Complex volcano |
| Last Eruption: | February to June 2011[1] |
Planchón-Peteroa is a complex volcano extending in a north–south direction along the border between Argentina and Chile. It consists of volcanoes of various ages with several overlapping calderas. Those include Volcán Planchón, Volcán Peteroa and Volcán Azufre.
A partial collapse of the complex about 11,500 years ago produced a major debris avalanche, which followed the course of the Teno River until reaching the Chile Central Valley.
Peteroa has a crater lake. Lagunas de Teno lies at the foot of Planchón volcano. In this area also is the Vergara International Pass.
Planchón-Peteroa Volcano erupted on September 6, followed by a stronger eruption on September 18. On September 21, the volcano erupted once again, emitting a dark gray plume of volcanic ash. As winds blew the ash southeast into Argentina, residents there were warned by authorities to evacuate the nearby areas before Planchón-Peteroa would erupt again.