Cerro Chanka
Cerro Chanka is a Pleistocene lava dome in the Andes. It is part of the Altiplano-Puna [volcanic complex]. Potassium-argon dating indicates that the dome last erupted 119.8±5.4 ka ago. Another reported age is 1.5±0.1 mya.
The dome is located on the northwestern side of Cerro [del Azufre]. It is constructed from three lobes with diameters of. The flanks of the dome are steep and talus and lava blocks lie at its feet.
Cerro Chanka has a SiO2 content of 66% and is of calc-alkaline origin. The lavas are potassium-rich dacitic and rhyolitic save for an andesitic mafic component, and rich in crystals.