20°56′32″S 68°30′12″W / 20.94222°S 68.50333°W[1]Olca-Paruma is a volcanic complex in Chile. Lying on the border between Chile and Bolivia, it is formed by an east–west alignment of volcanoes. From west to east, these are Cerro Paruma, Volcan Paruma, Olca, and Mencheca or Michincha. Aside from the mines of Ujina, Rosario, and Quebrada Blanca, the area is sparsely populated.
These volcanoes have erupted mainly lava flows, which descend their slopes. The volcanoes range in shape from long and narrow to short and stubby. Craters are found on the volcanoes. Eruptive activity commenced during the Pleistocene and continued during the Holocene. There is evidence of glaciation on the volcanoes, including moraines.
The only historical activity of unspecified character occurred during 1865–1867; the volcano may still be a threat to Bolivia and Chile. It also features vigorous fumarolic activity and has been inspected for its geothermal energy potential.