| Olca | |
|---|---|
 | |
| Highest point | |
| Elevation | 5,407 m (17,740 ft) |
| Coordinates | 20°56′0″S 68°29′0″W / 20.93333°S 68.48333°W |
| Geography | |
  Olca | |
| Location | Bolivia, Nor Lípez Province, San Pedro de Quemes Municipality, Cana Canton Chile, Antofagasta Region, El Loa Province |
| Parent range | Andes |
| Geology | |
| Mountain type | Stratovolcano |
| Last eruption | 1867 |
Olca is a stratovolcano on the border of Chile and Bolivia. It lies in the middle of a 15 km long ridge composed of several stratovolcanos. Cerro Minchincha lies to the west and Paruma to the east. It is also close to the pre-Holocene Cerro Paruma. It is andesitic and dacitic in composition, with lava flows extending several kilometres north of the peak. The only activity from the ridge during historical times was a flank eruption from 1865 to 1867. The exact source of this eruption is unclear.