Tocomar is part of the Andean Volcanic Belt's Central Volcanic Zone, which runs along the western margin of South America and lies in the countries of Peru, Bolivia, Chile and Argentina. The Central Volcanic Zone features about 44 active volcanoes as well as several large ignimbrite caldera systems; some of these are part of the Altiplano-Puna volcanic complex. About 200 of all volcanoes in the Andes have been active during the Holocene, 66 of these in historical times. The date of the last eruption of Tocomar is not known with certainty but was in the Pleistocene.