The volcano is formed from alternating layers of ignimbrite and lava, and consists of coalesced stratovolcanoes and seven separate coulees. Ice cover makes discerning its structure difficult, but about six separate peaks as well as six not readily recognisable summit craters have been counted. Additional lava domes form a southeastward trending line on the southwestern side of the volcano and dikes crop out close to Lake Pallarcocha. Coropuna overlies the margin of a buried caldera.