Cerro Nicholson, a small isolated scoria cone, was constructed on a plain WSW of Chachani volcano and WNW of El Misti volcano. Andesitic bombs surround the crater of this relatively young volcanic feature that displays a well-preserved crater at the summit of the scoria cone and has a morphology similar to the Holocene Andahua scoria cones farther to the north. Cerro Nicholson was erupted through a 1.65-million-year-old Arequipa Airport Ignimbrite deposit erupted from a now-buried site beneath the Chachani volcanic complex.