Guacha caldera is part of the Altiplano-Puna volcanic complex (APVC), an igneous province in the central Andes covering a surface area of . Here on an average altitude of between 10 and 1 mya roughly of ignimbrites were erupted. Gravitic research indicates the presence of a low density area centered beneath Guacha. The magmatic body underpinning the APVC is centered beneath Guacha. Guacha caldera is also closely linked to the neighbouring La Pacana caldera.