Apacheta-Aguilucho is a volcanic complex formed by two volcanoes, Cerro Apacheta and Cerro Aguilucho, both composite volcanoes; with the highest summit of the complex reaching a height of . The northern Aguilucho volcano and the southern Apacheta volcano are in their central portions formed by rhyolitic lava flows, with the surrounding edifice formed by andesitic-dacitic lavas. An andesitic lahar and pyroclastic flow crops out south and east of Apacheta, which as the oldest part of the edifice is heavily eroded. North and east of the complex, the two lava domes Chac-Inca and Cerro Pabellón form the youngest part of the volcano.