Calabozos is a ring-shaped caldera by wide, with an elevation of . Volcanoes have been formed by eruptions in the crater. The largest, which is on the southern rim of the caldera, is the Holocene Cerro del Medio complex with an elevation of . It is made mainly of andesite and dacite, and has a volume of to . On the southwestern edge several eruptions have created the Descabezado Chico volcano (elevation: ) which consists of four overlapping volcanic craters. The last eruption occurred during Holocene time, and produced a dacitic lava flow ( in volume) that extends for . Cerro Colorado, with an elevation of , forms another cone in the complex.