 Subduction of the Nazca Plate beneath the South America plate is responsible for most of the volcanism in the Central Volcanic Zone. After activity in the western Maricunga Belt volcanic arc ceased six million years ago, volcanism started up in the Incapillo region, forming the high volcanoes Monte Pissis, Cerro Bonete Chico and Sierra de Veladero. Later, a number of lava domes formed between these volcanoes.
