Subduction off the western coast of South America has been ongoing since the Jurassic and beginning with the Oligocene led to volcanism in the Puna de Atacama region, which became particularly intense 10 million years ago. Some of this volcanism was focused along faults that run perpendicular/diagonal to the subduction zone such as the Calama-Olacapato-El Toro fault; the volcanoes Cerro Tuzgle and Tastil volcanic complex are among them.