Such landslides are common at volcanoes, where they are favoured by the steep edifices that form from lava flows being stacked on top of each other. It is not usually known what triggers the collapse, although eruption-associated earthquakes are suspected to play a role. Other volcanoes in the region with sector collapses are: Lastarria, Ollague, San Pedro, Socompa, and Tata Sabaya. The Mellado and Cerro Rosado volcanoes close to Llullaillaco also display evidence of sector collapses.