How wide is Cerro Blanco?
Cerro Blanco (volcano)
Nevado Tres Cruces lies to the west and Nevado Ojos del Salado lies to the southwest of the Cerro Blanco centre. East-northeast running fault systems are controlled by local tectonics and may be responsible for the formation of the Cordillera de San Buenaventura. The 4-3.7 mya Laguna Amarga west of Cerro Blanco erupted rhyolites, unlike Cerro Blanco's ignimbrites.[5] The better known Cerro Galán caldera lies 80 kilometres (50mi) northeast of Cerro Blanco.[1] It forms a southwest-northeast volcanic line with Cerro Blanco and Incapillo. This line was active less than 2.5 mya ago.[3] Another trend is defined by the Culampaja line running from Sierra Nevada over Cerro Cóndor and Cerro Peinado to Blanco.[6] Other volcanic centres in the region are the Miocene-Pliocene ignimbrites Las Juntas and Las Papas. Minor bimodal–mafic volcanic centres during the Pleistocene–Holocene include volcanoes in the Pasto Ventura, Salar de Carachi Pampa and Volcán Negro Peinado areals. Felsic centres include Chascón and Cueros de Purulla.[4] Cerro Purulla lies north-northwest of Cerro Blanco and the La Hoyada volcanic complex lies directly west.[7] 4,380 metres (14,370ft) Cueros de Purulla and 4,290 metres (14,070ft) Chascón are major sources of obsidian in the Puna of Catamarca region.[8]