Nevado San Francisco

Nevado San Francisco, or Cerro San Francisco (Spanish pronunciation: [saɱ fɾanˈθisko]), is a stratovolcano on the border between Argentina and Chile, located just southeast of San Francisco Pass. It is considered extinct and is one of the several 6,000 m (19,700 ft) peaks in the area, of which the chief is the Ojos del Salado.

Nevado San Francisco
Highest point
Elevation	6,016 m (19,738 ft) [1]
Coordinates	26°55′S 68°15′W
Geography
Location	Argentina-Chile
Parent range	Andes
Geology
Age of rock	1.34 - 1.32 million years ago
Mountain type	Stratovolcano
Last eruption	Unknown

The volcano is part of the Central Volcanic Zone of the Andes.[2] It is composed from andesite with the exception of basaltic cones and lava flows on the eastern side. These cones are part of the Peinado lineament and a sample was dated 200,000 years ago by argon chronology.[3]^:74-75 They are noteworthy for their olivine phenocrysts.[2] One lava flow less than one million years old reaches a length of 11 kilometres (6.8 mi).[4] The western slopes contain dacitic lava domes.[5] On the summit lie two circle-shaped constructs, of Inca or Formative period ages.[3]^{:351, 432}