Lauca (volcano)

Lauca volcano is a 5,140 metres (16,860 ft) high andesitic stratovolcano in the Central Volcanic Zone of the Andes in the Altiplano in northern Chile. It was active 10.5 million years ago. Amphibole rich lava flows formed a uniform volcanic cone. A later major ignimbrite eruption caused the collapse of the centre and formed the Lauca ignimbrite. A caldera is present, with a lava dome at the northeastern rim.

Andesites from the Lauca volcano exist in two groups, plagioclase rich ones which underwent alteration and fine grained silicic ones that are fresher. The territory is underpinned with a crust formed from rocks of Precambrian to Cretaceous age, with thicknesses up to 70 kilometres (43 mi).