The Caldera Lauca is a

caldera A caldera ( ) is a large cauldron-like hollow that forms shortly after the emptying of a magma chamber in a volcano eruption. When large volumes of magma are erupted over a short time, structural support for the rock above the magma chamber ...

in the Arica y Parinacota Region of

Chile Chile, officially the Republic of Chile, is a country in the western part of South America. It is the southernmost country in the world, and the closest to Antarctica, occupying a long and narrow strip of land between the Andes to the eas ...

. It is located in the Cordillera Occidental, in the valley of the

Lauca River The Lauca River is a binational river. It originates in the Chilean Altiplano of the Arica and Parinacota Region, crosses the Andes and empties into Coipasa Lake in Bolivia. The upper reach of the river lies within the boundaries of Lauca Nation ...

. The elliptic caldera has an east-west extension of and in north-south direction, buried beneath the late Miocene Vilañuñumani-Tejene volcanic complex in the north and ending at Chucal in the south. The 21

mya Mya may refer to: Brands and product names * Mya (program), an intelligent personal assistant created by Motorola * Mya (TV channel), an Italian Television channel * Midwest Young Artists, a comprehensive youth music program Codes * Burmese ...

Oxaya Ignimbrite originates in the caldera. The eastern border of the caldera is buried beneath younger ignimbrites and deposits but is located east of the Guallatiri volcano. An

Oligocene The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but ...

fault marks the western edge of the caldera. The caldera is filled up to thick with of

ignimbrite Ignimbrite is a type of volcanic rock, consisting of hardened tuff. Ignimbrites form from the deposits of pyroclastic flows, which are a hot suspension of particles and gases flowing rapidly from a volcano, driven by being denser than the surro ...

. Rocks have varying SiO₂ content from 58 to 73%. One sample of Lauca ignimbrite is younger than the Lauca caldera. It forms one of the older volcanic centres in the Payachata region, together with the Ajoya- Choquelimpie volcanic complex and the Caquena domes, while Pomerape and Parinacota are more recent volcanic centres.

References

{{coord missing, Chile Calderas of Chile Miocene calderas Volcanoes of Arica y Parinacota Region

See also

References