BackgroundLlullaillaco volcano was formed in 2 main stages.
The old volcano (Llullaillaco I) was built as a broad cone of thick dacitic lava flows. The upper part of this volcano collapsed about 150,000 years ago, producing a major debris-avalanche which extends eastward into Argentina. The avalanche diverged around the north and south sides of the older Cerro Rosado stratovolcano 17 km east of Llullaillaco and the two lobes stopped at 25 and 23 km distance, respectively. The deposit covers 165 km2 and is still very well preserved, thanks to the extremely arid climate, where weathering and erosion are almost absent.
The second stage (Llullaillaco II, the present-day volcano) began ca. 10,000 years ago and built the present-day cone on top of the older volcano. It, too, consists mainly of dacite domes and lava flows.
Historic activity consisted of small explosive eruptions and a possible small lava flow in the 19th century.
In 1983–85 American archaeologist Dr Johan Reinhard discovered Inca remains on the summit and the slopes of Llullaillaco. In 1999, 3 500-year-old frozen mummies were found at an altitude of 6,739 m. The mummies were buried with more than 100 objects, including textiles, gold and silver statues, pottery. The mummy of a girl feathered a rich ceremonial headdress.
The mummies are extraordinarily well preserved because of the extremely cold, hypoxic, and arid environment of their mountain tomb. The frozen bodies of Llullaillaco are among the best-preserved mummies ever found.
See also: Sentinel hub | Landsat 8