The San Pedro de Atacama oasis is located in the Antofagasta region of Chile, at 2,500 meters (8,200 feet) above sea level. The green of the area’s vegetation provides a respite from the aridity of the desert.
The oasis is irrigated by the San Pedro and Vilama rivers, formed by the union of various tributaries located in the mountains.
To the east, San Pedro is bordered by a chain of volcanos forming part of the Andes mountain range. The volcanos are of varying height and continuity, with peaks ranging from 4,500 meters (14,763 feet) to 6,000 meters (19,684 feet) above sea level. The most notable among them are the Licancabur, Lascar and Sairecabur volcanos.
The mountain ranges known as Cordillera Domeyko and Cordillera de la Sal tower to the west, with average heights of 3,300 meters (10,826 feet) and 2,550 meters (8,366 feet) above sea level respectively. Valle de la Luna is located in the Cordillera de la Sal. This valley, with its astonishingly irregular terrain, was formed by layers of sediment and vertical rocks of salt, gypsum and clay.
This region has an endorheic water system: water evaporates before reaching the sea, simultaneously dissolving the salts in the earth. When the evaporation exceeds the flow of water, great salt concentrations form. This is what occurs in the Salar de Atacama, just a few miles from San Pedro. Measuring 35 kilometers (22 miles) wide and 90 kilometers (56 miles) long, this is the biggest salt flat in the area.
Even higher up in the Andes, from 4,000 meters (13,123 feet) to 4,400 meters (14,435 feet) above sea level, is the area known as the altiplano or Puna. This large plateau of gentle, open plains was formed by material eroded from mountains and volcanos and is home to lakes, wetlands, salt flats and geysers.
EL TATIO GEYSERS: LATIN AMERICA'S LARGEST GEOTHERMAL AREA
Some 95 kilometers (59 miles) from San Pedro, El Tatio is located in the altiplano area at 4,200 meters (13,779 feet) above sea level. Around 80 active geysers, spread over an area of activity of 10 kilometers² (3.8 miles²) make this one of the world's most important geothermal areas, after Yellowstone in the United States and Dolina Giezerov in Russia.
The eruptions of water can exceed 10 meters (33 feet) and have an average temperature of 86ºC (187ºF). Measurements taken at greater depths have recorded temperatures of up to 240ºC (464ºF).
The greatest concentration of geothermal activity occurs during the morning, from 5.30 a.m. to 7.30 a.m.