The large white area in the centre of the image is Salar de Uyuni. At over 10 360 square kilometres in area, Salar de Uyuni, located in southwest Bolivia, is the largest salt flat in the world. 40,000 years ago, the area was part of a large prehistorical lake - when it dried, two modern lakes (Poopo and Uru Uru) were left, along with 2 salt deserts. The smaller is called Salar de Coipasa and the larger is Uyuni. Salar de Uyuni is estimated to contain 10 billion tons of salt, which is mostly made of halite and gypsum. It lies at an altitude of over 3600 m.
In the upper half of the image, the Andes are formed by two distinct mountain ranges that appear as darker reddish-brown bands running northwest to southeast. Between the two ranges, shown in a lighter brown, sits the Altiplano plateau, which spans southern Peru and northern Bolivia. The plateau sits at 3660 meters and is covered in maze-like canyons, marshlands and lakes. The largest of the lakes — Lake Titticaca — can be seen as the dark blue patch in southern Peru. The two mountain ranges supporting the plateau eventually come together along the border of Argentina and Chile to form one continuous range.
The Andes have been forming over the past 170 million years as the Nazca Plate lying under the Pacific Ocean has forced its way under the South American Plate and pushed up its western edge. The subduction of one plate under the other has given rise to a number of volcanoes that dot the western edge of the mountain range. Earthquakes are also very common in this region.
The Altiplano is sometimes considered a separate plate or microplate. The Altiplano-Puna plateau is the second greatest plateau in the world (the Tibet Plateau being the greatest). It resulted from up to 300 km of late Cenozoic, crustal shortening at the western edge of the South American plate. This shortening generated unusually thick, hot and felsic, continental crust. In contrast to the central Andes, no high plateau exists in the northern and southern Andes. In addition to upfolding, the extreme height of the Altiplano — up to 6 km, but Its height averages about 3,300 meters — is linked to the arid climate of the region which strongly reduces erosion.