Ojos del Salado The elevation of Ojos del Salado has been the subject of debate. The mountain is hidden behind other peaks and thus its height was not appreciated in early research until 1937, when the mountain was climbed by Polish climbers. A 2006 article in Andes Magazine offered that Ojos del Salado may be higher than Aconcagua, although the argument was premised on older, less accurate altitude surveys. The results of these older surveys assigned Ojos del Salado an elevation of , which would have made it nearly higher than Aconcagua. As early as 1955, an estimate was made that the elevation
Ojos del Salado of the Nazca Plate beneath the South America Plate became increasingly shallower and this caused volcanism to shift from the Maricunga Belt to the Ojos del Salado region. The Paleozoic basement crops out only northwest of Nevado Tres Cruces. Other geologic units in the region are Oligocene sedimentary units and volcanic rocks ranging from Oligocene age to less than 1.5 million years old. The area is part of a tectonic boundary between a volcanically active region north of the boundary and a less volcanically active region south of the boundary, which is also characterized by geographical differences, e.g. the presence