Origin of The Andes

The origin of the Andes Mountains Range goes back to 50 million years ago, to the Tertiary period of the Cenozoic Era. This long chain of massive geological elevation originated by the collision of the Nazca tectonic plate against the South American plate about 50 million years ago. The portion of the Andes with highest peaks in the American continent makes the border between Argentina and Chile. Aconcagua is 6,959 m high.

This geological phenomenon of collision of plates, which gave rise to all mountain ranges in the world, is called subduction movement, which occurs at a convergent boundary between two tectonic plates of the lithosphere. To sum up, the origin of the Andes mountains is the result of a collision of plates, with the Nazca plate sliding underneath the South American one, lifting geological materials up to great heights and folding them up amid intense volcanic activities.

This slow geological process that formed the Andes range is still going on, causing strong earthquakes and sunamis in the Chilean and Peruvian coastal regions. During the orogenesis of the Tertiary, igneous rocks, such as granite, basalt, and quartz which are part of the western edge of the South American crystalline basement rock, were raised above 6,000 m of altitude. The Tertiary is a geological period of Cenozoic Era.

Below, a picture of the Andes Mountains in Patagonia, Argentina, near the Chilean border.

Below, a map showing the world’s tectonic plates, with the convergent movement of the Nazca against the South American Plate marked with a red line.