The Andes Had a Teenaged Growth Spurt

According to conventional wisdom, the towering Andes were formed slowly and gradually over 40 million years, as two tectonic plates gradually collided and buckled the earth's surface. Now a new study is revising that theory, and proposing that the mountain chain burst upwards in a growth spurt between 10 and 6 million years ago, a mere blink of an eye in geological terms. The new research doesn't dispute that the mountain range was formed in the collision of two tectonic plates — the dense Nazca Plate that underlies the Pacific Ocean and the lighter South American plate. But it adds a twist, saying that at one point during the long crash the mountains were suddenly freed of a heavy load and shot upwards towards the heavens. Researchers from the California Institute of Technology focused on a mountain region on the border between Bolivia and Peru, which has an average elevation ...