Geologists reveal the Americas collided millions of years earlier than thought

Volcanic rocks in Colombia are rewriting the timeline of the collision between Central and South America. Their magnetic signatures show that major tectonic deformation had already weakened by the late Miocene, suggesting the most intense collision occurred earlier than previously believed. Geologists reveal the Americas collided millions of years earlier than thought.

By examining the magnetic characteristics of volcanic rocks in Colombia’s Northern Andes, researchers found evidence that the main phases of collision took place earlier than previously believed, before about 10 million years ago. The research was led by Victor Piedrahita (first author) and J. Li (corresponding author), along with an international group of geoscientists.

Their work centered on late Miocene volcanic rocks (about 12-6 million years old) from the Combia Volcanic Province in central Colombia. These rocks formed during a key period when the South American Plate was interacting with the continental portion of Central America.