Were The Rocky Mountains There Forever?

The Rocky Mountains are part of the Cordilleran mountain system, which formed over millions of years. The process of mountain building or orogeny is complex and involves the collision of tectonic plates. The Rocky Mountains began forming about 80-100 million years ago, when the Farallon Plate, a large tectonic plate, subducted beneath the North American Plate. As the Farallon Plate descended into the Earth's mantle, it heated up and melted, forming magma. This magma rose to the surface and erupted through the crust, building up the Rocky Mountains. The Rocky Mountains have continued to be shaped and uplifted by tectonic activity and erosion over millions of years.