The arrangement of the Rocky Mountains, roughly in a north south direction, in close proximity to the western coast of the continent, is due to the geological activity in this region. They are a result of the subduction of the Pacific tectonic plate beneath the North American tectonic plate, and as a result of it, the geologic activity in the region has been immense for millions of years, which contributed to the lifting up of the surrounding area, thus creating this mountain chain.
