Geologic map of North America. On the west side of North America, adjacent to the Pacific Ocean, is the Cordilleran Mountain Chain, the main focus of our regional geological discussions. (Courtesy of USGS.)
Geologic map of North America. On the west side of North America, adjacent to the Pacific Ocean, is the Cordilleran Mountain Chain, the main focus of our regional geological discussions. (Courtesy of USGS.)