American Cordillera

The American Cordillera is a chain of mountain ranges (cordilleras) that consists of an almost continuous sequence of mountain ranges that form the western "backbone" of North America, South America and Antarctica. It is also the backbone of the volcanic arc that forms the eastern half of the Pacific Ring of Fire.

From north to south, this sequence of overlapping and parallel ranges begins with the Alaska Range and the Brooks Range in Alaska and runs through the Yukon into British Columbia. The main belt of the Rocky Mountains along with the parallel Columbia Mountains and Coast Ranges of mountains and islands continue through British Columbia and Vancouver Island. In the United States, the Cordillera branches include the Rockies, the Sierra Nevada, the Cascades, and various small Pacific coastal ranges. In Mexico, the Cordillera continues through the Sierra Madre Occidental and Sierra Madre Oriental, as well as the backbone mountains of the Baja California peninsula.

The ranges of the Cordillera from Mexico northwards are collectively called the North American Cordillera or Western Cordillera in the United States and Canada, and also named as the Canadian Cordillera or Pacific Cordillera in Canada.

The Cordillera continues on through the mountain ranges of Central America in Guatemala, Honduras, Nicaragua, Costa Rica, and Panama, and becomes the Andes Mountains of South America. The Andes with their parallel chains and the island chains off the coast of Chile continue through Colombia, Venezuela, Ecuador, Peru, Bolivia, Argentina, and Chile to the very tip of South America at Tierra del Fuego. The Cordillera continues along the Scotia Arc before reaching the mountains of the Antarctic Peninsula.

Further reading

• Silberling, N.J. et al. (1992). Lithotectonic terrane map of the North American Cordillera [Miscellaneous Investigations Series I-2176]. Reston, Va.: U.S. Department of the Interior, U.S. Geological Survey.