Sierra Madre Occidental Sierra Madre Occidental The Sierra Madre Occidental is a major mountain range system of the North American Cordillera, that runs northwest–southeast through Northwestern and Western Mexico, and along the Gulf of California. The Sierra Madre is part of the American Cordillera, a chain of mountain ranges (cordillera) that consists of an almost continuous sequence of mountain ranges that form the western "backbone" of North America, Central America, South America and Antarctica. The Spanish name "sierra madre" means "mother mountains" and "occidental" means "western" in English, with these being the "Western Mother Mountains". To the east, from the Spanish "oriental" meaning
Abajo Mountains predominant igneous rock is porphyritic hornblende diorite. Ages of intrusion in the Abajo Mountains fall in the interval from 22 to 29 million years. These mountain ranges are part of the Colorado Plateau province west of the greater ranges of the Rocky Mountains. The laccolith ranges are much younger and have a very different geologic origin. The range was reputedly named by the Spanish in the 1700s, the name "Abajo" meaning "low". Abajo Mountains The Abajo Mountains, known locally as the Blue Mountains or The Blues, is a small mountain range west of Monticello, Utah, south of Canyonlands National Park