The sustained magmatic activity along the North American Cordillera during late Mesozoic and Paleogene times produced the emplacement of numerous porphyry copper deposits. This activity extended by most of western México, particularly along the northwestern part of the country. This region, along with Arizona and New Mexico in the United States, contains one of the most important centers of copper mineralization on Earth. Most of the Mexican deposits lie in the eastern part of the Laramide magmatic belt (90–40 Ma) and were formed predominantly between 75 and 50 Ma. The largest deposits occur in northeastern Sonora and are represented by...