Arizona Geological Society: Cenozoic Tectonic Extension in the Sonoran Desert Region and Reconstruction of the Initial Distribution of Porphyry Copper Deposits
In the past ~30 Ma, severe tectonic extension in the Sonoran Desert region roughly doubled the land area and halved the crustal thickness. Before this time a high mountain range in this area was the source of clastic debris shed southwestward toward the Pacific continental margin and northeastward onto what is now the Colorado Plateau....