Early Tertiary to Late Cretaceous granitic rocks

Porphyritic to equigranular granite to diorite emplaced during the Laramide orogeny. Larger plutons are characteristically medium-grained, biotite +/- hornblende granodiorite to granite. Smaller, shallow-level intrusions are typically porphyritic. Most of the large copper deposits in Arizona are associated with porphyritic granitic rocks of this unit, and are thus named 'porphyry copper deposits'. (50-82 Ma)
State Arizona
Name Early Tertiary to Late Cretaceous granitic rocks
Geologic age Late Cretaceous to Early Tertiary
Lithologic constituents
Major
Igneous > Plutonic > Granitic > Granodiorite (Pluton)
Igneous > Plutonic > Granitic > Granite (Pluton)
Igneous > Plutonic > Dioritic > Diorite (Pluton)
Comments Laramide metaluminous; associated with porphyry Cu deposits
References

Richard, S.M., Reynolds, S.J., Spencer, J.E., and Pearthree, P.A., 2000, Geologic Map of Arizona: Arizona Geological Survey Map 35, 1 sheet, scale 1:1,000,000.

Titley, S.R., and Anthony, E.Y., 1989, Laramide mineral deposits in Arizona, in Jenney, J.P., and Reynolds, S.J., editors, Geologic evolution of Arizona: Arizona Geological Society Digest 17, p. 485-514.

Blakey, R.C., 1989, Triassic and Jurassic geology of the southern Colorado Plateau, in Jenney, J.P., and Reynolds, S.J., editors, Geologic evolution of Arizona: Arizona Geological Society Digest 17, p. 369-396.

NGMDB product
Counties Apache - Cochise - Gila - Graham - Greenlee - La Paz - Maricopa - Mohave - Pima - Pinal - Santa Cruz - Yavapai - Yuma