Jurassic granitic rocks

Granite to diorite, locally foliated and locally alkalic; includes Triassic(?) granitoids in the Trigo Mountains. This unit includes two dominant assemblages of igneous rocks. The Kitt Peak-Trigo Peaks superunit includes, from oldest to youngest: dark, foliated or gneissic diorite, medium-grained equigranular to porphyritic granodiorite, and small, irregular intrusions of light-colored, fine-grained granite. The Ko Vaya superunit, limited to south-central Arizona, includes texturally heterogeneous K-feldspar-rich granitic rocks. (150-180 Ma)
State Arizona
Name Jurassic granitic rocks
Geologic age Jurassic
Lithologic constituents
Igneous > Plutonic > Granitic > Granodiorite (Batholith)
Igneous > Plutonic > Granitic > Alkali-feldspar-granite > Alkali-granite (Batholith)
Igneous > Plutonic > Dioritic > Diorite (Batholith)
Stratigraphic units Kitt Peak-Trigo Peaks superunit, Ko Vaya superunit

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.

Tosdal R.M., Haxel, G.B., and Wright, J.E., 1989, Jurassic geology of the Sonoran Desert region, southern Arizona, southeastern California, and northernmost Sonora: Construction of a continental-margin magmatic arc, in Jenney, J.P., and Rey

NGMDB product
Counties Cochise - La Paz - Maricopa - Pima - Santa Cruz - Yuma