Gabbroic complexes
Gabbroic complexes
Late Jurassic, ~148 Ma
Unnamed small gabbro intrusions in central and southern Sierra Nevada. Unit also occurs in various small bodies, mainly in east-central Sierra Nevada, intruding and adjacent to Snow Lake roof pendant (the northern part of unit SL). Many other very small bodies, too small to display at 400,000 scale, occur in central and southern Sierra Nevada. Mainly a composite suite of gabbro, fine-grained diorite, and hornblende gabbro with large crystals. Extremely variable in grain size, texture, and composition. Unit has same compositional range, similar structural relations, and coeval U-Pb zircon ages (~148 Ma; Lahren and others, 1990) with main part of the Independence Dike Swarm.