Precambrian petrochemistry of the northern Park Range, Colorado, and its implications for studies of crustal derivation studies of sillimanite-grade Proterozoic rocks, particularly mafic and ultramafic intrusive bodies ; local and statewide volume-weighted chemistry ; and comparison of local crust-mantle chemical models with Earth crust-mantle chemical models - Snyder, George L.; Brandt, Elaine L.; Smith, Vertie C. (United States Government Print. Office, 1988)