Petrology and crystal chemistry of the Ruby Star granodiorite, Pima County, Arizona

摘要: The Laramide -aged Ruby Star batholith consists of an outer equigranular granodiorite rim and inner porphyritic core. A quartz monzonite stock breaches the southern together with discontinuous bodies biotite diorite host Sierrita -Esperanza porphyry copper deposit. whole rock data indicate that crystallized at 650 to 700 C a fH2O 1800 2000 bars. Analyses show Mg enrichmentin simultaneous Fe enrichment in rock. These trends presence magnetite suggest high increasing f02. dehydration reaction Czamanske Wones (1973) suggests crystallization occurred f02 10 -1' -56 bars 750 C. temperature -f02 conditions match those required for hydrothermal fluids carry sulphur species complex (Burnham Ohmoto, 1 98$) .