Genesis of the Late Triassic Southwest Zone Breccia-Hosted Alkalic Porphyry Cu-Au Deposit, Galore Creek, British Columbia, Canada

摘要

The Late Triassic Southwest zone alkalic porphyry Cu-Au deposit in the Galore Creek district, northwestern British Columbia, is hosted in hydrotherraally cemented breccias that overprinted older matrix-rich breccia and megacrystic orthoclase-phyric syenite and monzonite dikes. Synmineralization cemented breccias and biotite-phyric monzodiorite dikes are localized at the contact of the matrix-rich breccia and host syenite and monzonite dikes, as well as in crosscutting faults. Regional shortening tilted the Southwest zone deposit so that the cemented breccias now dip 50° to 60° southwest.