JiamaGranite porphyryPorphyry Cu depositOxygen fugacityGangdeseCONTINENTAL COLLISION ZONESLHASA TERRANE IMPLICATIONSMAGMATIC OXIDATION-STATEJURASSIC VOLCANIC-ROCKSORE-BEARING PORPHYRIESISOTOPIC COMPOSITIONSCOPPER-DEPOSITSULTRAPOTASSIC MAGMATISMGEOCHEMICAL CONSTRAINTSEARLY SUBDUCTION