Geological characteristics and genesis of the Jurassic No. I porphyry Cu–Au deposit in the Xiongcun district, Gangdese porphyry copper belt, Tibet

• DOI: 10.1016/j.oregeorev.2015.02.008
• Publication Date: 2015-02-07T16:41:09Z
• Authors: Juxing Tang; Xinghai Lang; Fuwei Xie; Yiming Gao; Zhijun Li; Yong Huang; Feng Ding; Huanhuan Yang; Li Zhang; Qin Wang; Yun Zhou
• Keywords: Diorite; Molybdenite; Hypogene; Quartz monzonite; Stockwork; Breccia; Polymetallic replacement deposit; Argillic alteration

The Xiongcun district, located in the western segment of Gangdese porphyry copper belt (GPCB), hosts only known Jurassic mineralization GPCB, Tibet, PRC. No. I deposit district is related to Middle quartz diorite (167–161 Ma) and was formed at ca. 161.5 ± 2.7 Ma. Ore-bearing emplaced into Early volcano-sedimentary rock sequences Formation. Veinlets disseminated developed within surrounding metamorphosed tuff, hosting a measured indicated resource 1.04 Mt copper, 143.31 t gold 900.43 silver with an average grade 0.48% 0.66 g/t gold, 4.19 silver. can be assigned four stages, including three main stages hypogene one epigenetic stage. alteration associated potassic. Seven mineralization-related hydrothermal veins have been recognized, quartz–sulfide, biotite–sulfide, magnetite–sulfide, quartz–molybdenite–sulfide, chalcopyrite–pyrite–pyrrhotite, pyrite polymetallic veins. S Pb isotopic compositions ore sulfides Re contents molybdenite suggest mantle source for ore-forming materials minor contamination from subducted sediments. Hydrogen oxygen isotope ores that both magmatic meteoric waters were involved process. ore-bearing (161.5 ages correspond time northward subduction Neo-Tethys oceanic slab. geochemical data indicate intra-oceanic island arc setting originated partial melting limited contribution genesis interpreted as being slab Ma).