ZHANG Xiaoxu
1 School of Earth Science and Resources, China University of Geosciences, Beijing 100083, China 2 MNR Key Laboratory of Metallogeny and Mineral Assessment, Institute of Mineral Resources, Chinese Academy of Geological Sciences, Beijing 100037, ChinaLIN Bin
2 MNR Key Laboratory of Metallogeny and Mineral Assessment, Institute of Mineral Resources, Chinese Academy of Geological Sciences, Beijing 100037, ChinaTANG Juxing
2 MNR Key Laboratory of Metallogeny and Mineral Assessment, Institute of Mineral Resources, Chinese Academy of Geological Sciences, Beijing 100037, ChinaHE Liang
3 No.6 Geological Party, Tibet Bureau of Geology and Mineral Exploration and Development, Lhasa 851400, ChinaLIU Zhibo
2 MNR Key Laboratory of Metallogeny and Mineral Assessment, Institute of Mineral Resources, Chinese Academy of Geological Sciences, Beijing 100037, ChinaWANG Qin
4 College of Earth Sciences, Chengdu University of Technology, Chengdu 610059, ChinaSHAO Rui
3 No.6 Geological Party, Tibet Bureau of Geology and Mineral Exploration and Development, Lhasa 851400, ChinaDU Qiu
3 No.6 Geological Party, Tibet Bureau of Geology and Mineral Exploration and Development, Lhasa 851400, ChinaSILANG Wangdui
5 Tibet Shengyuan Mining Group Co., Ltd., Lhasa 851400, ChinaCIREN Ouzhu
5 Tibet Shengyuan Mining Group Co., Ltd., Lhasa 851400, ChinaGUSANG Quzhen
5 Tibet Shengyuan Mining Group Co., Ltd., Lhasa 851400, ChinaCIDAN Zhongga
5 Tibet Shengyuan Mining Group Co., Ltd., Lhasa 851400, ChinaThis study was jointly supported by the Research Project of Shengyuan Mining Group Co. Ltd, Tibet (Grant No. XZSYKYJT-JSFW-2019-001), the Basic Research Fund of Institute of mineral Resource, Chinese Academy of Geological Sciences (Grant Nos. KJ2102, KK2116, KK2017), the National Natural Science Foundation of China (Grant No. 41902097), the Science and Technology Plan Project of the Tibetan Autonomous Region (Grant No. XZ201901-GB-24) and Geological Survey project (Grant No. DD20190167). We thank two anonymous reviewers and the editors for their constructive comments and input.
The Mamupu skarn-type Cu-Au polymetallic deposit represents the first discovery of a medium deposit in the southern Yulong porphyry copper belt (YPCB), eastern Tibet. The Cu-Au mineralization mainly occurs as chalcopyrite in breccia, within the plate-like carbonate interlayer, being closely related to chloritization (e.g., chlorite, magnetite and epidote) and skarnization (e.g., diopside, tremolite and garnet). The ore-related quartz syenite porphyry (QSP) and granodiorite porphyry (GP) were emplaced at 40.1 ± 0.2 Ma and 39.9 ± 0.3 Ma, respectively. The QSP of Mamupu is an alkaline-rich intrusion, relatively enriched in LREE, LILE, depleted in HFSE, with no significant negative Eu and Ce anomalies, slightly high (87Sr/86Sr)i, low εNd(t), uniform (206Pb/204Pb)i and εHf(t) values, which indicates that the porphyry magma may be caused by both the mixing of metasomatized EM II enriched mantle and thickened juvenile lower crust. The QSP in the Mamupu deposit shares a similar genesis of petrology to other ore-related porphyries within the YPCB. High oxygen fugacity and water content of the magmas are essential for the formation of porphyry and skarn Cu deposits. The QSP has similar high magmatic oxidation states and water content to the Yulong deposit, which indicates that the Mamupu has a high prospecting potential. Differences in the geological characteristics and scale of mineralization between the Mamupu and other YPCB deposits may be due to the different emplacement depths of ore-related intrusions, as well as differences in the surrounding rocks.
ZHANG Xiaoxu, LIN Bin, TANG Juxing, HE Liang, LIU Zhibo, WANG Qin, SHAO Rui, DU Qiu, SILANG Wangdui, CIREN Ouzhu, GUSANG Quzhen, CIDAN Zhongga.2022. Geochronology and Geochemistry of the Mamupu Cu-Au Polymetallic Deposit, Eastern Tibet: Implications for Eocene Cu Metallogenesis in the Yulong Porphyry Copper Belt[J]. Acta Geologica Sinica(),96(4):1221-1236
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