气候变化领域集成服务门户(CCPortal): Biotite Geochemistry and Its Implication for the Difference in Mineralization in the Xiongcun Porphyry Cu-Au Ore District, Tibet

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DOI	10.3390/min13070876
	Biotite Geochemistry and Its Implication for the Difference in Mineralization in the Xiongcun Porphyry Cu-Au Ore District, Tibet
	Tang, Pan; Tang, Juxing; Lang, Xinghai; Lin, Bin; Xie, Fuwei; Sun, Miao; Li, Faqiao; Qi, Jing; Cui, Hao; Wang, Mengdie; Xiong, Yan; Tao, Gang
发表日期	2023
EISSN	2075-163X
卷号	13 期号:7
英文摘要	The Xiongcun Cu-Au ore district is in the southern middle Gangdese Metallogenic Belt, Tibet, and formed during Neo-Tethyan oceanic subduction. The Xiongcun ore district mainly comprises two deposits, the No. I and No. II deposits, which were formed by two individual mineralization events according to deposit geology and Re-Os isotopic dating of molybdenite. The No. I deposit is similar to a reduced porphyry copper-gold deposit, given the widespread occurrence of primary and/or hydrothermal pyrrhotite and common CH4-rich and rare N-2-rich fluid inclusions. The No. II deposit, similar to classic oxidized porphyry copper-gold deposits, contains highly oxidized minerals, including magnetite, anhydrite, and hematite. The halogen chemistry of the ore-forming fluid from the No. I and No. II deposits is still unclear. Biotite geochemistry with halogen contents was used to investigate the differences in ore-forming fluid between the No. I and No. II deposits. Hydrothermal biotite from the No. I deposit, usually intergrown with sphalerite, is Mg-rich and classified as phlogopite and Mg-biotite, and hydrothermal biotite from the No. II deposit is classified as Mg-biotite. Hydrothermal biotite from the No. I deposit has significantly higher SiO2, MnO, MgO, F, Li, Sc, Zn, Rb, Tl, and Pb contents and lower Al2O3, FeOtot, Cl, Ba, Cr, V, Co, Ni, Y, Sr, Zr, Th, and Cu contents than the biotite from the No. II deposit. Hydrothermal biotites from the No. I and No. II deposits yield temperatures ranging from 230 & DEG;C to 593 & DEG;C and 212 & DEG;C to 306 & DEG;C, respectively. The calculated oxygen fugacity and fugacity ratios indicate that the hydrothermal fluid of the No. I deposit has a higher F content, oxygen fugacity, and log(fHF/fHCl) value and a lower log(fH(2)O/fHF) value than the hydrothermal fluid from the No. II deposit. The biotite geochemistry shows that the No. I and No. II deposits formed from different hydrothermal fluids. The hydrothermal fluid of the No. I deposit was mixed with meteoric waters containing organic matter, resulting in a decrease in oxygen fugacity and more efficient precipitation of gold. The No. I and No. II deposits were formed by a Cl-rich hydrothermal system conducive to transporting Cu and Au. The decreasing Cl, oxygen fugacity, and temperature may be the key factors in Cu and Au precipitation. Biotite geochemistry allows a more detailed evaluation of the halogen chemistry of hydrothermal fluids and their evolution within porphyry Cu systems.
关键词	porphyry Cu-Au deposit biotite chemistry magmatic hydrothermal Xiongcun Tibet
英文关键词	SOUTHERN LHASA SUBTERRANE; F-CL-OH; COPPER-DEPOSIT; U-PB; HYDROTHERMAL SOLUTIONS; CHEMICAL-COMPOSITION; CENTRAL PROVINCE; VOLCANIC-ROCKS; GOLD DEPOSITS; MO
WOS研究方向	Geochemistry & Geophysics ; Mineralogy ; Mining & Mineral Processing
WOS记录号	WOS:001036611100001
来源期刊	MINERALS
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/282925
作者单位	Southwest University of Science & Technology - China; China Geological Survey; Chinese Academy of Geological Sciences; Chengdu University of Technology; China University of Geosciences - Beijing
推荐引用方式 GB/T 7714	Tang, Pan,Tang, Juxing,Lang, Xinghai,et al. Biotite Geochemistry and Its Implication for the Difference in Mineralization in the Xiongcun Porphyry Cu-Au Ore District, Tibet[J],2023,13(7).
APA	Tang, Pan.,Tang, Juxing.,Lang, Xinghai.,Lin, Bin.,Xie, Fuwei.,...&Tao, Gang.(2023).Biotite Geochemistry and Its Implication for the Difference in Mineralization in the Xiongcun Porphyry Cu-Au Ore District, Tibet.MINERALS,13(7).
MLA	Tang, Pan,et al."Biotite Geochemistry and Its Implication for the Difference in Mineralization in the Xiongcun Porphyry Cu-Au Ore District, Tibet".MINERALS 13.7(2023).