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DOI	10.1016/j.oregeorev.2020.103585
	Porphyry to epithermal transition at the Rongna Cu-(Au) deposit, Tibet: Insights from H-O isotopes and fluid inclusion analysis
	Zhang, Xia-Nan; Li, Guang-Ming; Qin, Ke-Zhang; Lehmann, Bernd; Li, Jin-Xiang; Zhao, Jun-Xing
通讯作者	Zhang, XN (通讯作者)
发表日期	2020
ISSN	0169-1368
EISSN	1872-7360
卷号	123
英文摘要	The giant Rongna Cu-(Au) deposit is a recently discovered low-grade composite porphyry-high sulfidation epithermal system in the Duolong ore district of central Tibet. We present fluid inclusion petrography, micro-thermometry, stable isotope (H, O), and fluid-compositional data (LA-ICP-MS) to constrain the fluid evolution of the Rongna deposit. Hydrothermal quartz and muscovite formed in the porphyry stage yielded fluid values of 8.2 +/- 1.0 parts per thousand delta O-18(H2O), and -75 +/- 19 parts per thousand delta D-H2O (n = 13). Pyrophyllite, kaolinite, and dickite define the isotopic composition of the epithermal fluid (delta O-18(H2O) = 2.2-8.3 parts per thousand, delta D-H2O = - 87 similar to 45 parts per thousand). This epithermal fluid of lighter oxygen isotope and heavier hydrogen isotope composition still has a magmatic-hydrothermal signature and rules out any significant involvement of meteoric water. The very high concentration of Cu in fluid inclusions from epithermal veins and the common sulfide replacement features suggest that the epithermal mineralization may be partially related with the dissolution and re-precipitation of the porphyry-stage sulfides. Combined with fluid inclusion petrography and microthermo-metric data, it is indicated that a single-phase fluid exsolved from magma at depth and underwent boiling and cooling, forming the porphyry alteration and mineralization. With decrease of temperature and pressure, the ascending vapor contracted into acid aqueous fluid, leaching downward to develop the telescoped high-sulfidation epithermal alteration and mineralization.
关键词	CU-AU DEPOSIT FEMTOSECOND LASER-ABLATION LA-ICP-MS MAGMATIC-HYDROTHERMAL FLUIDS NUJIANG METALLOGENIC BELT COPPER-MOLYBDENUM DEPOSIT U-PB AGES HYDROGEN ISOTOPE FUJIAN PROVINCE TECTONIC EVOLUTION
英文关键词	Porphyry-high sulfidation epithermal deposit; Fluid evolution; H-O isotopes; Fluid inclusion composition; Rongna; Tibet
语种	英语
WOS研究方向	Geology ; Mineralogy ; Mining & Mineral Processing
WOS类目	Geology ; Mineralogy ; Mining & Mineral Processing
WOS记录号	WOS:000540196600010
来源期刊	ORE GEOLOGY REVIEWS
来源机构	中国科学院青藏高原研究所
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/259974
推荐引用方式 GB/T 7714	Zhang, Xia-Nan,Li, Guang-Ming,Qin, Ke-Zhang,et al. Porphyry to epithermal transition at the Rongna Cu-(Au) deposit, Tibet: Insights from H-O isotopes and fluid inclusion analysis[J]. 中国科学院青藏高原研究所,2020,123.
APA	Zhang, Xia-Nan,Li, Guang-Ming,Qin, Ke-Zhang,Lehmann, Bernd,Li, Jin-Xiang,&Zhao, Jun-Xing.(2020).Porphyry to epithermal transition at the Rongna Cu-(Au) deposit, Tibet: Insights from H-O isotopes and fluid inclusion analysis.ORE GEOLOGY REVIEWS,123.
MLA	Zhang, Xia-Nan,et al."Porphyry to epithermal transition at the Rongna Cu-(Au) deposit, Tibet: Insights from H-O isotopes and fluid inclusion analysis".ORE GEOLOGY REVIEWS 123(2020).