Study on fluid inclusions of the Boka gold deposit in central Yunnan

被引:0
作者
Xiao X. [1 ,2 ]
Yu X. [1 ,2 ]
Zhang X. [1 ]
Xiao E. [1 ]
Qi Q. [1 ]
Wang W. [1 ]
You B. [1 ]
Liu R. [1 ]
机构
[1] East China Mineral Exploration and Development Bureau for Non-ferrous, Nanjing
[2] Fujian Jindong Mining Co., LTD, Sanming
来源
| 1600年 / Science Frontiers editorial department卷 / 24期
关键词
Boka gold deposit; Central Yunnan; Fluid inclusion; Hydrothermal mineralization; Magmatic hydrothermal deposit;
D O I
10.13745/j.esf.yx.2016-11-26
中图分类号
学科分类号
摘要
The Boka gold deposit is located in the Dongchuan ore concentration area of the central Yunnan Proterozoic copper-polymetallic belt. The Au-bearing veins, stockwork and breccias occured in the strata of the Middle Proterozoic Kunyang Group and are controlled by faults. Hydrothermal mineralization of the deposit can be divided into stages 1, 2 & 3, respectively named the quartz-pyrite, the quartz-polymetallic sulfide and the quartz-calcite stage. Our studies of deposit characteristics show that stage 1 and 2 were the main Au mineralization stages. Based on the study of fluid inclusion, which included petrography, homogenization temperature and liquid/gas composition analyses, the characteristics and evolution of the ore-forming fluid were further investigated. The results show that the homogenization temperatures of the ore-forming fluid are in the ranges of 105-368℃, 119-294℃ and 115-195℃ and salinities in the ranges of 7.59-44.32 wt.% (NaCleq), 5.26-17.87 wt.% (NaCleq) and 4.18-14.57 wt.% (NaCleq) for stages 1, 2 and 3, respectively. Content studies of fluid inclusions indicate the gas composition of the ore-forming fluid are mainly H2O with little CO2, whereas the liquid composition are mainly Na+ and Cl- with small amount of Ca2+ and SO42-. Clearly the main types of the ore-forming fluid belong to the NaCl-H2O system. We conclude that the Boka deposit is a typical magmatic hydrothermal deposit based on its geological and fluid inclusion features. © 2017, Editorial Office of Earth Science Frontiers. All right reserved.
引用
收藏
页码:309 / 318
页数:9
相关论文
共 14 条
[1]  
Cline J.S., Bodnar R.J., Can economic porphyry copper mineralization be generated by a typical calc-alkaline melt?, Geophysical Research Letters, 96, B5, pp. 8113-8126, (1991)
[2]  
Bodnar R.J., Fluid inclusion evidence for a magmatic source for metal in porphyry copper deposits, Mineralogical Association of Canada Short Course, pp. 139-152, (1995)
[3]  
Philips G.N., Zhou T., Gold-only deposits and Archean granite, Society of Economic Geologists Newsletter, 37, (1999)
[4]  
Bodnar R.J., Reviced equation and table for determining the freezing point depression of H<sub>2</sub>O-NaCl solutions, Geochimica et Cosmochimica Acta, 57, pp. 683-684, (1989)
[5]  
Bodnar R.J., Vityk M.O., O-NaCl Fluid Inclusions in Minerals: Methods and Applications, pp. 117-130, (1994)
[6]  
Kerrich R., Gold R.J., Groves D.I., Et al., The characteristics, origins and geodynamic setting of supergiant gold metallogenic provinces, Science in China: Series D, 43, pp. 1-68, (2000)
[7]  
Heinrich C.A., Fluid-fluid interactions in magmatic-hydrothermal ore formation, Review in Mineralogy and Geochemistry, 65, pp. 363-387, (2007)
[8]  
Chen Y.J., Pirajno F., Wu G., Et al., Epithermal deposits in North Xinjiang, NW China, International Journal of Earth Sciences, 101, 4, pp. 889-917, (2012)
[9]  
Rodder E., Composition of fluid inclusions, US Geological Survey Professional Paper, 440, (1992)
[10]  
Philips G.N., Evans K.A., Role of CO<sub>2</sub> in the formation of gold deposits, Nature, 429, pp. 860-863, (2004)