中文摘要:河北省东坪碲化物金矿床是我国迄今为止发现的一个比较典型的碲化物金矿床，矿化为含金石英大脉和含金钾长石脉，两者之间在空间上为过渡关系。为探讨成矿流体的来源，尤其是地幔流体参与成矿的程度，笔者从研究成矿流体人手，应用显微测温、激光拉曼光谱分析对矿区主矿脉进行了比较系统的流体包裹体均一温度、盐度、成分的测试，并测定了He- Ar同位素组成。结果显示，东坪碲化物金矿床中的流体包裹体主要为C02 - NaCl-H20型和HzD NaCI型，整体以CO2广泛发育为特征；矿区的成矿温度为250~400℃，集中于300～340℃；成矿压力为40~180 MPa，主要为60～100 MPa;流体成分主要为C02和H20，含少量H2S、N2、CH4、CO和C2H2；流体盐度硼(NaCIeq)为5%～7%；流体总密度为0.48~0.79 g/cm3;矿脉中石英的R/Ra比值高达0.3~5.2，明显高于地壳流体（0.001)。基于碲富集、高．R/Ra比值、成矿流体富COz，笔者认为矿床成矿作用与地幔洁动有着密切的关系。
Abstract:The Dongping deposit is a unique typical gold telluride deposit ever discovered in China. Gold mineralization occurs either as auriferous quartz veins or as fractured auriferous K-feldspar veins, which connect each other in strike. In this paper the homogenization temperatures and salinity of the fluid inclusions as well as their composition and He-Ar isotopic components were systematically measured based on samples from No.l and No.70 Veins, the most important gold veins in the mine. The fluid inclusions in the Dongping mine can be divided into CO2 and H2O types, both characterized by enrichment in CO2. The fluid inclusion bubbls are 10—30 pm in diameter, mostly in the range of 10～ 20 ym. The first melting temperatures of CO2 range from - 56.2 to - 57.4℃ , and their melting temperature of CO2-clathrates vary from +5.1 to +7.61℃ . The homogenization temperatures of H2O-rich CO2 inclusions homogenizing into the aqueous liquid phase are 247 to 365℃ , whereas the homogenizations of CO2-rich three-phase CO2 inclusion homogenizing into gas phase (CO2 phase) are 255～372℃. The salinities of this type of inclusions are 5 wt%～7 wt% NaCI. The homogenization temperatures of H2O type fluid inclusions are 160～ 430℃, in which 290～ 350℃ characterize the primary fluid inclusions and 160～230℃ characterize the secondary ones. Their salinities are 5.4 wt%～8.0 wt%NaCl. The measurement by Laser Raman Spectroscopy shows that both gas phase and liquid phase are enriched in CO2 and H2O, with minor amounts of H2S, N2, CH4, CO and C2H2. CO2 inclusions are extensively developed in some gold deposits of the world. As for their genesis, there are three possibilities inferred, presumably related to magmatism, metamorphism, and mantle degasses respectively. He-Ar isotopic analyses of fluid inclusions in the Dongping mine indicate that R/Ra ratios reach 0.3— 5.2, in which 2.1～5.2 mark No.l ore vein whereas 0.3～0.8 mark No. 70 0re vein. These data are much higher than 0.001 of the fluids in the crust. Moreover, tellurium is an element of affinity for the mantle and the core. The considerable accumulation of tellurium in the crust is abnormal, probably having to do with mantle activity. Therefore, the above data demonstrate that the Dongping gold telluride is genetically related to mantle fluids.
keywords:gold telluride deposit,fluid inclusion,He-Ar isotope,metallogenesis,Dongping,Hebei Province
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基金项目:国家重大基础研究项目（编号：G1999043211）
引用文本：
毛景文， 李荫清.2001.河北省东坪碲化物金矿床流体包裹体研究：地幔流体与成矿关系[J].矿床地质,20(1):23~36.2001.Fluid Inclusions of the Dongping gold Telluride Deposit in Hebei Province,China: Involvement of Mantle Fluid in Metallogenesis[J].Mineral Deposits20(1):23~36
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