Geochemical Difference of Brannerite in Alkali Metasomatic and Acid Metasomatic Uranium Ores of Xiangshan Deposit
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摘要: 相山铀矿田是我国最大的火山岩型铀矿田，发育碱交代型、酸交代型两种类型铀矿化。前人主要侧重于酸交代型铀矿化的研究，将两种矿化类型进行对比研究较少，致使对相山矿田铀成矿作用整体认识不全面。两种类型铀矿化的成矿流体、成矿环境的对比研究对揭示相山矿田铀成矿作用全貌具有重要意义。本文以碱交代型、酸交代型铀矿石中的钛铀矿为研究对象，采用显微镜、电子探针、微区原位LA-ICP-MS分析等手段，对比研究了两种类型铀矿石中钛铀矿的地球化学成分特征，研究了两种类型成矿流体成分差异，探讨了两种类型铀矿成因。结果表明：（1）两种类型矿石中钛铀矿都具有较稳定的U、Ti 含量和Ti/U 比值，且其主要元素U、Ti、K、Na、Mg、Fe、Al、Ca、P等的含量相近；两种类型矿石中钛铀矿都富含U、Th、Pb、Nb、Y、REE等元素，具有综合利用意义；（2）两种类型矿石中钛铀矿的成矿流体性质不同，碱性成矿流体中相对富含Si、Pb、Zr、Ta、Nd等元素和CO2、Cl 等挥发份，REE、U等元素可能主要以碳酸盐、氯化物型络合物形式迁移；酸性成矿流体中更加富集F、Th、Y、重稀土元素和Cl、F、CO2等挥发份，REE、U、Th、Y等元素可能主要以碳酸盐、氯化物和氟化物型络合物形式迁移；（3）碱性、酸性成矿流体（铀）都为还原性的中高温流体，其中碱交代型钛铀矿形成环境相对稳定，酸交代型钛铀矿形成的物理化学条件变化剧烈。
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关键词:
- 碱交代型、酸交代型铀矿化 /
- 钛铀矿 /
- 地球化学特征 /
- 成矿环境 /
- 相山矿田
Abstract: As the largest volcanic rock type uranium ore field in China, Xiangshan uranium ore field is where two types of uranium mineralization are developed, alkali metasomatic type and acid metasomatic type. The predecessors mainly focused on the study of acid metasomatic uranium mineralization, but neglected the comparative study of the two types, resulting in the incomplete understanding of the overall uranium mineralization in Xiangshan ore field. The study of ore-forming fluid and ore-forming environment of the two types of uranium mineralization is of great significance to reveal the uranium mineralization in Xiangshan ore field on the whole. Taking the brannerite in the alkali metasomatic and acid metasomatic uranium ores as the research object, the geochemical composition characteristics of brannerite in the two types of uranium ores are compared and studied by means of microscopy, electron microprobe and micro area in-situ LA-ICP-MS analysis. The composition difference of uranium ore-forming fluids and the genesis of uranium deposits are also discussed. The results show that: (1) brannerite of two types have relatively stable U, Ti content and Ti / U ratio, and the contents of main elements U, Ti, K, Na, Mg, Fe, Al, Ca, P are similar. They are all rich in U, Th, Pb, Nb, Y, REE and other elements, which are of comprehensive utilization significance. (2) The ore-forming fluids of the two types of deposits are different. The alkaline ore-forming fluid is relatively rich in Si, Pb, Zr, Ta, Nd and etc., and volatile components such as CO2 and Cl, REE, U and other elements may mainly migrate in the form of carbonate and chloride complexes. The acidic ore-forming fluid is richer in F, Th, Y, and heavy rare earth elements as well as Cl, F, CO2 and other volatile components. The migration forms of REE, U, Th, Y and other elements may be mainly carbonate, chloride and fluoride type complexes. (3) Alkaline and acid ore-forming fluids (uranium) are both reducing medium high temperature fluids, while the forming environment of alkali metasomatic brannerite is relatively stable, compared with the dramatically changed physical and chemical conditions of acid metasomatic brannerite. -
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[1] 胡宝群,王倩,邱林飞,孙占学,王运,吕古贤,胡荣泉.2016.相山矿田邹家山铀矿床碱交代矿化蚀变岩石地球化学[J].大地构造与成矿学,40(2):377-385.
[2] 胡志华,林锦荣,姚亦军,王勇剑,王峰,饶泽煌,陈建平,陶意.2018a. 相山铀矿田成矿构造系统及找矿方向探讨[J].东华理工大学学报(自然科学版),41(2):124-133.
[3] 胡志华,林锦荣,王勇剑,王峰,庞雅庆,高飞.2018b.相山铀矿田红卫-沙洲岩体40Ar-39Ar 年龄及其地质意义[J].铀矿地质,34(2):90-98.
[4] 胡志华,林锦荣,王勇剑,王峰,陶意.2018c.相山矿田邹家山铀矿床钛铀矿地球化学特征及其成矿意义探讨[J].世界核地质科学,35(2):63-70.
[5] 李子颖,黄志章,李秀珍,张金带,林子瑜,张玉燕.2014.相山火成岩与铀成矿作用[M].北京:地质出版社.
[6] 林锦荣,胡志华,王勇剑,王峰.2017.相山铀矿田矿石有用共生组分研究[J].铀矿地质,33(6):340-345.
[7] 林锦荣,胡志华,陶意,王勇剑,王峰.2019a.相山矿田邹家山铀矿床成矿热事件的锆石裂变径迹年龄响应[J].铀矿地质,35(4):193-198.
[8] 林锦荣,胡志华,王勇剑,张松,陶意.2019b.相山铀矿田铀多金属成矿时代与成矿热历史[J]. 岩石学报,35(9):2801-2816.
[9] 林锦荣,胡志华,凌洪飞,兰青,杨水源,陈卫锋,刘政国.2022.华南热液铀矿时空分布规律与深源成矿机理研究[R].北京:核工业北京地质研究院.
[10] 闵茂中,张富生.1992.成因铀矿物学概论[M].北京:原子能出版社,54-59.
[11] 邱爱金.2001.江西相山铀矿田东西向隐伏构造的发现及其地质意义[J].地质论评,47(6):637-641.
[12] 双燕,毕献武,胡瑞忠,彭建堂,李兆丽,李晓敏,袁顺达,齐有强.2006.芙蓉锡矿方解石稀土元素地球化学特征及其对成矿流体来源的指示[J].矿物岩石,26(2):57-65.
[13] 王德荫,傅永全.1981.铀矿物学[M].北京:原子能出版社.王峰,林锦荣,胡志华,王勇剑.2017.居隆庵铀矿床酸碱交代叠合成矿特征[J].铀矿地质,33(3):144-149.
[14] 谢国发,姚亦军,胡志华,吉高萍.2014.相山火山盆地西部铀矿床分布特征[J].铀矿地质,30(6):328-334.
[15] 张德会,赵仑山,张本仁,陈岳龙,毛世德,杨忠芳,侯青叶,袁国礼.2013.地球化学[M].北京:地质出版社.
[16] 张金带,戴民主,邵飞,朱立庠.2005.华东铀矿地质志[R].中国核工业地质局.
[17] 赵振华.1997.微量元素地球化学原理[M].北京:科学出版社.
[18] Bau M, Moller P. 1992. Rare earth element fractionation in metamorphogenic hydrothermal calcite, magnestite and siderite [J]. Mineralogy and Petrology, 45(3): 231-246.
[19] Liu Y S, Hu Z C, Gao S, Günther, D, Xu J, Gao C G, Chen H H. 2008. In situ analysis of major and trace elements of anhydrous minerals by LA-ICP-MS without applying an internal standard [J]. Chemical Geology, 257(1-2): 34-43.
[20] Sun S, McDonough W. 1989. Chemical and Isotopic Systematic of Oceanic Basalts: Implications for Mantel Composition and Processes [J]. Special Publication of Geological Society of London, 42: 313-345.
[21] Yaxley G M, Green D H, Kamenetsky V. 1998. Carbonatite metasomatism in the Southeastern Australian Lithosphere [J]. Journal of Petrology, 39(11-12): 1917-1930.
[22] Zong K Q, Klemd R,Yuan Y, He Z Y,Guo J L, Shi X L, Liu Y S, Hu Z C, Zhang Z M. 2017. Theassembly of Rodinia: The correlation of early Neoproterozoic (ca. 900 Ma) high-grade metamorphism and continental arc formation in the southern Beishan Orogen, southern Central Asian Orogenic Belt (CAOB) [J]. Precambrian Research, 290: 32-48.
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