金龙铝土矿微量元素地球化学特征与成矿环境

Geochemical Characteristics and Ore-forming Environment of the Trace Elements in Jinlong Bauxite Deposit

广西龙州县金龙铝土矿为堆积型一水铝土矿,微量元素分析表明,铝土矿石相对原始地幔富集酸土微量元素(Nb、Ta、Zr、Hf)、放射性元素(Th、U)、硫元素(Pb)等元素,而亏损碱性及碱土元素(Sr、Be)、亲硫元素(Ga)等元素。通过对Be、Th、U、Sr、Ba、V、Zr等对沉积环境指示性较强的微量元素进行含量测试分析和相关比值计算等地球化学特征研究,探讨该区铝土矿的成矿环境。研究显示金龙铝土矿成因以沉积为主,沉积环境绝大多数为海陆过渡相,成矿环境以还原环境沉积为主导,有异地沉积等成矿物质多源特征。

Jinlong bauxite deposit in Longzhou of Guangxi province is a newly discovered accumulation type bauxite deposit.Trace element analysis shows that compared with original mantle,the bauxite deposit is enriched in Nb,Ta,Zr,Hf,Th,U and Pb,but lack of Sr,Be and Ga.By analyzing geochemical characteristics of the trace elements,such as the elements content and the ratio calculation of Be,Th,U,Sr,Ba,V,Zr,which indicate good effects on sedimentary environment,the ore-forming environment of the Jinlong bauxite was discussed.Research showed that the genesis of Jinlong bauxite was major in sediments with transitional facies,and reducing ore-forming environment was significant with multi-source feature such as allochthonous deposition.