贵州天桥铅锌矿床分散元素赋存状态及规律

利用电子探针(EPMA)、电感耦合等离子质谱(ICP-MS)等分析了天桥铅锌矿床矿石矿物中分散元素的含量、赋存状态及规律,结果表明分散元素在该矿床中含量达到了综合利用评价指标,有的甚至达到了工业品位(如Cd等);这些分散元素可能以类质同象的形式赋存在硫化物矿物中,其规律为Ga、Cd、In等赋存在闪锌矿中,Ge、Tl等赋存在方铅矿中,黄铁矿中分散元素富集低;在不同颜色闪锌矿中,Ga、Cd富集规律表现为浅色闪锌矿>中色闪锌矿>黑色闪锌矿,而Ge、Tl、In、Se富集表现出中色闪锌矿相对高于浅色及黑色闪锌矿;同标本中,不同颜色闪锌矿的Ge、In富集规律在还显示浅色闪锌矿>中色闪锌矿>黑色闪锌矿,而Ga、Tl、Cd、Se富集规律呈现中色闪锌矿相对高于浅色及黑色闪锌矿.Ga/In、Zn/Cd等参数指示出矿床成因类型可能为热液-沉积-改造.

The Occurrence States and Regularities of Dispersed Elements in Tianqiao Pb-Zn Ore Deposit, Guizhou Province,China

In this study, contents, occurrence states and regularities of the dispersed elements in ore minerals of Tian-qiao Pb-Zn ore deposit were analyzed by using the methods of Electron Probe Microanalysis ( EPMA) and Inductively Coupled Plasma Mass Spectrum (ICP-MS). The results showed that the contents of dispersed elements in Tianqiao Pb-Zn ore deposit had arrived at-the level of comprehensive utilization, and some elements had even reached produc-tion grade (such as Cd, etc). The occurrence states of the dispersed elements may-be allomerism in the sulfide min-erals. Ca, Cd, In, etc, are distributed in sphalerite, and Ge, Tl, etc, are distributed in galena, and all of the ele-ments dispersed elements in pyrite are low. The concentrations of Ca, Cd in sphalerite are according the order of lightcoloured sphalerite > mesocratic sphalerite > black sphalerite, and the concentrations of Ge, Tl, In, Se in mesocratic sphalerite are higher than those in lightcoloured and black sphalerite. In the the same sample, the concen-trations of Ge, In are according the order of lightcoloured part > mesocratic part > black part, and the concentra-tions of Ga, Tl, Cd, Se in mesocratic part are higher than lightcoloured and black parts. The ratios of the Ga/In,Zn/Cd, etc indicate the metallogenetic deposit might be hydrothermal-sedimentogenic- diplogenetic- regenerated.