Rb-Sr dating of sphalerite, sulfur and lead isotopes of sulfides was analyzed to confirm the age of mineralization and to de?termine the origin of the ore-forming material. The Rb-Sr dating of sphalerite from the Tangbian deposit yielded an isochron age of 477±5Ma(MSWD=1.2), which is in agreement with the isochron age of 486±6Ma from the Bukouchang deposit in the range of er?ror, suggesting that the mineralization of Pb-Zn occurred in the early Ordouician. δ34S values of pyrite, galena and sphalerite range from+25.2‰to+36.1‰, similar to data obtained by previous studies of other sediments-hosted Pb-Zn deposits in eastern Guizhou and western Hu'nan. It is held that the sulfur of the Tangbian Pb-Zn deposit originated from marine sulfates and/or underlying star?ta. Lead isotope analysis of galena and sphalerite yielded 208Pb/204Pb ratios varying from 38.389 to 38.584, 207Pb/204Pb ratios varying from 15.737 to 15.790, and 206Pb/204Pb ratios varying from 18.181 to 18.217, with relative highμvalues from 9.75 to 9.86. The re?sults suggest that the source of lead was mainly derived from the upper crust. Besides, some data of lead isotope point to magmatic source, which probably resulted from the extraction of lead by the ore-forming fluids from magmatic rocks.%对贵州铜仁塘边铅锌矿床开展闪锌矿Rb-Sr测年和黄铁矿、方铅矿、闪锌矿S、Pb同位素分析,以获得矿区的成矿年龄,探讨其成矿物质来源.塘边铅锌矿床闪锌矿Rb-Sr等时线年龄为477±5Ma(MSWD=1.2),与前人获得的卜口场矿区闪锌矿Rb-Sr等时线年龄486±6Ma在误差范围内一致,表明矿床形成于加里东早期.黄铁矿、方铅矿、闪锌矿S同位素变化于+25.2‰~+36.1‰之间,与湘西—黔东主要铅锌矿床相似,明显富集重硫,认为S可能来源于寒武系海水碳酸盐和/或下伏地层.方铅矿、闪锌矿Pb同位素208Pb/204Pb值为38.389~38.584,207Pb/204Pb值为15.737~15.790,206Pb/204Pb值为18.181~18.217,μ值为9.75~9.86,显示铅主要来源于上地壳.
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