中文摘要：

茂租铅锌矿床位于云南省东北部,赋存于上震旦统灯影组白云岩中,矿体主要呈似层状和脉状,矿石主要由闪锌矿、方铅矿、黄铁矿和方解石等组成。应用TIMS对选自茂租铅锌矿床主成矿期的5件闪锌矿单矿物进行了Rb-Sr同位素组成分析。结果显示,全部闪锌矿样品的Rb含量较低（0.05×10-6~0.18×10-6）,Sr含量亦不高（0.33×10-6~10.02×10-6）,87Rb/86Sr值变化范围较小,为0.052~0.850,87Sr/86Sr值较高,变化范围为0.7117~0.7210。虽然本次分析结果未获得理想的Rb-Sr等时线年龄,但根据年龄（200 Ma）校正后的87Sr/86Sr值（0.7106~0.7186）,具有示踪成矿流体/物质来源的重要意义。与赋矿灯影组白云岩、区域寒武—二叠系沉积岩、峨眉山玄武岩和元古代基底岩石（昆阳群、会理群等）的87Sr/86Sr200 Ma值相比,茂租闪锌矿87Sr/86Sr值明显高于除基底岩石外的其它地质体,表明茂租铅锌矿床成矿流体可能来源或流经了基底岩石,并与来源或流经盖层岩石的流体发生了混合。结合前人资料,本文认为流体混合作用是导致茂租铅锌矿床形成的重要机制,加强流体运移途径的研究,对寻找新的矿体具有重要的理论指导意义。

英文摘要：

Maozu Pb-Zn deposit is located in the Sinian Dengying Formation dolomite, in the northeast of Yunnan Province, China. Its ore bodies show bedded, vein and irregular shapes. Ores are composed of sphalerite, galena, pyrite and calcite. Through analysis by using TIMS, the Rb-Sr isotopic compositions of five sphalerite separates samples were acquired. Results show that Rb and Sr contents of sphalerite are low, with ranges of 0.05×10-6 to 0.18×10-6 and 0.33×10-6 to 10.02×10-6, respectively. The 87Rb/86 Sr values are between 0.052 and 0.850. The 87Sr/86 Sr values range from 0.7117 to 0.7210. Although the sphalerite samples do not yield ideal Rb-Sr isochron age, the 87Sr/86 Sr values can trace the sources of ore-forming fluids/metals after age-corrected（200 Ma）. Compared with the initial 87Sr/86 Sr values of ore-hosting Dengying Formation dolostone, Cambrian to Permian sedimentary, Emeishan flood basalts and Proterozoic basement rocks（Kunyang and Huili Groups）, the 87Sr/86Sr（0.7106 to 0.7186） values of sphalerite separates from Maozu Deposit are higher than all the related geological bodies except basement rocks. Therefore, we suggest that the ore-forming fluids/metals may be derived from or flowed through the Proterozoic basement rocks, and than mixed with the fluids that derived from or flowed through the covering rocks. The mixed fluids mineralization is an important metallogenic mechanism for Maozu deposit, so the study of fluid migration way has an important theoretical guiding significance for finding new ore bodies.