中文摘要：

位于扬子地块西南缘的川滇黔铅接壤区，是我国独具特色的铅锌银多金属矿集区，黔西北铅锌矿床是其重要的组成部分。黔西北铅锌成矿区内业已发现铅锌矿床（点）100余处，其赋矿围岩为泥盆至二叠系白云岩或白云质灰岩，而其分布严格受到三条区域性构造带的控制，其中大部分矿（化）体产于北西向褶皱＋断裂构造体系中。在系统收集前人发表的有关矿床硫同位素数据基础上，对成矿流体中硫的来源及形成机制进行了详细的探讨。11个矿床的150件硫化物硫同位素组成介于＋3．5‰～＋20．3‰，多数集中在＋6‰～＋20‰分布，峰值处于＋10‰～＋14‰，具有明显的塔式正态分布特征。可见硫化物明显富集重硫同位素，与在0‰附近的陨石硫不同。前人研究发现泥盆至二叠系沉积地层中，普遍发育膏盐层，其中硫酸盐硫同位素组成介于＋12‰～＋28‰，与泥盆至二叠纪海水硫酸盐硫同位素组成相似（＋18‰～＋30‰）。硫酸盐热化学还原（TSR）可以使体系中的硫同位素组成降低15‰，因此，黔西北铅锌矿床成矿流体中的还原硫主要是TSR的产物，即蒸发岩是主要的硫源。

英文摘要：

Located in the western margin of the Yangtze block, SW China, the Pb-Zn deposits in NW Guizhou Province are important parts of the Sichuan-Yunnan-Guizhou Pb-Zn metallogenic province. In this region, more than 100 Pb-Zn deposits hosted in the Devonian to the Permian dolostone or dolomific limestone have been reported, which are structurally controlled by three regional tectonics and most of which are controlled by NW-trend fold-fault systems. This paper collects 150 sulfur isotopic data of sulfides from 11 deposits, of which δ34S values range from ＋3.5‰ to ＋20.3‰; most of them are centralized between ＋6‰ and ＋20‰ and peak in ＋10‰ to ＋14‰, and show a normal distribution features. The heavy sulfur isotopes are enriched in sulfides and are different from that of the meteorite sulfur （0‰）. The δ34S values are similar to that of sulfate-beating evaporates in the host rocks （＋12‰ to ＋28‰） and the Devonian to the Permian seawater sulfate （＋18‰ to ＋30‰）. Because △34Ssulfate-sulfide could up to ＋15‰ in the hydrothermal Zn-Pb mineralizing systems, so the reduced sulfur in hydrothermal fluids was likely derived from evaporates in the host rocks by thermo-chemical sulfate reduction （TSR）.