Re-Os同位素体系已成为金属矿床定年和示踪的重要手段之一.文章在简述Re-Os同位素体系基本原理基础上,综述了国内外的最新研究成果,认为Re-Os同位素测试对象不再局限于辉钼矿和铜镍硫化物矿石,黄铁矿、毒砂、磁黄铁矿、镍黄铁矿、闪锌矿等也常作为测试对象用于金矿床、铅锌矿床、沉积喷流型钴(金)等矿床的定年.地壳岩石与原始地幔相比,具有较高的187Os/188Os比值、γos值以及Re/Os比值,因此,硫化物或矿石的Re-Os同位素组成和普通Os—Re/Os比值图解可以揭示斑岩矿床、金矿、铅锌矿以及铜镍硫化物矿的成矿物质来源.辉钼矿则可以通过Re含量来示踪成矿物质来源.Re-Os同位素也可与其他同位素结合(如187Os/188Os—87Sr/86 Sr)共同判明不同端元组分对成矿的贡献.%Re-Os isotope system has become one of the most important age dating and tracing methods of metal deposits. The principle of Re-Os isotope system and the basic chemical properties of rhenium and Osmium are briefly sketched and new research results at home and acroad are systemically reviewed. Now Re-Os isotope analysis is not confined to date molybdenite and Cu-Ni sulfide ore and the analysis Re-Os i-sotope analysis of pyrite, arsenopyrite, pyrrhotite, pentlandite and sphalerite are often used to date gold deposits, lead-zinc deposits and Sedex cobalt (gold) deposits. Compared with primitive mantle, the crust rocks have higher 187Os/188Os, γOs and Re/Os values, so the Re-Os isotopic compositions of sulfides or ores and the Os—Re/Os diagram can be used to trace the origins of ore-forming materials in porphyry deposits, gold deposits, lead-zinc deposits and Cu-Ni sulfide deposits while rhenium content of molybdenite could trace the ore-forming materials sources. Combined with other isotopic analysis (187 Os/188Os —87Sr/ 86 Sr) Re-Os isotope systems could discriminate the contribution of different end-member components in the ore-forming materials.
展开▼
