柿竹园钨多金属矿床的Re-0s同位素等时线年龄研究  

Re-Os ISOTOPIC CHRONOLOGY OF MOLYBDENITES IN THE SHIZHUYUAN POLYMETALLIC TUNGSTEN DEPOSIT,SOUTHERN HUNAN

作　　者：李红艳[1] 毛景文[1] 孙亚利[2] 邹晓秋[2] 何红蓼[2] 杜安道[2] 

机构地区：[1]中国地质科学院矿床地质研究所 [2]中国地质科学院岩矿测试技术研究所

出　　处：《地质论评》1996年第3期261-267,共7页Geological Review

摘　　要：柿竹园钨多金属矿床产于千里山复式岩体与泥盆系碳酸盐岩的接触部位。其成矿时代以往都是用矿体附近的花岗岩体年龄来间接推断。我们最近采用辉钼矿的Re-Os等时线定年法直接测定了与千里山第一期花岗岩有关的夕卡岩型矿体的矿化年龄为151.0±3.5Ma。该年龄晚于第一期花岗岩,但早于第二期花岗岩,从而证实了钨多金属矿化在花岗岩系列的早期早阶段也可以成矿。该年龄与野外观察的地质情况十分吻合,而辉钼矿是热液矿床中的常见矿物,说明这种测年方法是一种研究热液矿床成矿时代及其成因的重要手段。The Shizhuyuan polymetallic tungsten deposit was formed in the contact between the Qian-lishan granite and Devonian limestone. The Qianlishan granite stock is composed of pseudopor-phyritic biotite granite, equigranular biotite granite and granite porphyry. There are close spacio-temporal relationships between the multiple phases of granitic rocks and multiple periods of mineralization in the Shizhuyuan polymetallic tungsten deposit. Massive skarn ores of the first period are associated with the pseudoporphyritic biotite granite. Previously, the age of mineralization was deduced by the age of granite near the deposit. Using the Re-Os isochron method of molybdenites, the authors measured directly the mineralization age of skarn W-Sn-Mo ore related to the first-period granite of the Qianlishan granite stock, and obtained a 187Re-187Os age of 151. 0±3. 5 Ma. This age is relatively younger than the first period of granite but older than the second period of granite. This fact proves that molybdenite mineralization can occur in the early period of granite series. This result is in good agreement with geological relation in the field, and suggests that the Re-Os isochron method can be used in the measurement of the mineralization age and the study of the genesis of hydrothermal deposits.

关 键 词：等时线 矿化年龄 辉钼矿 多金属矿床 铼 锇 

分 类 号：P618.510.2[天文地球—矿床学]