中文摘要:内蒙古碾子沟钼矿床位于中亚-蒙古巨型造山带东段,是一中型石英脉型钼矿床,矿体赋存于燕山期中粗粒黑云母二长花岗岩内的断裂带中,矿体与岩体空间关系密切。文章对赋矿围岩和主要金属硫化物分别开展了单颗粒SHRIMP锆石U-Pb定年和硫同位素测试。获得的黑云母二长花岗岩加权平均年龄为(152.4±1.6) Ma(MSWD=0.28);8件辉钼矿δ34S值为3.50‰~6.23‰,平均为4.38‰;8件黄铁矿δ34S值为4.60‰~8.83‰,平均为5.62‰。结合相关研究成果进一步确定成矿(154.3±3.6 Ma)与黑云母二长花岗岩密切相关,成矿物质来源于岩浆,与黑云母二长花岗岩的形成过程密切相关。
Abstract:The Nianzigou ore deposit is a medium-size quartz vein type molybdenum deposit occurring in the Central Asian-Mongolian belt of Inner Mongolia. Its major ore bodies are associated spatially with the Yanshanian medium-coarse grained biotite monzogranite. In order to investigate the relationship between mineralization and diagenesis, the authors applied the SHRIMP dating technique to determining U-Pb ages of zircons from the biotite monzogranite. 13 analyses yielded a 206Pb/238U weighted mean age of (152.4±1.6) Ma(MSWD=0.28), which suggests that the biotite monzogranite was formed in the Late Jurassic. In addition, this age is quite close to the molybdenite Re-Os isochronic age of (154.3±3.6) Ma. Sulfur isotope analyses of molybdenite and pyrite yielded δ34S values ranging from 3.50‰ to 6.23‰, averaging 4.38‰, and from 4.60‰ to 8.83‰, averaging 5.62‰, respectively. The δ34S values of the molybdenite and pyrite have characteristics of magma sulfur. Comprehensive studies indicate that the mineralization was in close relation with the diagenesis.
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基金项目:本文得到国家自然科学基金面上项目(40972065)和国家重点基础研究项目(2006CB403507)的资助
引用文本:
张作伦,刘建明,曾庆栋.2011.内蒙古碾子沟钼矿床SHRIMP锆石U-Pb年龄、硫同位素组成及其地质意义[J].矿床地质,30(6):1122~1128张作伦,刘建明,曾庆栋.2011.SHRIMP zircon U-Pb dating and sulfur isotope compositions of Nianzigou molybdenum deposit in Inner Mongolia and their geological significance[J].Mineral Deposits30(6):1122~1128
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