【摘要】 黑云母化学成分差异可反映出岩浆岩的性质(全岩铝饱和指数、I/S型花岗岩)、氧逸度、挥发分特征并指示岩浆源区。为了探究不同岩浆体系的性质对成矿差异性的影响,本文选择与长江中下游成矿带的武山铜矿和江南造山带的竹溪岭钨(钼)矿相关的花岗闪长斑岩中的黑云母作为研究对象,对其开展了岩相学、主量元素和原位微量元素分析。结果表明,两地黑云母均富镁贫铁,竹溪岭岩体中的黑云母相对富集Li、Nb等不相容元素,而武山岩体的黑云母富集Ni、V等相容元素。基于黑云母地球化学特征建立了成岩体系与成矿体系的联系:武山铜矿与黑云母相平衡的岩浆体系具有高Cl、高氧逸度特征,有利于Cu富集成矿;而竹溪岭钨(钼)矿的岩浆体系具高F、低氧逸度特征,有利于W富集成矿。更多还原

【Abstract】 In order to investigate the impact of different magmatic systems on metallogenic type,the authors studied the petrological and geochemical characteristics of biotite of the granodiorite porphyry from the Wushan Cu deposit in the Middle-Lower Yangtze metallogenic belt and the Zhuxiling W-Mo deposit in Jiangnan orogenic belt. The results show that the biotite of Wushan and Zhuxiling granitoids is magnesium-rich and iron-poor one. Zhuxiling biotite shows relative enrichment of incompatible elements such as Li and Nb,whereas that of Wushan displays high abundances of compatible elements such as Ni and V. Biotite geochemistry shows that these indexes are capable of reflecting A-type,I-type or S-type,oxygen fugacity,and volatile composition of host magma and thus can be used to distinguish different magma sources. Based on biotite geochemistry,the authors established the connection of different petrogenetic and metallogenic systems: the magmatic system in equilibrium with biotite of Wushan Cu deposit shows high Cl,and high oxygen fugacity,which is favorable for Cu mineralization,while the magmatic system of Zhuxiling exhibits higher F and lower oxygen fugacity,which is favorable for W mineralization.更多还原