安徽月山矿田硅、氦、氖同位素地球化学研究

Silicon, Helium and Neon Isotope Geochemistry of Cu,Au Ore Deposist in the Yueshan Orefield, Anhui Province

对安徽月山矿田硅、氦、氖同位素组成研究表明 ,月山岩体是玄武质岩浆结晶分异和同化混染的产物 ,矿床的硅来自岩浆熔 流分离作用形成的岩浆热液 ,成矿流体中的氦来自地壳和地幔两个端员。成矿过程中发生了富含放射性成因氦的演化大气降水与岩浆热液的混合。

Based on studies of Silicon, helium and neon isotope geochemistry of Cu, Au deposits in the Yueshan orefield , Anhui province. It is shown that the Yueshan dioritic body was formed by assimilation and crystallization of basaltic magmas, silicon in ore deposits came from the magmatic hydrothermal fluids formed by melt-fluid partition, helium in the ore-forming fluid in this orefield mainly came from two end-members: the crust and the mantle. The former was evolutional meteoric water with higher radioactive helium, while the latter magmatic water produced by melt-fluid partitioning of the crustal assimilated dioritic melts. Mixing between the evolved meteoric water and the the magmatic water had taken place during the mineralization processes.