吉林荒沟山铅锌矿床热液叠加成矿作用流体来源及特征研究

荒沟山铅锌矿床为吉南老岭多金属成矿带内的代表性矿床之一,矿体产于元古宙老岭群珍珠门组之中,受地层和韧性剪切带控制。在成矿后期,矿床经历了热液叠加成矿作用,其对成矿元素的进一步富集起到重要作用。为探究热液叠加成矿作用中流体的来源及特征,采用流体包裹体显微测温及C、H、O同位素地球化学的研究方法对热液叠加成矿期各阶段流体的性质进行研究,结果表明:Ⅰ阶段即黄铁矿-石英阶段成矿流体属中低温、低盐度的NaCl-H2O体系;流体包裹体的δDH2O为-74.8‰~-87.4‰,δ18OH2O为8.3‰~9.8‰,δ13CV-PDB为-9.6‰~-10.8‰,具岩浆水的特点。Ⅱ阶段即方铅矿-石英阶段成矿流体为低温、低盐度的NaCl-H2O体系;流体包裹体的δDH2O为-91.4‰~-93.9‰,δ18OH2O为3.3‰~4.7‰,δ13CV-PDB为-9.5‰~-10.5‰,具岩浆水与大气降水混合流体的特点,但仍以岩浆水作用为主。

Hydrothermal Superimposed Mineralization,Characteristics and Source of Ore-Forming Fluids of the Huanggoushan Pb-Zn Deposit,Jilin Province

Occurred in Zhenzhumen Formation of Proterozoic Laoling Group, the Huanggoushan Pb-Zn deposit is controlled by stratum and ductile shear belt, serving as one of the most representative deposits in Laoling polymetallic metallogenic belt, southernJilinProvince.Hydrothermal superimposed mineralization was occured in the late ore-forming stage and exerted an important influence on further enrichment of ore-forming elements.In order to explore the sources and characteristics of the fluid, the microthermometry and C-D-O isotopic geochemistry methods of fluid inclusions are used to research the nature of the ore-forming fluids in each stage of hydrothermal superimposed mineralization. Results indicate thatthe ore-forming fluidof the first stage belongs to mid-low temperature, low-salt NaCl-H2O system. The δDH2O, δ18OH2O and δ13CV-PDB of these fluid inclusions are -74.8‰~-87.4‰, 8.3‰~9.8‰ and -9.6‰~-10.8‰, respectively, showingsome characteristics of magma water. The ore-forming fluid of the second stage belongs to low-temperature, low-salt NaCl-H2O system. The δDH2O, δ18OH2O and δ13CV-PDB of these fluid inclusions are -91.4‰~-93.9‰, 3.3‰~4.7‰ and -9.5‰~-10.5, respectively, which show some characteristics about mixture fluid of meteoric water and magma water, however the magma water still play a main role.