山东省埃子王家—原疃矿区成矿流体特征及流体来源

摘 要] 通过对埃子王家-原疃矿区流体包裹体岩相学、测温学及铅、硫同位素等的分析,研究其成矿流体性质和演化,并探讨矿床成矿流体和成矿物质来源,结果表明:①流体包裹体主要为气液两相包裹体;包裹体液相成分阳离子以K⁺、Na⁺、Ca²⁺、Mg²⁺为主,阴离子以SO²₄、Cl^-、F^-为主;气相成分以H₂O、CO₂、CH₄为主;②成矿流体均一温度、盐度分别为120～350℃,4. 26%～8. 66%,为中低温(200℃以下为70%)、低盐度的流体;③²⁰⁶Pb/²⁰⁴Pb 范围为16. 217～18. 034;²⁰⁷Pb/²⁰⁴Pb 范围为15.180～16.889;²⁰⁸Pb/²⁰⁴Pb 范围为36. 586～39. 987。分析认为,本区铅同位素来源应为壳幔混合源。

Characteristics of the Ore-forming Fluid from the Aiziwangjia-Yuantuan Gold Deposit in Shandong Province and Its Origin

This paper presents analysis of the lithofacies,thermometry and sulfur isotopes of fluid inclusions from the Aiziwangjia-Yuantuan gold deposit in Shandong Province.The purpose is to study the property,evolution and origin of the ore-forming fluid of this gold deposit.The result shows that these fluid inclusions are mainly gas and fluid two-phase ones.Compositions of liquid inclusions are Na+,K+,Ca2+,Mg2+,SO2-4,Cl-and F-,and those of gas liquid are mainly H2O,CO2 and CH4.The homogenization temperature of ore-forming fluid ranges from 120℃ to 350℃,and salinity of fluid inclusions is between 4.26% and 8.66%,belonging to the middle-low temperature(≤200℃ accounting for 70%)and low salinity fluid.In Pb isotope values,206Pb/204Pb ranges from 16.217 to 18.034;207Pb/204Pb ranges from 15.180 to 16.889,208Pb/204Pb ranges from 36.586 to 39.987,respectively,and δ34S(‰) ranges from-4.7 to +4.7.The analysis suggests that these isotopes have a mixed material source from crust and mantle.