甘肃小铁山铅锌多金属矿床流体包裹体特征  

Characteristics of Fluid Inclusions of the Xiaotieshan Lead Zinc Polymetallic Deposit in Gansu Province

作　　者：梁婉娟[1] 严光生[1,2] 李景朝[1] 左群超[1] 杜泽忠[1,2] 甄世军[2,3] 张志辉[1,2] 李永胜[1,2] 

机构地区：[1]中国地质调查局发展研究中心,北京100037 [2]国土资源部矿产勘查技术指导中心,北京100120 [3]中国地质大学(北京)地球科学与资源学院,北京100083

出　　处：《矿物岩石地球化学通报》2016年第2期317-327,共11页Bulletin of Mineralogy, Petrology and Geochemistry

基　　金：中国地质调查局项目(12120114001301)

摘　　要：为探讨甘肃小铁山矿床的成矿流体来源、性质及其演化过程,对其含矿石英脉、重晶石样品开展了系统的流体包裹体研究。结果表明,包裹体类型主要为气液两相包裹体、纯气体包裹体、纯液体包裹体以及含CO_2的三相包裹体。显微测温结果表明,小铁山矿床下盘脉状矿体中石英的流体包裹体的均一温度为174~452℃,盐度为0.88%~9.86%NaCl_(eqv);重晶石中流体包裹体的均一温度为149~388℃,盐度为2.07%~12.16%;块状矿体中的流体包裹体均一温度为178~296℃,盐度为1.91%~14.46%NaCl_(eqv)。氢氧同位素研究显示,含矿石英脉状中δ^(18)O_(H_2O)为-1.14‰~4.68‰,δD_(V-SMOW)为-88.0‰^-153.2‰,结合包裹体的岩相学、流体性质等特征,推断成矿热液应为岩浆流体与加热海水的混合流体。In order to discuss the source, character, and the evolution process of the ore-forming fluid of the Xiaoteishan deposit A systematic fluid inclusion study has been carried out on ore-bearing quartz veins and barite samples of the Xiao- tieshan deposit. Results show that there are several types of fluid inclusions including liquid-gaseous inclusion,pure gase- ous inclusion, pure liquid inclusion, and CO：bearing three phase inclusions. The microthermometric results show that hom- ogenization temperatures and salinities of fluid inclusions in quartz and barite veins from the vein-type orebody at the bot- tom of the Xiaotieshan deposit vary from 174℃ to 452℃ and from 0.88% to 9.86% NaClcq,, and from 149℃ to 388℃ and from 2.07% to 12. 16% respectively. In addition, homogenization temperatures and salinities of fluid inclusions of the massive orebody of the Xiaotieshan deposit vary from 178℃ to 296℃ and from 1.91% to14.46% NaCleqv respectively. Hy- drogen and oxygen isotope studies show that 8180 and δDV-SMOW values of water in fluid inclusions of the ore-forming quartz vein vary from -1.14‰ to 4.68‰ and from -88.0‰ to -153.2‰, respectively. Combining the petrographical features of fluid inclusions and their fluid features, it is inferred that the ore-forming fluid of the Xiaotieshan deposit was the mixture of the magmatic fluid and the heated seawater.

关 键 词：流体 包裹体特征 Zn-Pb-Cu矿床 小铁山矿床 白银厂 

分 类 号：P618.2[天文地球—矿床学]