内蒙古十八倾壕金矿床的叠加成矿作用——来自黄铁矿组分特征的证据  

Multiple Mineralization of Shibaqinghao Gold Deposit in Inner Mongolia:Evidences from the Compositions of Pyrite

作　　者：梁一鸿[1] 张宏颖[2] 秦亚[1] 刘雪松[3] 

机构地区：[1]吉林大学地球科学学院,长春130061 [2]吉林大学机械科学与工程学院,长春130022 [3]吉林大学地质博物馆,长春130061

出　　处：《吉林大学学报（地球科学版）》2012年第1期77-81,共5页Journal of Jilin University：Earth Science Edition

基　　金：国家自然科学基金项目(40372095)

摘　　要：通过矿石中黄铁矿的ΔFe/ΔS值和Co/Ni值的分析,确定了内蒙古十八倾壕金矿床两种矿体———糜棱岩型矿体和石英脉型矿体中黄铁矿组分的不同特点:糜棱岩型矿体的黄铁矿属于贫铁贫硫型,Co/Ni值小于1;石英脉型矿体的黄铁矿属于贫铁富硫型,Co/Ni值大于1。这与该矿床两种矿石的S和Pb同位素的组成特征相呼应:前者反映同韧性剪切作用有关的变质热液成矿;后者反映岩浆热液成矿作用。这又一次在物质成分上证明了十八倾壕金矿床是两次成矿作用叠加的结果,同时也证明了前人提出的'不同层次叠加构造控矿'的观点。Through determination of values of ΔFe/ΔS and Co/Ni of pyrite,two types of ore bodies were distinguished in Shibaqinghao gold deposit,Inner Mongolia,which are myloniteand quartz vein ore bodies,respectively.The pyrites in mylonite ore body are poor in Fe and S with Co/Ni ratios less than 1;whereas the pyrites in quartz vein ore body are poor in Fe but rich in S with Co/Ni ratios greater than 1.These features are consistent with S and Pb isotope compositions of the two types of ore bodies;the former type may represent metamorphic thermal solution related metallogeny in association with ductile shear deformation,and the later maybe products of magmatism related metallogeny.Our results prove that Shibaqinghao gold deposit formed from a multiple stages of mineralization,and thus support a previously proposed point that ＂the deposit was controlled by structures of different stages and levels＂.

关 键 词：金矿 韧性剪切带 叠加成矿作用 

分 类 号：P618.51[天文地球—矿床学]