Strontium isotopic signature of hydrothermal sedimenta- tion from Early Cambrian barite deposits in east Guizhou,China  

作　　者：XIAFei MADongsheng PANJiayong SUNZhanxue CAOShuanglin NIEWenming WUKai 

机构地区：[1]StateKeyLaboratoryforMineralDepositsResearch,DepartmentofEarthSciences,NanjingUniversity,Nanjing210093,China//EastChinaInstituteofTechnology,Fuzhou344000,China [2]StateKeyLaboratoryforMineralDepositsResearch,DepartmentofEarthSciences,NanjingUniversity,Nanjing210093,China [3]EastChinaInstituteofTechnology,Fuzhou344000,China

出　　处：《Chinese Science Bulletin》2004年第24期2632-2636,共5页

摘　　要：The ore genesis model for barite deposits in east Guizhou Province has been in dispute and the major debate focuses on whether they are product of the submarine hydrothermal sedimentation. This note presents new stron- tium isotope data from 19 samples of Dahebian and Yuping barite deposits, and their 87Sr/86Sr ratios are significantly lower than that of the coeval seawater. The Sr/86Sr ratios of 87 17 samples out of 19 samples rang from 0.708310 to0.708967, indicating that theymight be related to the mantel admixture. Two isotopic ratios in this study are higher than those of coeval seawater (0.7090), collected from late-stage barite mineral vein of interpenetrative strata and a barite nodule bearing hypidiomorphic granular pyrite, which indicates that they might be related to the continental admixture. The study provides Sr isotopic evidence not only for the subma- rine hydrothermal exhalative genesis of Dahebian and Yup- ing barite deposits, but also for distinguishing the barite mineralization of late stage.The ore genesis model for barite deposits in east Guizhou Province has been in dispute and the major debate focuses on whether they are product of the submarine hydrothermal sedimentation. This note presents new stron- tium isotope data from 19 samples of Dahebian and Yuping barite deposits, and their 87Sr/86Sr ratios are significantly lower than that of the coeval seawater. The Sr/86Sr ratios of 87 17 samples out of 19 samples rang from 0.708310 to0.708967, indicating that theymight be related to the mantel admixture. Two isotopic ratios in this study are higher than those of coeval seawater (0.7090), collected from late-stage barite mineral vein of interpenetrative strata and a barite nodule bearing hypidiomorphic granular pyrite, which indicates that they might be related to the continental admixture. The study provides Sr isotopic evidence not only for the subma- rine hydrothermal exhalative genesis of Dahebian and Yup- ing barite deposits, but also for distinguishing the barite mineralization of late stage.

关 键 词：锶同位素 重晶石 沉积物 贵州 矿物 化学分析 

分 类 号：P578.71[天文地球—矿物学]