冲绳海槽Jade热液区块状硫化物中流体包裹体的氦、氖、氩同位素组成  

He, Ne and Ar isotope compositions of fluid inclusions in massive sulfides from the Jade hydrothermal field, Okinawa Trough

作　　者：曾志刚[1] 秦蕴珊[1] 翟世奎[2] 

机构地区：[1]中国科学院海洋研究所,山东青岛266071 [2]中国海洋大学海洋地球科学学院,山东青岛266003

出　　处：《海洋学报》2003年第4期36-42,共7页

基　　金：国家重点基础研究发展规划项目课题资助项目(G2000046701);国家自然科学基金(40176020)

摘　　要：对冲绳海槽Jade热液区块状硫化物中流体包裹体的氦、氖和氩同位素组成进行了测定,流体包裹体的~3He/~4He比值为(6.2～10.1)Ra,均值为7.8Ra,与大洋中脊玄武岩一致[~3He/~4He≈(6～11)Ra],^(20)Ne/^(22)Ne比值为10.7～11.3,明显高于大气值(9.8),而^(40)Ar/^(36)Ar比值的变化范围在287～334之间,接近大气值(295.5),这些结果表明,块状硫化物中热液流体捕获的稀有气体是地幔和海水源组分混合的产物,且流体包裹体中的氦主要来自地幔,氖和氩主要来自海水。Helium, neon and argon isotope compositions of fluid inclusions have been measured in massive sulfide samples from the Jade hydrothermal field at the central Okinawa Trough. Fluid-inclusion 3He/4He ratios are between 6.2 and 10.1 times the air value (Ra), and with a mean of 7.8 Ra, which are consistent with the mid-ocean ridge basalt values [3He/4He≈(6 - 11 )Ra]. Values for 20Ne/22Ne are from 10.7 to 11.3, which are significantly higher than the atmospheric ratio (9.8). And fluid-inclusion 40Ar/36Ar ratios range from 287 to 334, which are close to the atmosperic values (295.5). These results indicate that the noble gases of trapped hydrothermal fluids in massive sulfides are a mixture of mantle-and seawater-derived components, and the helium of fluid inclusions is major from mantle, the Ne and Ar isotope compositions are major from seawater.

关 键 词：Jade热液区 块状硫化物 流体包裹体 氦 氖 氩 同位素 海洋地球化学 

分 类 号：P736.44[天文地球—海洋地质]