川西冷水箐Cu-Ni硫化物矿床的PGE和Re-Os同位素地球化学特征及成矿意义  

Geochemical characteristics of platinum-group elements and Re-Os isotope of the Lengshuiqing Cu-Ni sulfide deposit in western Sichuan Province and implications for mineralization

作　　者：苟体忠[1,2] 钟宏[1] 朱维光[1] 漆亮[1] 冷成彪[1,2] 吴孔文[1,2] 

机构地区：[1]中国科学院地球化学研究所矿床地球化学国家重点实验室,贵阳550002 [2]中国科学院研究生院,北京100049

出　　处：《岩石学报》2010年第11期3363-3374,共12页Acta Petrologica Sinica

基　　金：国家自然科学基金项目(40873028;40673031);中国科学院知识创新工程重要方向项目(KZCX2-YW-136;KZCX2-YW-111);矿床地球化学国家重点实验室专项经费资助

摘　　要：采用ICP-MS分析方法对冷水箐铜镍硫化物矿床矿石的PGE和Re-Os同位素地球化学研究表明,矿石的∑PGE较低,其值变化在7.91×10-9～56.9×10-9之间。矿石的Cu/Pd比值(9460～318040)远大于原始地幔的Cu/Pd比值,表明其原始岩浆在早期结晶过程中已经历了硫化物的熔离。矿石的Pd/Ir比值(2.57～112)变化较小,指示其大多数矿石属于岩浆型。(187Os/188Os)i比值和γOs(t)值变化较大,其值分别变化在0.1758～0.3620之间以及+44.0～+197之间,显示在成矿过程和岩浆侵位期间有较多地壳物质加入到成矿成岩系统。The platinum-group elements (PGE) and Re-Os isotopic geochemistry of copper-nickel sulfides ores from the Lengshuiqing deposit is studied using ICP-MS method. The total PGE contents (∑PGE) of the Lengshuiqing ores are quite low,ranging from 7.91×10-9 to 56.9×10-9. The Cu/Pd ratios (9460~318040) of the ores are much higher than that of primitive mantle,indicating that their parental magma might have undergone sulfide segregation at an early stage of crystallization. The Pd/Ir ratios (2.57~112) of the ores have a relatively narrow range,consistent with magmatic genesis of the deposit. Both ( 187Os/188Os)i and γOs(t) values are quite variable,ranging from 0.1758 to 0.3620 and +44.0 to +197,respectively,suggesting that abundant crustal material was mixed with the Cu-Ni sulfide ore system during magma ascent and the ore-forming processes.

关 键 词：铜镍硫化物矿床 RE-OS同位素 铂族元素 冷水箐 

分 类 号：P618.41[天文地球—矿床学]