Re-Os Isotope Study of Sulfide and Olivine Pyroxenite in the Limahe Nickle Deposit, Sichuan Province

详细信息   

• 责任者：Tao Yan (State Key Laboratory of Ore Deposit Geochemistry ; Institute of Geochemistry ; Chinese Academy of Sciences ; Guiyang 550002 ; China) ; Hu Ruizhong
• 刊名：Acta Geologica Sinica
• 出版年：2008
• 卷期：82(9)
• 关键词：镍矿 ; nickel ores ; 铼同位素 ; Re isotopes ; 锇同位素 ; Os isotopes ; 峨眉山 ; Emei Mountains
• 页码：p.1292-1304
• 图表：9 illus., 3 tables, 42 refs.
• 分类号：1001
• issnNo：ISSN0001-5717
• isbnNo：CN11-1951/P

摘要

The Limahe nickel deposit is one of the important PGE-poor Ni-Cu deposits in the Emeishan Large Igneous Province. This paper mainly analyzes Re-Os isotopic composition of various ore and rocks from the Limahe nickel deposit, discusses source magma, genesis of suphide, ore-forming mechanism and Re-Os isochron. The results show that different rock and rock types of the Limahe deposit are of different initial Os isotopic compositions. The analysis shows that heterogeneity of initial Os isotopic composition in the ore samples is attributed to the mixture of sulfide melt containing high radiogenic ¹⁸⁷Os and silicate melt containing low radiogeneic ¹⁸⁷Os at a different proportion. Comprehensive study reveals that the Limahe deposit originated from daughter magma which exsolved from deep magma.