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Re-Os dating on copper-nickel sulfide ores from the Baotan area, Guangxi, yielded an ore-forming age of 982±21 Ma (2σ), which demonstrates that copper-nickel sulfide deposits and their related mafic-ultramafic rocks occurred in the same period of time with the ophiolites in northeastern Jiangxi. Both of them are the products of collision-convergence between the Cathay-sian plate and Yangtze plate and the subsequent extensional environment. Calculation of the γOs of the 982 Ma copper-nickel sulfide ores and its correlation with Re/Os indicate that injection-type massive ores display lower γOs values (-15.6 to -8.2) and lower Re/Os ratios (0.32 to 0.43), while basal liquation-type ores have γOs= -27.9 to -7.3 and Re/Os=5.36 to 11.24. This suggests that these copper-nickel sulfide ores and their related mafic-ultramafic rocks were derived from a Re-depleted mantle source and that contamination with some crustal material occurred during their intrusion.
Re-Os dating on copper-nickel sulfide ores from the Baotan area, Guangxi, yielded an ore-forming age of 982 ± 21 Ma (2σ), which demonstrates that copper-nickel sulfide deposits and their related mafic-ultramafic rocks occurred in the the same period of time with the ophiolites in northeastern Jiangxi. Both of them are the products of collision-convergence between the Cathay-sian plate and Yangtze plate and the subsequent extensional environment. Calculation of the γOs of the 982 Ma copper-nickel sulfide ores and its correlation with Re / Os indicates that injection-type massive ores display lower γOs values (-15.6 to -8.2) and lower Re / Os ratios (0.32 to 0.43), while basal liquation-typeores have γOs = -27.9 to -7.3 and Re / Os = 5.36 to 11.24. This suggests that these copper-nickel sulfide ores and their related mafic-ultramafic rocks were derived from a Re-depleted mantle source and that contamination with some crustal material occurred during their intrusion.