Genesis and metallogenic process of Tulargen large scale Cu-Ni sulfide deposit in eastern Tianshan area, Xinjiang
东天山地区图拉尔根铜镍硫化物矿床成因及成矿过程

Tulargen large scale Cu-Ni sulfide deposit is an important exploring discovery in eastern Tianshan in recent years. Study on the sections in the Tulargen gallery, the intrusion is mainly composed of amphibole peridotite, olivine pyroxenites, pyroxenites and gabbro from upper part to lower part, the chondrite-normalized REE patterns from different lithofacies show parallel lines, which indicates different lithofaces have the same magma source and experiencing similar evolution process. Tulargen deposit should have experienced deflection of occurrence, which can be inferred from the distribution and contacting relationship of different lithofaces, litho-geochemistry and regional tectonics also support this idea. Element-geochemistry and Sr, Nd, Pb isotopes prove that the primary magma source of Tulargen intrusion is from spinel-stable depleted mantle. Tulargen intrusion hosting enrichment REE patterns and MORB-type isotope features is possibly because the magma from partial melting of depleted mantle mixes with dehydration of subduction plate. The magma forming Tulargen intrusion has experienced weak contamination (<5%) of upper crust. PGE geochemistry indicates low partial melting (<16%) of depleted mantle leading to low PGE concentrations in Tulargen deposit, some PGE are still left in the mantle.