The Tulargen Cu-Ni sulfide deposit,whose discovery means a great breakthrough in Cu-Ni exploration in Xinjiang in the past ten years,is located in the eastern section of the Huangshan-Jingerquan ore belt.The Tulargen Cu-Ni deposit is a magmatic differentiation deposit related to mafic-ultramafic complex,which comprises three intrusions,namely complex Ⅰ,Ⅱ,Ⅲ,respectively.The hornblende pyroxene peridotite of complex Ⅰ is associated with abundant mafic enclaves,which include ore-bearing gabbro enclaves and plagioclasite enclaves without mineralization.Mafic enclaves and the host display different characteristics in such aspects as mineral species,types and intensities of alteration,contacts between minerals and forming sequence.There exists a distinct boundary,composed of squamiform chlorite,between the mafic enclaves and the host.The Harker diagram of major elements and figures of La,Nd,Zr,and Yb versus SiO2 have shown that samples of the Tulargen complex display a good correlation,whereas the mafic enclaves don't show such characteristics,which indicates that magmatic contamination played a significant role in the formation of the mafic enclaves.Nb/U and Ce/Pb ratios imply that,after crustal contamination,some elements of the mafic enclaves was mobilized and migrated by the late magmatic hydrous fluids.%新疆哈密图拉尔根铜镍硫化物矿床是东天山黄山-镜儿泉韧性剪切带上的一个典型岩浆熔离-贯入型矿床.在图拉尔根岩体中的角闪辉橄岩相中发育了一些基性包体,这些包体尺寸在几到几十厘米之间,岩性主要为辉长岩、斜长岩,辉长岩包体含矿性好,而斜长岩包体不含矿.通过岩相学观察发现,包体与寄主岩在矿物种类、含量、蚀变类型及程度以及矿物接触交代关系和生成顺序上存在较大的差异,并且,两者存在截然的接触边,该接触边以鳞片状绿泥石为主.哈克图解和SiO2与不相容元素La、Nd、Zr、Yb的相关性图解都显示图拉尔根基性超基性岩体样品具有很好的相关性,而包体样品则不具有明显的相关性,指示了岩浆混染作用在包体成岩中的重要作用.微量元素地球化学特征显示包体和图拉尔根岩体均具Nb、Ta亏损,这可能是陆壳混染作用的结果,或源区存在俯冲的洋壳物质.此外,包体中K、Pb、Sr、P含量非常高,暗示后期流体作用较强；包体的Nb/U、Ce/Pb值都更接近大陆地壳的值,这些都说明陆壳混染的可能性较高,或存在较强的流体迁移作用.
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