Xingdi III magmatic body is located in Kuruktag area in the northeastern margin of Tarim Basin, with an exposed area of about 0.5km2. The rock types are mainly olivine pyroxenite, websterite, monopyroxenite, gabbro and so on, Which belongs to tholeiite series. The gabbro and olivine have low REE content (∑REE=39.58×10-6~149.39×10-6), enriched light rare earth elements [(La/Yb)N=3.83~9.91] and large ion lithophile elements (Rb, Ba, K, Sr), depleted high field strength elements (Nb, Ta, P, Ti). δEushows weak positive anomalies. Petrographic and geochemical characteristics indicate that olivine crystallization occurs during magma migration. The primary magma is magnesia-rich tholeiite, and the magma is assimilated with crustal materials during its ascent. There are many similarities between Xingdi III magmatic body and Jinchuan magmatic body, and copper-nickel mineralization has been found on the surface of Xingdi III magmatic body. There are good prospecting prospects.%提 要 新疆尉犁县兴地Ⅲ号岩体位于塔里木盆地东北缘的库鲁克塔格地区,出露面积约为0.5km2.岩石类型主要为橄榄辉石岩、二辉辉石岩、单斜辉石岩、辉长岩等,属拉斑玄武岩系列.岩体辉长岩和橄辉岩的稀土元素含量较低(∑REE为39.58×10-6～149.39×10-6),富集轻稀土元素[(La/Yb)N=3.83~9.91]和大离子亲石元素(Rb、Ba、K、Sr),亏损高场强元素(Nb、Ta、P、Ti),δEu显示弱的正异常.岩相学及地球化学特征表明,岩浆运移过程中发生了橄榄石的分离结晶作用,原生岩浆为富镁拉斑玄武岩,岩浆上升过程中遭受了地壳物质的同化混染和流体交代.兴地Ⅲ号岩体与金川岩体具有很多相似之处,而且岩体地表已见铜镍矿化,具有较好的找矿前景.
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