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兴地Ⅱ号铜镍矿床为岩浆多期次分异、侵位形成的基性—超基性杂岩体;本文通过对兴地辉长岩进行SIMS锆石U-Pb精确测年,获得206pb/238U加权平均年龄为737±2 Ma,该数据表明兴地Ⅱ号杂岩体形成于南华纪,并非形成于中元古代.塔里木北缘广泛发育的碳酸岩、基性—超基性岩和双峰式火山岩,为Rodinia超大陆长期的和持续的裂解产物.“,”The Xingdi No.2 complex is composed mainly of basic and partly of ultrabasic rocks.Copper and nickel mineralization occurs in both interior and exterior of the complex.A gabbro sample yielded a SIMS U-Pb zircon age of 737±2 Ma (MSWD =0.038,95％ confidence level),which indicates that the Xingdi complex formed during the Nanhua period rather than Mesoproterozoic time.A number of studies suggest that there were three episodes of mantleplume activities,at ca.830 ～ 800 Ma,780 ～ 740 Ma and 650 ～ 630 Ma respecitively,during the break-up of supercontinent Rodinia within in the Tarim.The Xingdi intrusive suite formed in a Neoproterozoic continental rift setting,possibly related to mantle plume activities that led to the breakup of the Rodinia supercontinent.