摘要
尽管阿尔金南缘长沙沟-清水泉一带在空间上彼此分隔的4个镁铁-超镁质岩体（或岩体群）在岩石学、岩相学、地球化学上存在着差异,但它们的形成时代均为中奥陶世（465 M a左右）。其中,分布于阿尔金南缘主断裂南侧的清水泉南—长沙沟中段—黄土泉的岩体,超镁铁岩（包括纯橄岩-橄榄岩-辉橄岩-橄辉岩）中的橄榄石Fo值较高（变化于95-85）,且自东向西呈现非常有规律的递减;而北侧的清水泉北岩体辉橄岩中橄榄石的Fo值较低（变化于81~79）。结合各岩体的岩石地球化学特征和岩浆演化过程及橄榄石中N i的含量变化规律,对这些杂岩体形成的地质背景和Cu-N i-PGE含矿可能性作简要讨论。
Although the four mafic-ultramafic intrusions in the Changshangou to Qingshuiquan area, Altyn Tagh, have the differences in petrology, petrography and geochemistry, they all formed in MiddleOrdovician, about 465Ma. Thereinto, the forsterite contents （Fo） in olivine of the Southern Qingshuiquan （SQ）, Middle section of Changshagou （MC） and Huangtuquan （HT） intrusion, located in the south sideof southern Altyn fault, vary from 95 to 85, and decrease progressively from east to west, that is higher than that （81-79） in olivine of the Northern Qingshuiquan （NQ） intrusion which is located in the north side of southern Altyn fault. According to the geochemical characteristics, magma evolution procedure and the relations between Nickel content and Fo in olivine, has been discussed in the geological background and potential magmatic Cu-Ni-PGE mineralization of these mafic-ultramafic intrusions.
出处
《西北地质》
CAS
CSCD
2010年第4期18-24,共7页
Northwestern Geology
基金
国家十一五科技支撑计划新疆305项目(2006BAB07B03-02)
中国地质调查局项目(11212010786006)
