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峨眉火成岩省内带出露数十个含Ni-Cu-铂族元素(PGE)硫化物矿床(或矿化)的镁铁质-超镁铁质侵入岩体.根据铂族元素(PGE)含量的不同,这些岩浆硫化物矿床可分为Ni-Cu型(如力马河和清水河)、Ni-Cu-PGE型(如清矿山和黄草坪)和PGE型(如金宝山和杨合武).不同类型含矿岩体的橄榄石电子探针分析表明,除了清矿山岩体少数几个橄榄石晶体属于镁橄榄石外(Fo90.1～Fo93.1),其余均为贵橄榄石(Fo76.8～Fo89.6).不同矿化类型的岩体的橄榄石成分差异明显.Ni-Cu型硫化物含矿岩体的橄榄石Fo为77～87,Ni含量变化范围为(976～2176)×10-6.Ni-Cu-PGE型硫化物含矿岩体的橄榄石Fo为80～86,Ni含量范围为(1024～2543)×10-6.PGE型硫化物含矿岩体的橄榄石Fo为78～84,Ni含量在(776～1755)×10-6之间变化.清矿山Ni-Cu-PGE型硫化物含矿岩体橄榄石具有高Fo(最高达93.1)和CaO含量(0.245%～1.14%)、以及非常低的Ni(266×10-6)的特征,可能是同化混染作用的结果.利用力马河岩体最高Fo含量的橄榄石成分计算表明,母岩浆是高镁苦橄玄武质岩浆.橄榄石分离结晶和硫化物熔离模拟显示:Ni-Cu型矿化侵入体母岩浆经历了最广泛的硫化物熔离(～0.1%),Ni-Cu-PGE型侵入体次之,大约为0.06%,而PGE型侵入体母岩浆硫化物熔离程度最低(～0.02%).早期结晶的橄榄石晶体与间隙硅酸盐熔浆之间再平衡过程是橄榄石成分变化的原因.
In Emei igneous province, there are dozens of mafic-ultramafic intrusions containing Ni-Cu-PGE sulfide deposits (or mineralization) .According to the content of PGE , These magmatic sulfide deposits can be divided into Ni-Cu type (such as Lima River and Qingshuihe River), Ni-Cu-PGE type (such as clear mines and yellow turfgrass) and PGE type (such as Jinbaoshan and Yanghewu) The olivine electron probe analysis of the type of ore-bearing rock mass shows that except for a few olivine crystals in the QingMen rock mass belonging to forsterite (Fo90.1 ~ Fo93.1), the rest are peridotite (Fo76.8 ~ Fo89.6) .The olivine contents of rock masses with different mineralization types are obviously different.The peridotite Fo of Ni-Cu sulphide ore-bearing rock mass is 77 ~ 87 and the Ni content is (976 ~ 2176) × 10-6. The olivine Fo of Ni-Cu-PGE type ore-bearing rock mass is 80 ~ 86 and the Ni content ranges from (1024 ~ 2543) × 10-6. The olivine Fo ranged from 78 to 84, and the Ni content varied from (776 to 1755) × 10-6. The olivine content of the Ni-Cu-PGE sulphide ore-bearing rock mass in Qingling mines is characterized by high Fo (up to 93.1) and CaO content 0.245% ~ 1.14%), as well as the very low Ni (266 × 10-6) Which is the result of assimilation of contamination.Using olivine composition of the highest fo content in the Limahe rock mass indicates that the parent magma is a high Mg bitter olivine magma.The separation crystallization of olivine and the sulfide ionization simulation show that Ni- The Cu-type mineralized intrusions experienced the broadest sulfide ionization (~ 0.1%) in the parent magmatic intrusions, followed by the Ni-Cu-PGE intrusive species, which was about 0.06%, while the PGE intrusive parent magma sulfide melted (~ 0.02%). The reason for the change of olivine composition is the process of re-equilibration between early crystalline olivine crystals and interstitial silicate slurries.