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金宝山是中国目前发现的最大的独立铂钯矿床,该岩体基性程度高,主要由橄榄石、单斜辉石组成,含大量铬铁矿〔w(Cr)约为0.5%〕。铂钯矿石呈稀疏浸染状,硫化物含量少,高铂族元素、低铜镍含量。矿体与超基性围岩界线不明显,且二者具有相似的微量、稀土元素参数和微量、稀土、铂族元素标准化配分模式,表明两者的原始岩浆具有相似的性质。超基性围岩具有高的Pd/Ir、Ni/Cu比值和Pb负异常,相反,铂钯矿石显示为低的Pd/Ir、Ni/Cu比值和Pb正异常,两者具有相似的Cu/Pd、Cu/Pt比值(≤原始地幔值),表明铂钯矿石形成于地幔柱S低度饱和环境,超基性围岩可能形成于S饱和/不饱和的地球化学界面。铂族元素地球化学的差异表明含少量富铂族元素的硫化物的含矿岩浆可能注入于稍前侵入的、且未完全固结的超基性围岩中,形成似层状矿体。峨眉地幔柱早期硫低度饱和、融离出少量硫化物以及铂族元素在硫化物/硅酸盐相中极高的分配系数是导致金宝山矿石富铂钯、贫铜镍的根本原因。金宝山是极少有的全岩体Cu/Pd、Cu/Pt值均小于原始地幔值的矿床,表明该岩体的岩浆经历了硫化物富集铂族元素的过程,推测靠近峨眉地幔柱喷发中心的基性-超基性岩体是寻找铂族元素矿床最佳远景区之一。
Jinbaoshan is the largest independent Pt-Pd deposit found in China. The rock mass is highly basic and consists mainly of olivine and clinopyroxene with a large amount of chromite [about 0.5% w]. Platinum-palladium ore was sparsely disseminated, sulfide content, high platinum group elements, low copper and nickel content. The boundaries between ore bodies and ultramafic rocks are not obvious, and the two have similar trace and rare earth elements parameters and the normalized distribution patterns of trace, rare earth and platinum group elements, indicating that the two magmas have similar properties. The ultramafic rocks have high Pd / Ir, Ni / Cu ratios and negative Pb anomalies. On the contrary, platinum-palladium ores show low Pd / Ir, Ni / Cu ratios and positive Pb anomalies, Pd and Cu / Pt ratios (≤ original mantle values), indicating that platinum-palladium ores formed in the low saturation of mantle plume S and ultramafic rocks may form at S-saturation / unsaturated geochemical interfaces. The differences in PGGE geochemistry indicate that ore-bearing magmas containing a small amount of sulfide-rich sulfide may be infiltrated in previously infiltrated and unconsolidated ultrabasic rocks to form laminar-like ores. Emei mantle plume early saturation of the low sulfur, a small amount of sulfide and the separation of platinum group elements in the sulfide / silicate phase of the high distribution coefficient is the cause of Jinbaoshan ore platinum-rich palladium, the basic reason for poor copper-nickel. Jinbaoshan is a rare deposit with Cu / Pd of all rock mass and Cu / Pt value less than the original mantle value, indicating that the magma of this rock body experienced the process of sulphide enrichment of platinum group elements and it is presumed that near the Emei mantle plume The basic mafic-ultramafic rock mass is one of the best prospects for finding platinum group element deposits.