中文摘要：

云南朱布镁铁-超镁铁岩体赋存中型铜镍铂族元素矿床, 侵位于元谋群片岩和花岗片麻岩中, 岩体垂直分异明显, 自下而上为橄榄岩、橄辉岩、辉石岩、辉长岩等相带。矿体以底部“边缘矿”为主, 上部有呈透镜状产出的少量“上悬矿”。本文报道了朱布岩体主元素、微量元素、铂族元素（PGE）和Sr-Nd同位素组成新的测试结果。分析表明朱布岩体具有拉斑玄武质岩浆分异演化趋势, 富集LREE的分布模式, 弱的Nb异常和较明显的Sr负异常, 并与峨眉山大火成岩省（ELIP）苦橄岩相类似, 暗示两者可能存在成因上的联系。朱布岩体的铂族元素相对分布模式为“Pt-Pd”富集型, 原始地幔标准化曲线向左陡倾。较高的（87Sr/86Sr）i （0.7096~0.7107）和较低的εNd（t） （-3.1~ -2.3）, 表明朱布岩浆受到了地壳物质不同程度的混染。通过岩浆演化过程反演, 得出其母岩浆性质为苦橄质, 并估算地壳混染程度在3%~20%之间, 发现在R （岩浆与熔离硫化物的比例）值为1000~5000时比较吻合朱布样品中硫化物的实际测定值, 证实了朱布岩体可能为开放系统的岩浆房, 经过多级富集过程, 先熔出的硫化物从后续多期次岩浆中吸收了大量PGE, 岩浆房中同时存在堆晶和岩浆演化, 分别形成了底层橄榄岩和上部的辉长岩, 中间过渡为橄辉岩和辉石岩。

英文摘要：

The mineralized complex which host Zhubu medium-sized Cu-Ni-PGE deposit is a mafic-ultramafic intrusion, intruded the schists and granitic-gneisses of Yuanmou Group. This intrusion is vertically well differentiated with peridotite, olivine pyroxenite, pyroxenite and gabbros from bottom to the top. The ore bodies are mainly composed of “edge ores”, a few “suspended ores” which occur as lenses located at the upper part. This paper provided new test results on major elements, trace elements, platinum-group elements （PGE） and Sr-Nd isotopes for some rocks and ores in the intrusion. The major and REE elements of the rocks show a tholeiitic evolution trend. The samples enrich in LREE and indicate a marked and weak negative anomalies for Sr and Nb, respectively. The patterns of REE and trace elements are similar to those of picrites in Emeishan Large Igneous Province （ELIP）, suggesting a genetic link between the Zhubu intrusion and picrites in ELIP. Primitive mantle normalized chalcophiles elements patterns of the Zhubu sulfide ores show enrichments in Pt and Pd compared to other elements. The higher （87Sr/86Sr）i （0.7096~0.7107） and the lower εNd（t） （-3.1~ -2.3） show Zhubu magma experienced variable degree of crustal contamination. The inversion of magma evolution show that the primary magma is a picritic melt. By estimation, the magma experienced 3%~20% crustal contamination. When the R factor （the mass ratio between silicate magma and sulfide liquid） fall into the range of 1000 to 5000, it is close to the actual measured value of the sulfide in Zhubu samples, indicate that it maybe a magma conduit in an open system. Successive pulses of new magma passing through the conduit and upgraded the previously segregated sulfide in PGE by a multistage upgrading process. The mineral cumulus and magma evolution also exit in the chamber, formed peridotite at the bottom and gabbros on the top, respectively, with pyroxenite and olivine- pyroxenite in between.