新街镁铁—超镁铁侵入体的铂族元素地球化学特征

采用镍硫试金预处理中子活化分析方法，系统测定了新街层状侵入体镁铁－超镁铁岩和与其有成因联系的玄武岩及正长岩的铂族元素含量，探讨了岩浆作用过程中铂族元素的地球化学行为。结果表明，新街岩体的铂元素分异特征与布什维尔德等铁质超镁铁岩相似，而明显不同于科马提岩和阿尔卑斯型橄榄岩，二叠系峨眉山玄武岩的铂族元素分异特征与新街岩体相似，再次证实二者为同源岩浆分异产物。

GEOCHEMISTRY OF PLATINUM GROUP ELEMENTS IN MAFIC-ULTRAMAFIC ROCKS FROM THE XINJIE INTRUSION

The contents of platinum group elements in mafic-ultramafic rocks from the Xinjie layered intrusion and in basalts and syenites petrogenetically related to the layered intrusion have been determined using neutron activation analysis after a nickel sulphide fire assay preconcentration. The geochemical behavior of platinum group elements during magmatic activation is discussed. It turns out that the distribution of platinum group elements for the Xinjie layered intrusion is similar to that for ferruginous ultramafic rocks in Bushveld and so on, but is different from that for komatiite and Alpine-type peridotite. The distribution of platinum group element for the Xinjie layered intrusion is also similar to that for the Emei Shan basalt. It is proved that the original magma forming the Xinjie layerd intrusion is similar to the original Emei Shan basaltic magma.