【作者】 陶琰； 罗泰义； 高振敏； 朱丹；

【Author】 Tao Yan, Luo Taiyi, Gao Zhenmin, Zhu Dan(Open Laboratory of Ore Deposit Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences,Guiyang 550002, China)

【机构】 中国科学院地球化学研究所矿床地球化学开放实验室；

【摘要】 金宝山超镁铁岩体由基性岩浆深部分异形成,以含大量橄榄石的“晶—糊”体系侵位。在根据成岩机制概算原始岩浆微量元素含量的基础上,通过模式计算,表明原始岩浆较低的不相容微量元素总量但强不相容元素及轻稀土元素的相对富集型式不可能由现有原始地幔或亏损地幔模型的单一源区熔融或融体混合作用形成,原始岩浆起源于类似OIB源的地幔柱高程度熔融,熔融程度在19%左右。更多还原

【Abstract】 The Jinbaoshan intrusion, situated in Midu county, Yunnan, host the largestindependent PGE deposits of China. This small ultramafic intrusion is a cumulate of basic magma in a form of "crystal-mush" by Ol fractionation in magma chamber. Based on the estimate of trace elements content of primary magma according the mechanism of magma evolution, modeling of several kind of possible mantle melting had been attempted in this paper. For lower incompatible trace element content but significant fractionation pattern in order of elements incompatibility, The modeling shows that the primitive magma of Jinbaoshan intrusion cann’t be originated by melting of either primitive mantle (PM) or N-MORB source(DM), nor any mixing of the two. But it can reconcile with modeling of high degree partial melting (about 19%) of the source of OIB. So, the primitive magma of Jinbaoshan Ultramafic Intrusion originated from mantle plume.更多还原