Analysis of REEs in magnetite monomineral from foot wall, through middle part to hanging wall of the Fenghuangshan copper polymetallic deposit shows increase of the averages of ∑REE in magnetite monomineral which are 11. 30× 10-6 , 29. 34 × 10-6 and 86. 15 × 10-6 respectively with average Seu values varied from 0. 62, 1. 23 to 2. 04. Comparison of REE contents of the deposit with those of the overlying granodiorite and the underlying limestone indicates that REE content of orebodies are mixture of those of magmatic rocks and strata in different proportions and ore materials are multiple sources. No obvious Eu anomalies of the rockbodies and the wallrocks demostrates the strong enrichment of Eu in the early ore fluids, and lower redox potential caused by the organic matter in the wallrocks. Accoding to the variograms of La/Sm-La and Ce/Yb-Eu/Yb, we infer that the igneous rocks in this region are dominantly formed by partial melting and separative crystallization during late mineralizations.%通过对铜陵凤凰山铜多金属矿不同部位的磁铁矿单矿物的稀土元素配分分析,发现从矿体的底板经过中部到顶板,磁铁矿中稀土元素总量平均值不断升高,依次为11.30×10-6,29.34×10-6和86.15×10-6,δ(Eu)平均值依次为0.62,1.23和2.04.与超覆于矿体之上的花岗闪长岩体和矿体下伏的围岩(灰岩)的稀土元素对比,认为矿体中稀土元素的来源为岩浆岩体和地层的不同比例混合,反映了成矿物质的多来源.岩体与围岩没有明显的铕异常,说明早期成矿流体对铕强烈的富集作用,且围岩中有机质造成氧化还原电位的降低.通过对La/Sm- La关系图和Ce/Yb- Eu/Yb变异图的分析,推测本区的岩浆岩以部分熔融为主,成矿晚期存在分离结晶现象.
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