个旧印支期玄武岩稀土元素特征

Features of Rare Earth Elements of Basalt of Indo-Chinese Epoch in Gejiu

关于个旧锡多金属矿床成因,过去多数人持"燕山期花岗岩岩浆期后气化热液成矿"观点。文章作者认为个旧锡多金属矿床的形成和印支期玄武岩有很大关系,作者分析了个旧锡多金属矿区的印支期玄武岩的稀土元素特征。结果表明,三期火山活动的稀土配分模式都呈右倾斜曲线,为轻稀土弱富集型。从早到晚,三期火山岩的∑REE分别为169.29,157.99和239.49。

It had been believed that the genesis of tin-polymetallic deposits in Gejiu were granitic mineralization of the Yanshanian epoch by most researchers for a long time. The authors of this paper believe that genesis of tin-polymetallic deposits in Gejiu are related with basic volcanism of the Indo-Chinese epoch. This paper analyses features of rare earth elements of basalt of the Indo-Chinese epoch in Gejiu area. The results include ： （ 1 ） The REE distribution pattern of three epochs of basalts in Gejiu inclines to the right,representing weak enrichment in light rare earth elements. （2）From the early to the late,the ∑REE of three epochs of basalts in Gejiu are 169.29,157.99 and 239.49 respectively.