云南鸡街碱性超基性岩杂岩体岩浆过程模拟

在已有云南鸡街碱性超基性杂岩体地质、地球化学资料基础上，本文利用岩石学混合计算等方法对杂岩体源区成分、结晶分异过程进行模拟。结果表明，鸡街杂岩体来源于亏损地幔；岩体中相对早期碱性超基性岩（主体岩石：霞霓纳辉岩、霓霞岩和磷霞岩）为很少或没有受到上部地壳物质污染的幔源岩浆结晶分异作用产物；晚期碱性中性岩（脉岩：钠霞正长岩和霓辉钠长斑岩）为幔源岩浆（与碱性超基性岩同源）演化过程中发生岩浆液态不混淆作用产物。

MODELLED THE MAGMATIC PROCESSES OF JIJIE ALKALINE-ULTRABASIC INTRUSIVE COMPLEX, LUFENG, YUNNAN

On the base of studies in geology and geochemistry of Jijie alkaline-ultrabasic intrusive complex, Lufeng, Yunan province. This paper, using the methods of petrological mixing calculating and others, modelled the composition of mantle-source rocks and fractional crystallization of complex.The results of modelling Calculating showed that the mantle-source rocks of the Jijie complex are obviously depleted in incompatible elements, earlier alkaline- ultrabasic rocks in tha complex (melteigites, ijolites and urtites) were the products 0f fraction 41 crystallization of mantle-derived which has not been or rarely been contaminated by the crust, later alkaline-mediosilicic rocks (agpaitic nepheline syenites ) and aegirine-albitophyres) were the products of liquid immiscibil1ty of mantle-derived magma (affinlty with alkaline-ultrabsic rocks) during the processes of evolution.