摘要
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。
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.
出处
《大地构造与成矿学》
EI
CAS
CSCD
1997年第1期24-31,共8页
Geotectonica et Metallogenia
基金
中国科学院矿床地球化学开放研究实验室资助