小秦岭早元古代变质侵入体的厘定及地质意义

箭峪岭早元古代闪长质杂岩体为小秦岭地区最早的侵入体。岩石类型为闪长岩、石英闪长岩、花岗闪长岩，不具TTG岩石类型特征，经中元古代中条构造热事件发生区域动力热流变质作用，岩石从块状—弱片麻理—强片麻理均有发育，变质达高绿片岩相。闪长质岩浆演化为双峰式，岩石为钙碱性系列。据侵入关系、同位素年龄分析等，其侵入时代为早元古代。

THE DETERMINATION AND ITS GEOLOGICAL SIGNIFICANCE OF THE METAMORPHIC INTRUSIVE OF EARLY PROTEROZOIC SUBERA IN XIAOQINLING

Jianyuling dioritic complex, formed in the early proterozoic,is the oldest intrusive in Xiaoqinling region. It was composed by diotite,quartz diorite and granodiorite, which are different from the TTG type. Having been influenced by the regional dynamo-thermal metamorphism of zhongtiao orogeny,the complex are in block,slightly geneissic and highly gneissic,and reached to hight-greenschist facies. The evolutional modle of the dioritic magma is in double-peaking,so it should belong to the calc - alkaline magma system. The fact of intrusive contact, the istopic age and the other material show that the complex was intruded in the early Proterozoic.