五台花岗绿岩带中王家会岩体构造型式及定位机制
TECTONIC FORM AND EMPLACEMENT MECHANISM OF THE WANGJIAHUI INTRUSION IN THE WUTAI GRANITE-GREENSTONE BELT
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摘要: 晚太古代五台花岗绿岩带中的王家会岩体,呈北东向延伸的不规则椭圆形,岩体中普遍发育片麻理和矿物定向拉伸线理。片麻理的迹线型式如同一个水平放置的长水滴的横断面,岩体中大量自形钾长石斑晶的出现,流动分异构造的存在,以及矿物弱晶内变形的特点都指示了岩体的内部构造主要是岩浆流动成因。围岩至少经历了三期变形和两期变质。岩体的内部构造系统明显地截切了围岩构造系统。两者之间不存在强烈的变形带。这显示了岩体的被动侵位的特征,王家会岩体的形态受深部走滑作用形成的张裂空间的控制。Abstract: In the paper the authors consider the emplacement of the Wangjiahui intrusion to be tec-tonic and passive and related to the strike slips of the late Late Archean Fuping and Heng-shan blocks at deep levels in the terminal stage of collision of the two blocks.