晋北早前寒武纪变质岩区构造相研究  

Tectonic Facies of Early Precambrian Metamorphic Terrance,Northern Shanxi province

作　　者：郭景林[1] 米广尧[2] 范林森[1] 魏俊浩[3] 

机构地区：[1]山西省煤炭工业厅资源地质局,太原030045 [2]山西省地质调查院,山西榆次0306003 [3]中国地质大学(武汉)资源学院,武汉430074

出　　处：《华南地质与矿产》2011年第3期221-230,共10页Geology and Mineral Resources of South China

摘　　要：晋北地区出露有不同层次的地壳,是研究构造相最理想的地区之一。本文以构造分析为主线,结合当前地壳流变学研究进展,对该区早前寒武纪构造特征进行了分析,初步建立了早前寒武纪地质事件序列。提出了该区北部(大同-集宁)麻粒岩相变质岩代表下地壳的物质组成,中部(恒山)中深变质岩代表典型的中下地壳过渡带的特征(早前寒武纪一个重要的软弱层),南部(五台山)角闪岩相变质的五台岩群具中地壳构造特点,而绿片岩相变质的滹沱群代表上地壳构造特征的观点。根据不同层次的褶皱、断裂、布丁化岩石及同构造分泌结晶脉的宏观地质特征和与其相关的微组构特征,结合当前实验研究成果,提出了变质岩构造相新的划分方案,对该区进行了构造相的划分。在此基础上对该区构造相相变进行了探讨。Northern Shanxi province is considered to be one of the most popular places for the tectonic facies researches due to the various structural characters at different crust levels.In the present study,the relative order of geological events in Early Precambrian was established using the structural analysis combined with the research progress of geological rheology.The results are as follows： the rocks of the lower crust in Datong-Jining areas are believed to consist chiefly of granulite-facies metamorphic rocks;the high grade metamorphosed crustose rocks in Hengshan Mt.may represent the transitional zone of mid-lower crust;the amphibolite facies metamorphic rocks are mainly in the southern areas（Wutai Mt.）;the greenschist facies metamorphic rocks are characterized by the presence of upper crust in Hutuo group.In addition,based on the different geological characters of fold,fracture,pudding of the rock and syntectonic crystallization,we provide some references for analyzing the tectonic facies and the structural phase transition in the Northern Shanxi province.

关 键 词：构造相 构造相相变 流变学分层 前寒武纪变质岩 晋北地区 

分 类 号：P534.1[天文地球—古生物学与地层学]