华北克拉通阜平杂岩的深熔和混合岩化作用  

Anatexis and migmatization of the Fuping Complex,North China Craton

作　　者：任留东[1] 耿元生[1] 杜利林[1] 王彦斌[1] 刘平[1] 郭进京[2] 

机构地区：[1]中国地质科学院地质研究所,北京100037 [2]天津城市建设学院,天津300384

出　　处：《岩石学报》2011年第4期1056-1066,共11页Acta Petrologica Sinica

基　　金：国土资源大调查项目(1212010811033;1212010611802和1212010811048);国家自然科学基金项目(41072053)联合资助

摘　　要：华北克拉通的阜平杂岩长英质岩石中常产出显著的浅色体、岩脉和花岗岩侵入体,并形成广泛的混合岩化作用。通过矿物自形晶的形成、黑云母向角闪石的转换和大量钠长石净边的出现以及其它与熔体活动有关结构的分析,浅色脉体和混合岩化作用的发生与外来熔体的注入有关。在长英质片麻岩中可出现明显的熔体注入,在一些不易片理化的岩石如石英岩中亦可形成浸染状熔体渗入。熔体汇集可形成浅色体、岩脉,直至花岗岩侵入体。而深熔作用本身形成熔体的作用在本区几乎可以忽略不计。在遭受渗透式混合岩化作用的过程中,岩石成分发生了改变,形成开放系统。随着渗透熔体的结晶,可形成一些岩浆锆石,在副片麻岩中则很容易被当作碎屑锆石。Most of the quartzofeldspathic rocks in the Fuping Complex of the Trans-North China Orogen bear a large quantity of leucocratic veins,dykes and granitic intrusions.Magmatism or melt activity was responsible for the ubiquitous migmatization of the complex.Migmatization can be manifested with prominent melt injections in the felsic gneisses and faint dispersed melt crystallization in the competent quartzite of the Wanzi Series metasedimentary rocks.Melt infiltration migmatization can be deduced through euhedral crystallization of feldspar and quartz,transition of biotite to amphibole,albite rims and rare occurrence of partial melting reactions.In the process of melt infiltration migmatization,the rock composition was changed and the system was open in chemistry.Due to crystallization of the infiltrated melt,some zircons of magmatic feature may be formed and can be easily mistaken as detrital zircons in metasedimentary rocks.

关 键 词：熔体 反应结构 渗透式混合岩化 深熔作用 阜平杂岩 

分 类 号：P618.51[天文地球—矿床学]