福建建宁西部上太古界天井坪组(Ar_2t)地质特征  

Geological Characteristics of Upper-Archaeozoic Tianjingping Formation Ar_2t in Western Jianning,Fujian Province

作　　者：付树超 陈觉民[1] 林文生 

机构地区：[1]福建省区域地质调查队

出　　处：《福建地质》1991年第2期103-113,共11页Geology of Fujian

摘　　要：福建建宁西部广泛出露低角闪岩相变质岩系,前人把它划分为丁屋岭组(Z_1dn)和上震旦统(Z_2)。经1∶5万区域地质调查,作者新建了上太古界天井坪组(Ar_2t),划分出下、上两个岩性段,该组厚度大于855.3m,其原岩属古岛弧型火山复理石相建造,上段斜长角闪岩 Sm-Nd 全岩等时线年龄为2682±148Ma,被前加里东期变质石英闪长岩侵入。Wide outcropping of metamorphic rocks of low hornblendite facies which were formerly defined as Dingwuling Formation (Z_1dn) and Upper Sinian (Z_2) can be found in western Jianning of Fujian Province.The strata are now designated as upper-Archaeozoic Tianjingping Formation which possess two lithological members with a thickness over 855.3m,the original rock of ancient island-arc type volcanic flysch formation,a Sm-Nd whole rock isochronous age of 2 682±148Ma for plagioclase- hornblendite in upper menber,and intrusion of pre-Caledonian metamophic quartz-diorite in accor- dance with achievements of recent 1:50000 regional geological surveying.

关 键 词：太古代 天井坪组 地质特征 福建 

分 类 号：P534.2[天文地球—古生物学与地层学]