Discovery of Neoarchean unconformity and its implication for continental cratonization of North China craton  

作　　者：钱祥麟 李江海 

出　　处：《Science China Earth Sciences》1999年第4期399-407,共9页中国科学（地球科学英文版）

基　　金：Project supported by the National Natural Science Foundation of China (Grant Nos. 49132070, 49302035, 49572140).

摘　　要：An ancient unconformity event is identified within the granulite-facies province of North China, which is marked by the boundary between the overlying khondalite series (KS) and the basement grey gneiss complex (BGGC) , REE patterns of KS suggest that their protoliths are mature sediments. As documented by isotopic ages and metamorphic P-T-t paths, KS is originally deposited after the basement complex formed. Furthermore, the BGGC was overprinted by the metamorphic event associated with the KS. The binary structure of KS-BGGC is well preserved in the western part of North China craton (NCC) , and it is structurally truncated and overlain by the Palaeoproterozoic Wutai rift, which suggests that the unconformity occurred in the Neoarchean, and represents the major tectono-thermal episodes of the Neoarchean continental cratonization of NCC.An ancient unconformity event is identified within the granulite-facies province of North China, which is marked by the boundary between the overlying khondalite series (KS) and the basement grey gneiss complex (BGGC). REE patterns of KS suggest that their protoliths aM mature sediments. As documented by isotopic ages and metamorphic P-T-t paths, KS is originally deposited after the basement complex formed. Furthermore, the BGGC was overprinted by the metamorphic event associated with the KS. The binary structure of KS-BGGC is well preserved in the western part of North China craton (NCC), and it is structurally truncated and overlain by the Palaeoproterozoic Wntai rift, which suggests that the unconformity occurred in the Neoarchean, and represents the major tectono-thermal episodes of the Neoarchean continental cratonization of NCC.

关 键 词：NEOARCHEAN CRATONIZATION KHONDALITE series grey GNEISS UNCONFORMITY event. 

分 类 号：P54[天文地球—构造地质学]