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

Abstract

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.