Hadean–Neoarchean Crustal Evolution of the Northeastern North China Craton: Evidence Derived from the Zircon U–Pb–Hf Isotopes of Supracrustal Rock from the Jiapigou Terrane

The North China Craton (NCC), one of the oldest cratons worldwide, may provide information on the evolution and geodynamic processes of the early Earth, especially during the pre-Mesoarchean period. Many ancient zircons have been discovered in the Jiapigou terrane of the northeastern NCC on the basis of our recent studies, providing an excellent opportunity to trace the early crustal evolution trend of the NCC. Here, we present a detailed study of the petrography, mineralogy, zircon U–Pb dating and Lu–Hf isotopes of supracrustal rocks (biotite schist) obtained from the Jiapigou terrane. Geochronology combined with the internal structures and Th/U ratios of the zircons reveal that the zircons acquired from the supracrustal rock can be divided into the following two types: magmatic zircons and metamorphic zircons. Among the magmatic zircons, the youngest zircon age (2.49 Ga) is considered to represent the time at which the protolith of the supracrustal rock (i.e., Neoarchean) crystallized, whereas the others were likely captured or inherited from their magma sources. The zircon Hf isotopes reveal that unexposed Hadean–Paleoarchean crust (4.18–3.57 Ga) is present beneath the Jiapigou terrane, and its growth history can be traced back to the Hadean period. Moreover, the evidence derived from this and previous studies indicates that the Jiapigou terrane underwent two crustal recycling events (3.37–3.20 Ga and ~2.96 Ga) during the Paleoarchean, two crustal reworking episodes (2.53 Ga and 2.49 Ga) during the Neoarchean, and later metamorphism at 2.41 Ga. Thus, the Jiapigou terrane has undoubtedly recorded multiple episodes of early crustal growth and/or reworking that are similar to, but not limited to, those of the northern and southern margins of the NCC.