Depositional age and provenance analysis of theWufoshan Groupin the southernNorth China Craton: Constraints from detrital zirconU–Pbgeochronology andHfisotopes

Abstract

The Late Precambrian Wufoshan Group from the southern North China Craton (NCC) is significant for its contribution to our understanding of the Precambrian evolution of the NCC, which consists of the Lower Ma'anshan, Upper Ma'anshan, Puyu, Luotuopan, and Hejiazhai formations. Detrital zircon U–Pb ages and Lu–Hf isotopes from the Puyu, Luotuopan, and Hejiazhai formations are used in this study to constrain the depositional age and provenance of the Wufoshan Group and crustal evolution of the NCC. The Puyu Formation is characterized by detrital zircon U–Pb age populations of ~2.13 Ga and ~2.50 Ga, similar to the Lower–Upper Ma'anshan formations from the literature. The Luotuopan Formation exhibits age populations of 1.85–2.18 Ga and 2.28–2.98 Ga, with mainly negativeεHf(t) values and scattered positiveεHf(t) values clustering at two groups of 2.48–2.52 Ga and 2.64–2.97 Ga. The Hejiazhai Formation displays age populations of 0.98–2.00 Ga and 2.51–2.79 Ga with mainly positiveεHf(t) values, whose depositional age is constrained as Neoproterozoic era by the youngest graphical detrital zircon age of 976 ± 20 Ma. Provenance studies indicate that the Mesoproterozoic Lower–Upper Ma'anshan and Puyu formations were sourced from the middle Trans‐North China Orogen (TNCO), while the Neoproterozoic Luotuopan and Hejiazhai formations were derived from the southern TNCO and the North Qinling Terrane, respectively. The clastic rock series in the southern NCC is divided into Luotuopan type and Hejiazhai type by detrital zircon U–Pb age pattern and Hf isotopic characteristics, suggesting Late Mesoarchean to Early Palaeoproterozoic (2.47–2.97 Ga) crustal growth in the interior NCC, and Late Palaeoproterozoic to Early Neoproterozoic (0.98–2.08 Ga) crustal growth in the marginal NCC. The crustal evolution of the NCC can be classified into three stages, namely >3.0 Ga continental nuclei generation, the Meso‐Neoarchean massive growth, and the Palaeo‐Mesoproterozoic interior reworking and marginal growth.