Geochemical constraints on the petrogenesis of the Neoproterozoic and Late Jurassic granitoids from the Jiudian gold deposit, Jiaodong Peninsula, North China Craton

• First detailed study of the Neoproterozoic and Jurassic granites in the Jiudian deposit is present. • Occurrence of Neoproterozoic granites confirms the Neoproterozoic magmatic event in the NCC. • High magmatic f O 2 facilitated the transport and enrichment of gold from the lower to upper crust. The Jiaodong Peninsula, located in the eastern North China Craton (NCC), constitutes the province with the third-highest gold output worldwide. Previous studies show that granitoids from this region were mainly emplaced in the Archean and Mesozoic whereas granites of other ages are scarce. These constraints pose challenges to elucidating the magmatic evolution and metallogenic processes that occurred throughout the formation and destruction of the NCC. To address these problems, the granites of the Jiudian gold deposit in the northern Jiaodong Peninsula were, for the first time, systematically examined using whole-rock major and trace element geochemistry combined with in situ zircon trace element analyses. The Jiudian granitoids, including biotite monzogranite and granitic gneiss, are metaluminous to weakly peraluminous, belonging to the high-K calc-alkaline series and exhibiting enrichment in large-ion lithophile elements and high-field strength elements with weak negative Eu anomalies. Nonetheless, zircon trace element analyses show that granites of distinct ages are characterized by notable disparities in oxygen fugacity, with the Neoproterozoic granite displaying higher oxidation state (ΔFMQ = 1.82 to 4.56) than the Late Jurassic granites and the zircon xenocrysts of Mesoarchean to Paleoproterozoic ages. The present work additionally shows that the Jurassic granites from the Jiudian deposit share broadly similar oxidation conditions with other Linglong-type granites, which corresponds to the values reported for the Guojialing- and Weideshan-type granites from the Jiaodong Peninsula. Comparison of trace element compositions between Neoproterozoic zircons from the Jiudian granitic gneiss and inherited zircons within the Linglong-type granites reveals close geochemical similarities, implying that the inherited Neoproterozoic zircons in the Mesozoic granites likely originated from Neoproterozoic wall rocks within the NCC rather than from the Yangtze Craton. Our results provide direct evidence for the existence of Neoproterozoic magmatism in the eastern NCC and highlight its significance in understanding crustal evolution and the metallogenic framework of the Jiaodong gold province.