Multi-method dating constraints of the Wolonggang copper deposit in eastern Jidong and their implications for regional metallogenesis.

【Objective】The Qinglong Wulonggang pluton in eastern Hebei, North China, represents a Mesozoic magmatic–mineralization concentration zone within the Yanshanian orogenic belt. Addressing the unresolved issues of the temporal coupling between magmatic–hydrothermal processes at different temperature windows and the unclear contribution of Early Cretaceous tectonic inversion to mineralization, this study aims to clarify the staged links among Mesozoic tectonics, magmatism, hydrothermal activity, and mineralization through multi-system geochronology.【Methods】Samples of the Wulonggang pluton and associated copper mineralization were collected for zircon U–Pb, muscovite⁴⁰Ar/³⁹Ar, and apatite U–Pb dating, constraining the evolution of high-temperature magmatic emplacement, medium-temperature hydrothermal activity, and low-temperature thermal events, respectively.【Results】ZirconU–Pb dating indicates that the pluton formed during the Middle–Late Jurassic(171–159Ma), corresponding to a crustal thickening stage induced by subduction of the Paleo-Pacific plate, representing a pre-mineralization material accumulation period. Muscovite ⁴⁰Ar/³⁹Ar ages (159Ma) record medium-temperature hydrothermal activity associated with magmatic emplacement. Apatite U–Pb dating identifies two Early Cretaceous thermal events (136Ma and 112Ma): the former corresponds to the initial stage of regional tectonic inversion from compression to extension, revealing a “fluid-first” feature of the deep system under decompression; the latter coincides with the regional mineralization peak and the craton destruction peak, reflecting thermal resetting and reactivation of the mineralizing system.【Conclusion】The Wulonggang deposit experienced three evolutionary stages: a Middle–Late Jurassic magmatic emplacement and material accumulation stage, an Early Cretaceous initial thermal–fluid activation stage driven by tectonic inversion, and an Early Cretaceous late-stage thermal superposition and mineralization stage. Different geochronological systems reflect geological processes at distinct temperature windows, providing critical temporal constraints for reconstructing the regional metallogenic framework and identifying concealed mineralization systems.