Work

Geochronology constrains Early Cretaceous gold mineralization in the Baiyun gold deposit, Liaodong Peninsula

Year: 2026

Type: article

Abstract: The Baiyun gold deposit in the Liaodong Peninsula, North China Craton, contains > 120t of gold, but its mineralization age and genesis remain contentious. To constrain the timing of gold mineralization, we conducted in-situ LA-ICP-MS U-Pb dating of monazite and rutile from auriferous ores, together with zircon grains from mineralized dikes. U-Pb analysis of monazite yields a concordia age of 1806.0 ± 38 Ma, which we interpret as Paleoproterozoic regional metamorphism instead of hydrothermal mineralization. Rutile yields two age populations at 1083.0 ± 37 Ma and 389.0 ± 30 Ma, attributed to Mesoproterozoic and Paleozoic tectono-thermal events, respectively. Zircon yields crystallization ages of 232.0 ± 2.0 Ma for diorite porphyrite dike, 225.9 ± 1.2 Ma for granodiorite dike, and 121.68 ± 0.48 Ma for granite dike. Field and petrographic evidence indicate that all dated dikes predate gold mineralization. Therefore, the youngest magmatic zircon age provides a maximum age for mineralization. Within the established regional geochronological framework, the data suggest that gold mineralization at Baiyun most plausibly occurred during the Early Cretaceous (ca. 120 Ma). To further elucidate its origin, we compare the mineralization age, geodynamics, ore-forming fluid characteristics, and the sources of gold-related metals and sulfur with those of well-characterized Jiaodong-type gold deposits. This comparison supports that Baiyun represents an Early Cretaceous Jiaodong-type mineral system, formed during lithospheric thinning driven by rollback of the paleo-Pacific plate.

Source: Ore Geology Reviews

DOI: 10.1016/j.oregeorev.2026.107172