Zircon U–Pb Geochronology and Trace Element Geochemistry of Granitoids From the Guangning Gold District, Western Guangdong, China: Insights Into Multi‐Stage Gold Mineralization

Abstract

ABSTRACT The Guangning district in western Guangdong Province hosts structurally controlled gold deposits associated with long‐lived granitic magmatism from the early Palaeozoic to the late Mesozoic. However, the metallogenic significance of these magmatic episodes remains debated. This study integrates zircon U–Pb geochronology, morphological analysis, trace element geochemistry and Ti‐in‐zircon thermometry for early Palaeozoic granodiorite, early Mesozoic monzogranite and late Mesozoic biotite granite to constrain the temporal evolution of magmatism and its relationship to gold mineralization. Zircon U–Pb dating identifies three distinct magmatic–hydrothermal episodes at ~453–448 Ma (early Palaeozoic), ~249–247 Ma (Triassic) and ~93 Ma (Cretaceous). Early Palaeozoic zircons are dominantly euhedral and oscillatory zoned, consistent with typical magmatic crystallization and suggesting an important role in crustal preconditioning and possible metal pre‐enrichment. Triassic zircons commonly show rounded to resorbed morphologies, dark cathodoluminescence, low Th/U ratios (< 0.16) and strong Eu depletion (0.0001–0.19), indicating highly evolved magmas and intense late magmatic fluid interaction. Combined with published petrogeochemical, structural and isotopic constraints, these features identify the Triassic magmatic event as the principal stage of gold mineralization in the Guangning district. Cretaceous zircons (avg. ΣREE = 820 ppm, Ce/Ce* = 39.68, Eu/Eu* = 0.16) record a younger, comparatively oxidized magmatic episode that caused thermal‐fluid overprinting, remobilization and local upgrading of pre‐existing mineralization. These results suggest that gold mineralization in the Guangning district was not the product of a single magmatic event, but was controlled by multi‐stage magmatic–hydrothermal processes, with the Triassic event representing the dominant metallogenic episode. This study demonstrates the effectiveness of multi‐parameter zircon analysis in resolving complex, multi‐stage granitoid‐related gold mineralization processes.