Sulfur and lead isotopic compositions and deep 3D geological model of the Wulong gold deposit in Liaoning Province

The Wulong gold deposit in Liaoning is a typical large-scale gold deposit within the Liao-Ji Rift, with complex mineralization processes. To further investigate its ore-forming material sources and deep-seated characteristics, studies on S and Pb isotopes, as well as gravity, magnetic, and electrical profiles, were conducted on the gold deposit. The δ³⁴S values of the gold ores range from 0.1‰ to 3.5‰ (averaging 1.66‰), whereas those of the Wulong pluton range from -21.4‰ to -8.4‰ (averaging -17.05‰). In terms of lead isotopes, the gold ores yield ²⁰⁶Pb/²⁰⁴Pb ratios of 17.569-17.672, ²⁰⁷Pb/²⁰⁴Pb ratios of 15.572-15.681, and ²⁰⁸Pb/²⁰⁴Pb ratios of 38.533-38.904. The Sanguliu pluton exhibits similar compositions, with ²⁰⁶Pb/²⁰⁴Pb ratios of 17.649-17.945, ²⁰⁷Pb/²⁰⁴Pb ratios of 15.552-15.616, and ²⁰⁸Pb/²⁰⁴Pb ratios of 38.521-38.934. In contrast, the Wulong pluton shows relatively lower radiogenic lead isotopic compositions, with ²⁰⁶Pb/²⁰⁴Pb ratios of 17.422-17.769, ²⁰⁷Pb/²⁰⁴Pb ratios of 15.591-15.634, and ²⁰⁸Pb/²⁰⁴Pb ratios of 38.323-38.845. Sulfur isotopic data indicate that the sulfur in the gold ores is of magmatic origin, whereas the sulfur isotopic composition of the Wulong pluton likely reflects the incorporation of crustal sulfur. Lead isotopic data reveal a similarity in lead isotopic compositions between the Sanguliu pluton and the gold ores, but a distinct difference between Wulong pluton and the gold ores. The Wulong gold deposit is classified as a magmatic-hydrothermal deposit and is closely associated with Early Cretaceous magmatism. Gravity, magnetic, and electrical profiles, combined with a 3D geological model, reveal a concealed Early Cretaceous pluton in deep on the northeast of Wulong gold deposit, indicating significant deep-seated prospecting potential.