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The Jinchanghe Pb-Zn polymetallic deposit is a representative distal skarn deposit in the Baoshan block. Due to limited research on the sources of ore-forming metals and trace elemental geochemistry of sulfides, the sources and mineralization environments of the Jinchanghe skarn Pb-Zn polymetallic deposit are still controversial. In this study, copper and sulfur isotopes and trace elements of sulfides from the Jinchanghe Pb-Zn polymetallic deposit were analyzed to reveal the sources of ore-forming materials and the ore-forming environments. The trace elemental analysis results show abundant Co, Ni, Mn and Se elements, and less As, Tl and Sb elements dominantly enter pyrite by isomorphic substitution, except for some Zn and Cu that occur as sulfide inclusions in Py1. Abundant Fe and Mn elements could substitute Zn to enter the sphalerite crystal lattice by the isomorphic substitution mechanism of (Fe2+ + Mn2+) ↔ 2Zn2+, and less Ag and Sb elements could enter the sphalerite by the isomorphic substitution mechanism of (Ag+ + Sb3+) ↔ 2Zn2+. The Cu-S isotopic and trace elemental compositions jointly suggest that the Jinchanghe distal skarn Pb-Zn polymetallic deposit formed from magmatic hydrothermal fluids with a sedimentary host-rock contribution, under mesothermal conditions (260 °C on sphalerite). [ABSTRACT FROM AUTHOR]

The Jinchanghe Fe-Cu-Pb-Zn polymetallic deposit is located in the northern Baoshan block in the Sanjiang metallogenic belt, southwestern China, and is one of the major large-scale Pb-Zn polymetallic deposits. This region is characterized by numerous diabase intrusions; however, research work is limited. This study elucidated systematic geochemistry and chronology of the diabase closely associated with orebodies in Jinchanghe to provide constraints for magma evolution. The results indicated that the Jinchanghe diabase was enriched in CaO, MgO, and Al2O3 and depleted in TiO2 and P2O5. Large ion lithophile elements were depleted, while for high field strength elements, the ratio of LREEs but depleted in HREEs. The zircon U-Pb dating results suggested that the diabase age could be divided into two stages, indicating the occurrence of two-stage tectonic-magmatic events in the Late Triassic and Early Cretaceous. The results also suggested that the metallogenic age of the Jinchanghe deposit is the Early Cretaceous. Moreover, the age was closely related to the collision after the closure of the mid-Tethys Ocean in the Early Cretaceous. Therefore, the results of this study provide new evidence for the tectonic-magmatic evolution and mineralization of the Baoshan block. [ABSTRACT FROM AUTHOR]