The giant Shilu Fe-Cu-Co deposit in Hainan Island, South China, which was structurally and hydrothermally superimposed, is mainly hosted in highly metasomatized dolostones/marbles of the ~ 900 Ma Shilu Group. This study confirmed that the ore bodies are originally strata-bound and epigenetic, but do not have spatial relations with any coeval intrusions. In this study, the paragenetic sequence of the pre-deformation mineralization is refined and consists of early Ca-silicate alteration (I), Fe (II), and Cu-Co (III) mineralization stages, followed by multiple overprints and/or undeformed veins (stage IV). Our new oxygen and in situ Pb–S isotopic results for stages I to III show that the mineralizing fluids were initially magmatic-hydrothermal but have undergone variable degrees of interaction with country rocks during mineralization. On the other hand, stage IV fluids have in situ Pb–S isotopic compositions indicative of significant contributions of early-stage components through secondary re-mobilization. These features, in combination with chemical compositions of Fe oxides (e.g., elevated Ti in hematite), strongly argue that the Shilu deposit does not belong to BIF as previously considered, but is typical of magmatic-hydrothermal IOCG deposits. New sulfide Re-Os isotopic data show that the major Fe-Cu-Co mineralization formed at 780 ± 24 Ma (MSWD = 0.62). The deposit is confirmed to be broadly comparable to Neoproterozoic IOCG deposits in the Ailao Shan-Red River shear zone in terms of timing and nature of mineralization. Given that the shear zone likely extends to Hainan Island, the Shilu deposit is considered to be part of the same IOCG metallogenic belt and similar mineralization along the shear zone may be more widespread than previously thought.

华南海南岛石鹿铁铜钴矿床为构造和热液叠合，主要赋存于～900马石鹿群高度交代的白云岩/大理岩中。本研究证实，矿体原本为地层束缚和表观成因，但与任何同时代的侵入体均无空间关系。在这项研究中，预变形矿化的共生序列得到了细化，包括早期的钙硅酸盐蚀变（I）、铁（II）和铜钴（III）矿化阶段，随后是多次叠印和/或未变形静脉（第四阶段）。我们对阶段 I 至 III 的新氧和原位 Pb-S 同位素结果表明，成矿流体最初是岩浆热液，但在成矿过程中与围岩发生了不同程度的相互作用。另一方面，IV 期流体具有原位 Pb-S 同位素组成，这表明早期组分通过二次再迁移具有显着贡献。这些特征与 Fe 氧化物的化学成分（例如赤铁矿中的 Ti 含量升高）相结合，有力地证明了 Shilu 矿床不属于之前认为的 BIF，而是典型的岩浆-热液 IOCG 矿床。新的硫化物 Re-Os 同位素数据表明，主要的 Fe-Cu-Co 矿化形成于 780 ± 24 Ma (MSWD = 0.62)。该矿床被证实在成矿时间和性质方面与哀牢山-红河剪切带新元古代IOCG矿床大致相当。鉴于剪切带可能延伸至海南岛，