Mineralogical Characteristics, Fluid Inclusions, C–O Isotope Geochemistry, and Rb–Sr Isotope Systematics of Listvenites Related to the Eastern Taurus Ophiolites, Malatya, Türkiye

This study integrates mineralogy, fluid-inclusion microthermometry, C–O isotope geochemistry, and Rb–Sr isotope systematics to constrain fluid–rock interaction in the Hekimhan and Kuluncak listvenites. The assemblages are dominated by dolomite, calcite, and quartz and commonly contain cerussite, tetrahedrite, galena, anglesite, pyrite, and chalcopyrite. Fluid inclusions homogenize at 285–417 °C and have salinities of 6.16–13.40 wt.% NaCl eq.; eutectic temperatures of −22.5 to −39.5 °C are consistent with fluids related to the H2O–NaCl–FeCl2 system. Carbonate δ13C VPDB values range from −4.54 to +4.31‰ and laboratory-reported δ18OVSMOW values from 22.15‰ to 31.95‰; calculated δ18OH2OVSMOW values range from +9.55‰ to +18.16‰, indicating heterogeneous fluid–rock interaction. Measured 87Sr/86Sr ratios range from 0.708696 to 0.711060 and 87Rb/86Sr from 0.011 to 3.534. The carbonate Rb–Sr regression yields 42 ± 17 Ma, with an initial 87Sr/86Sr ratio of 0.70871 ± 0.00046 and MSWD = 2.4. The 42 Ma central value falls within the Middle Eocene and is compatible with a Middle Eocene hydrothermal carbonation event, although the relatively large uncertainty and four-sample dataset warrant cautious interpretation. Trace-element enrichments in As–Cu–Ni–Pb–Sb, Pb–Cd, and Cu–Sr–Ba indicate localized metal redistribution. The integrated dataset supports structurally focused, multistage carbonation–silicification followed by metal-bearing hydrothermal overprinting under evolving physicochemical conditions.