This dataset contains stable and clumped isotope data obtained from pedogenic carbonates sampled across a continental sedimentary section at Büyükteflek (Anatolia, Turkey). The section spans the Priabonian and lower Rupelian stages (~37–33 Ma), including the Eocene–Oligocene Transition (EOT) and the Early Oligocene Glacial Maximum (~33.65 Ma). δ¹⁸O water estimates provides reconstructed δ¹⁸O values of meteoric water derived from clumped isotope paleotemperatures and carbonate δ¹⁸O values.

Stable isotope analyses (δ¹³C, δ¹⁸O) were performed on 23 calcite-dominated pedogenic carbonate powders using a Thermo 253+ mass spectrometer coupled to a Thermo Kiel IV device (Dual Inlet mode) at CEREGE (Aix-Marseille University). Sample powders (80–120 µg) reacted with 105% phosphoric acid at 70°C. Values are reported relative to IAEA-603 in the V-PDB reference frame. Full analytical details are provided in Supplementary Text S1 of Botté et al. (preprint).