21.15109/CONCORDA/XRLKLYHatvani, István GáborIstván GáborHatvani0000-0002-9262-7315HUN-REN Research Centre for Astronomy and Earth SciencesKern, ZoltánZoltánKern0000-0003-4900-2587HUN-REN Research Centre for Astronomy and Earth SciencesCzuppon, GyörgyGyörgyCzupponHUN-REN Research Centre for Astronomy and Earth SciencesReitmeyer, BenceBenceReitmeyerHUN-REN Research Centre for Astronomy and Earth SciencesARP2025Earth and Environmental Scienceswater stable isotopeshallow groundwaterhydrogeologygeochemistryHatvani, István GáborIstván GáborHatvaniResearch Centre for Astronomy and Earth SciencesHatvani, István GáborIstván GáborHatvaniHUN-REN Research Centre for Astronomy and Earth SciencesKern, ZoltánZoltánKernHatvani, István GáborIstván GáborHatvani2023-11-072025-03-042025-03-05numerical816181application/vnd.openxmlformats-officedocument.spreadsheetml.sheet1.0CC BY-NC-ND 4.0The dataset is the foundation of the first isoscape of Hungary from stable isotope samples collected from subsurface waters. The resulting series of maps not only carries new interesting information for society about the stable isotopic composition of underground waters but can also serve as a reference for further research, such as determining the mixing of underground waters, the spread of pollutants, etc. because waters of different origins have unique stable isotopic compositions, which serve as their fingerprint properties. The current version (v1) holds data for 2023 and 2024, it will be updated with sites and time points continuously.oxygen isotope composition (δ18O) of subsurface water in per mil (‰) relative to V-SMOW (Vienna Standard Mean Ocean Water) hydrogen isotope composition (δ2H) of subsurface water in per mil (‰) relative to V-SMOW (Vienna Standard Mean Ocean Water)Stable hydrogen and oxygen isotope composition of the samples were measured using a Liquid Water Isotope Analyzer (LWIA-24d) manufactured by Los Gatos Research Ltd. All samples were measured at least two times. The isotopic compositions of the water samples are expressed as δD and δ18O in ‰ relative to V-SMOW (Vienna Standard Mean Ocean Water (Coplen, 1996). The precision is better than 1.0‰ and 0.15‰ for δ2H and δ18O, respectively.Budapest, HUN-REN RCAES16.2047627221.780246148.5632163946.02539838