Chemical and isotopic composition of CO2-rich magnesium–sodium–bicarbonate–sulphate-type mineral waters from volcanoclastic aquifer in Rogaška Slatina, Slovenia

Bottled natural mineral waters from an andesitic aquifer in Slovenia are enriched in magnesium (1.1 g/l), sulphate (2.2 g/l) and dissolved inorganic carbon (204 g/l). We analysed major ions, trace elements, tritium activity, 14C, δ18OH2O, δ2HH2O,δ13CDIC, gas composition and noble gases in six wells. In addition, 87Sr//86Sr, δ34SSO4 and δ11B were analysed here for the first time. Stable isotopes with δ18O = −11.97 to −10.30‰ and δ2H = −77.3 to −63.8 confirm meteoric origin. CO2 degassing is evident at three wells, causing the oxygen shift of about −1.3‰. Tritium activity was detectable only in the shallowest well, where the freshwater component was dated to the 1960s. δ13CDIC in five waters is −1.78 to + 1.33‰, typical of carbonate dissolution. Radiocarbon is low, 1.03–5.16 pMC. Chemical correction with bicarbonate concentration and δ13C correction methods gave best mean residence times, slightly longer than previously published. Sulphate has δ34S 26.6–28.9‰ and δ18O 8.9–11.1‰ due to dissolution of evaporites in carbonate rocks. Boron at concentrations of 1.2–6.1 mg/l has two origins: δ11B = 11.3–16.4‰ from hydrothermal alteration and δ11B = 26.6–31.7‰ from carbonate dissolution. Strontium at concentrations of 0.5–22.0 mg/l has 87Sr//86Sr, indicating three sources: 0.7106 for Miocene clastic rocks, 0.7082 for Triassic carbonates and 0.7070 for Lower Oligocene andesitic rocks. CO2 represents the majority of the dissolved (> 98.84 vol%) and separated gas (> 95.23 vol%). Methane is only found in two wells with a max. of 0.30 vol%. All waters show excess helium and 16–97% of mantle-derived helium. Since all show subsurface degassing, the paleo-infiltration temperature could not be calculated.

TRITIUM DETERMINATION FROM WINE SAMPLES USING LIQUID SCINTILLATION COUNTING

Tritium measurement from aqueous fraction of the wines of known vineyard can be a useful tool in reconstruction of the tritium activity in different areas and makes possible to date the time of the harvest of the grapes. The goal of this study was to develop a suitable method for purification of the aqueous phase from the wine samples, obtained from different type of wines, in order to determine tritium activity concentration using liquid scintillation counting. In this work the influence of the purification method applied to the aqueous samples resulted from wine distillation was assessed by deuterium and tritium measurements, content of organic carbon, pH and conductivity. The most reliable purification method used for wine aqueous fractions, according with the results obtained for pH, and total organic carbon content is chemical treatment followed by lyophilization.

Isoscape of amount-weighted annual mean precipitation tritium (³H) activity from 1976 to 2017 for the Adriatic–Pannonian region – AP³H_v1 database

Tritium (3H) as a constituent of the water molecule is an important natural tracer in hydrological sciences. The anthropogenic tritium introduced into the atmosphere unintentionally became an excellent tracer of processes on a time scale of up to 100 years. A prerequisite for tritium applications is to know the distribution of tritium activity in precipitation. Here we present a database of isoscapes derived from 41 stations for amount-weighted annual mean tritium activity in precipitation for the period 1976 to 2017 on spatially continuous interpolated 1 km×1 km grids for the Adriatic–Pannonian region (called the AP3H_v1 database), with a special focus on post-2010 years, which are not represented by existing global models. Five stations were used for out-of-sample evaluation of the model performance, independently confirming its capability of reproducing the spatiotemporal tritium variability in the region. The AP3H database is capable of providing reliable spatiotemporal input for hydrogeological application at any place within Slovenia, Hungary, and their surroundings. Results also show a decrease in the average spatial representativity of the stations regarding tritium activity in precipitation from ∼440 km in 1970s, when bomb tritium still prevailed in precipitation, to ∼235 km in the 2010s. The post-2010 isoscapes can serve as benchmarks for background tritium activity for the region, helping to determine potential future local increases in technogenic tritium from these backgrounds. The gridded tritium isoscape is available in NetCDF-4 at https://doi.org/10.1594/PANGAEA.896938 (Kern et al., 2019).

Isoscape of precipitation amount-weighted annual mean tritium (³H) activity from 1976 to 2017 for the Adriatic-Pannonian region

Tritium (3H) as a constituent of the water molecule is an important natural tracer in hydrological sciences. The anthropogenic tritium introduced into the atmosphere became unintentionally an excellent tracer of processes on the time scale of up to a 100 years. A prerequisite for tritium applications is to know the distribution of tritium activity in precipitation. Here we present the spatially continuous gridded database (isoscapes) for amount-weighted annual mean tritium activity in precipitation for the period 1976 to 2017 on 1 × 1 km grids for the Adriatic-Pannonian Region (using 39 stations), with a special focus on post-2010 years which are not represented by existing global models. Three stations were used to check the model performance independently confirming its capability to reproducing the spatiotemporal tritium variability in the region. This Regional model is capable of providing reliable spatiotemporal input data for hydrogeological application at any place within Slovenia, Hungary and its surroundings. Results also show a decrease in the average spatial representativity of the stations regarding tritium activity in precipitation from ~ 600 km in 1970s when bomb-tritium was still prevailing in precipitation, to ~ 300 km in the 2010s. The post-2010 isoscapes can serve as benchmarks for background tritium activity for the region, helping to determine local increases of technogenic tritium from these backgrounds. The gridded tritium isoscape is available in NetCDF-4 at doi:10.1594/PANGAEA.896938 (Kern et al., 2019).