Noble gas temperatures and ages of some glacial and buried brine waters in Poland

Noble gas measurements on six palaeowater systems in Poland were performed in order to confirm hypotheses on age and origin of these groundwaters. Thermal waters in Cieplice Spa, Sudenten, show mean noble gas temperatures of 2 deg. C, four degrees lower than recent temperatures; therefore these waters are related to glacial origin. In Ladek Spa, Sudeten, thermal waters with noble gas temperatures of 4.2 deg. C have been measured. They agreed with recent temperatures for a reasonable recharge altitude of 800 m, supporting early Holocene recharge, as expected from high 14C values. For an artesian aquifer in the Krakow region, noble gas temperatures of 2-3.5 deg. C were observed, distinctly below the present mean temperature of 7.5 deg. C, confirming the glacial age of water deduced from depleted δ18O and δD values. Amounts of radiogenic 4He and 40Ar of the investigated aquifers are in accordance with the derived ages, on the assumption of 4He and 40Ar crustal degassing fluxes as reported in the literature. Only for Cieplice Spa does a distinct deviation occur which cannot be explained on the basis of the available data. In Busko Spa the two different mineral waters with high total dissolved solids content yield noble gas temperatures of 4.8 deg. C and 24 deg. C, respectively. Ages related to excess 4He and 40Ar are higher than 50 ka for the shallow system. The deep waters are supposed to be of pre-Quaternary origin, supported by stable isotopes, 4He contents of 3.5 x 10-4 cm3·g-1(STP) and 40Ar/36Ar ratios of about 311. Noble gas data from brines in Debowiec and Goczalkowice Upper Silesia, are not interpretable owing to high methane contents resulting in strong degassing of the exploited waters. (author). 34 refs, 3 figs, 2 tabs