Radiocarbon concentration and origin of thermal karst waters in the region of the Bukk Mountains, northeastern Hungary

Abstract

Found the water in warm springs and boreholes to be mixtures of cold young and old thermal water. Also determined short mean-residence times for some large cold springs. The 14C activities measured in these springs indicate that the recharge area of the karst aquifer is open to the atmosphere, and atmospheric CO2 contributes to the 14C activity of these groundwaters. Observed good correlation between 14C and 3H activities and determined negative correlations between 14C concentration and δ18O values of the oldest thermal waters, the authors attribute their origin to precipitation during colder temperatures than at present.