A stable isotopy study of geothermal waters in Serbia

摘要

An investigation of the stable isotope compositions of thermal waters in central Serbia was initiated in 1986 to provide an isotope database for geothermal resource assessment purposes. Samples of water at 66 locations from various sources (thermal springs, dug wells, and boreholes) were collected for conventional isotope hydrological analysiss (D, ~(18)O, ~(13)C). Most of the examined waters are of the N_a-(Ca)-Mg-HCO_3(SO_4)-(Cl) type, with temperatures ranging from 16 to 111℃. The deuterium and ~(18)O compositions are in wide range from -42 to -106per thousand for δD and between -3.3 and -12.9per thousand for δ~(18)O. The isotopic data on δD and δ~(18)O for the thermal waters indicate their meteoric origin. An evaluation of the actual temperature in depth of the geothermal reservoirs was performed for the case of the oxygcn-18 shift appearance in discharged waters.