Separation of groundwater-flow components in a karstified aquifer using environmental tracers

In an attempt to identify the hydraulic connections among the various outlet points in the Travertine Plateau, southern Turkey, groundwater was analyzed for stable and radioactive isotopes, CFCs and helium. The upgradient springs, belonging to the Kirkgozler system were proved to be a mixture of recent and older water on the basis of their low C-14 values and their measurable tritium and CFCs. Downgradient springs discharging along the Mediterranean coast contain contributions from the Kirkgozler system, but a larger proportion of the recent water component that could be contributed from direct precipitation on the travertine, and recharge from watersheds to the east and west of the Travertine Plateau. This larger portion is evidenced by the water's increased tritium content, enriched oxygen-18 and deuterium values (suggesting a lower recharge altitude), a decreased C-14 content, atmospheric helium and CFCs contamination.