hydrogeochemistry and geothermometry

The Pamukkale Geothermal Field (PGF) of the Denizli Basin (SW Turkey) is one of the most distinguished active geothermal fields known in the World. The thermal waters from the PGF are subdivided into two groups (Group 1A: Ca-HCO3 and Group 1B: Ca-SO4 types). The cold waters are also classified into two groups (Group 2A: CaHCO3 and Group 2B: Mg-HCO3 types). The hydrogeochemical properties of the PGF thermal waters suggest interactions with the basal metamorphic rocks of the Menderes Massif, tectonically overriding by the carbonate rocks of the Lycian Nappes and sedimentary rocks of the Neogene formations. The bedrock units are stratigraphically overlain by the Neogene sedimentary units of the Denizli Group.The thermal springs of the PGF are affected by several hydrothermal processes including mixing, water-rock interaction and input of mantle volatiles. The thermal water plots of the PGF deviate from the full equilibrium line indicating a low water maturity and/or mixing processes. Mixing models and Na-K-Mg ternary diagram suggest mixing between meteoric and thermal waters during the uprising of the deep-originated fluids. The water-rock interaction leads saturation of calcite and induces travertine precipitation in the discharge area.Low tritium (