ENVIRONMENTAL GEOLOGY, cilt.56, sa.5, ss.913-920, 2009 (SCI-Expanded)
In this study, reservoir temperatures of BalÄaut +/- kesir geothermal waters in northwestern Turkey are estimated with various geochemical models. The geothermal fluids in the region are represented by Na-SO4, Na-HCO3 and Ca-HCO3 type waters with discharge temperatures up to 98A degrees C. It was determined that the solubility of silica in most of the waters is controlled by the chalcedony phase. Equilibrium states of the BalÄaut +/- kesir thermal waters studied by means of Na-K-Mg-Ca diagram, mineral saturation calculations and activity diagrams in the system composed of Na2O-CaO-K2O-Al2O3-SiO2-H2O phases approximate a reservoir temperature of about 120A degrees C. Most of the waters are found to be equilibrated with calcite, chalcedony +/- A quartz and muscovite at predicted temperature ranges, similar to those calculated from the chemical geothermometers.