Application of Hydrogeochemical Diagrams and Geothermometry to Characterize the Samtskhe-Javakheti Geothermal System, Georgia

Abstract

The Samtskhe–Javakheti region of southern Georgia hosts significant geothermal resources associated with volcanic and tectonic activity. This study applies a combined hydrogeochemical and geothermometric approach to characterize the chemical evolution and thermal regime of thermal waters in the area. Major cation and anion analyses were interpreted using Piper, Durov, diamond grid, Ludwig–Langelier, and Schoeller diagrams to classify water types, evaluate mixing processes, and assess fluid–rock interactions. Reservoir temperatures were estimated using silica geothermometers and the Giggenbach Na–K–Mg triangle, distinguishing between immature and fully equilibrated fluids. Results indicate that thermal waters range from calcium–sulfate and mixed alkaline–bicarbonate types to sodium–potassium–chloride and alkaline–chloride–sulfate types, reflecting diverse geochemical evolution. Temperatures derived from silica geothermometers and the Giggenbach triangle range from 70 to 122 °C, consistent with medium-enthalpy geothermal reservoirs. The study demonstrates that Samtskhe–Javakheti thermal waters comprise a heterogeneous mixture of immature and equilibrated fluids, providing a comprehensive understanding of water evolution and thermal characteristics. These findings support future geothermal exploration and sustainable utilization of the region’s resources.