The hydrochemical evolution and genesis of geothermal waters in the Cuona-Woka Rift Zone of Southern Tibet were investigated to understand the geothermal system's nature and its relationship with geological, geochemical, and hydrological factors. Water samples from geothermal wells, springs, and surface waters in the region were analyzed for their chemical compositions, stable isotopes, and thermodynamic parameters. The results reveal that the geothermal waters in the Cuona-Woka Rift Zone are characterized by high concentrations of Na+, K+, SO4^2-, and Cl-, with moderate to high temperatures ranging from 60°C to 95°C. Geochemical modeling indicates that the geothermal waters are predominantly influenced by water-rock interaction processes, with the dissolution of silicate and carbonate minerals playing a major role. Isotopic analysis suggests a mixed origin of the geothermal waters, with contributions from both deep circulation and shallow recharge sources. This study provides a detailed understanding of the hydrochemical evolution of geothermal systems in the region and contributes to the broader understanding of geothermal energy resources in Tibet.

Geothermal waters, hydrochemistry, Cuona-Woka Rift Zone, Southern Tibet, geothermal systems, water-rock interaction, isotopic analysis

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