| Title | Evaluating the Fluid Chemistry and Isotope Signature of Thermal Waters from Ladakh, India |
|---|---|
| Authors | Syed Hilal Farooq, Arindam Dey |
| Year | 2026 |
| Conference | World Geothermal Congress |
| Keywords | |
| Abstract | India is actively advancing in developing and utilizing clean energy, focusing on geothermal and solar resources. The union territory of Ladakh, part of the Trans-Himalayan geothermal province, holds significant geothermal potential, as evidenced by numerous active thermal springs. This study investigates the hydrochemical and isotopic signatures of thermal waters to understand their genesis, subsurface interactions, and geothermal viability. Eighteen thermal water samples were collected from three distinct geothermal clusters in Ladakh, along with eight surface water samples (avg. temp. 15°C) and four groundwater samples (avg. temp. 10°C) from nearby areas for comparative analysis. These were analyzed for major and trace elements, as well as stable isotopes of oxygen (δ¹⁸O) and hydrogen (δD). The thermal waters differ significantly in various physico-chemical parameters from surface and groundwater samples. The thermal springs fall under Na-Cl to Na-HCO₃ facies, indicating significant rock-water interaction and ion exchange with the deep-seated granitic intrusions. In contrast, surface and groundwater samples exhibit Ca-HCO₃ facies, typically indicating the shallow water circulation. Isotopic data (δ¹⁸O and δD) indicate a meteoric origin of the thermal waters with partial isotope shift due to evaporation or rock-water interaction. Chemical geothermometers applied in Puga thermal waters indicate the reservoir temperatures in the range of 200°C–230°C. The Chumathang thermal water reflects medium-enthalpy conditions (≈180±20°C), while Panamik represents a low to medium enthalpy regime (≈100±20°C). These findings highlight the diverse geothermal potential across Ladakh’s thermal provinces and provide a scientific basis for targeted geothermal exploration and sustainable energy development in the region. |