Geochemical characteristics of lithium in surface waters of the Kulon Progo volcanic region for sustainable energy applications

Abstract The increasing global demand for lithium and other critical elements has intensified the need for efficient and cost-effective exploration approaches. This study presents a preliminary hydrogeochemical assessment of lithium distribution in the Kulon Progo volcanic region, Southern Mountains of Java, Indonesia, using integrated ICP-OES, X-ray diffraction (XRD), and petrographic analyses. Surface water samples contain lithium concentrations ranging from 0.01 to 0.49 ppm, with the highest value recorded in Banyuasin well water. Associated trace elements, including strontium, boron, barium, magnesium, and cobalt, were also detected, reflecting complex water–rock geochemical interactions within the volcanic system. Volcanic rock samples contain 5–57 ppm Li, reflecting substantial spatial variability related to lithological differences across the study area. XRD and petrographic analyses provide mineralogical context for interpreting lithium distribution; however, specific lithium-hosting mineral phases could not be conclusively identified. The integrated geochemical and mineralogical data suggest that water–rock interaction is a key process controlling lithium mobilisation and distribution. This study provides the first baseline dataset on lithium distribution in the Kulon Progo volcanic region, identifies previously unrecognised lithium anomalies, and demonstrates the value of integrated hydrogeochemical approaches for preliminary lithium exploration in Indonesian volcanic terrain.