Characterization of Surface Geothermal Manifestation at Wayang Windu

Abstract

Geothermal energy is a critical natural resource for meeting global energy demands and supporting the transition to sustainable energy systems. This study investigates geothermal manifestations in the Wayang Windu area, including solfatar, fumaroles, and hot springs, to characterize their geochemical properties and assess exploitation potential. Geochemical analyses across three locations reveal variations indicative of an active geothermal system driven by hydrothermal fluid interactions with host rocks. Location LA-01 is characterized by dilute chloride-bicarbonate water with moderate pH, reflecting fluid mixing processes. Location LA-02 exhibits highly acidic hot springs with elevated hydrogen sulfide concentrations, indicative of sulfur oxidation processes. Location LA-03 further supports evidence of an active geothermal system, characterized by low pH and reducing conditions. The findings highlight the critical role of metal leaching and sulfur compound formation in shaping geochemical fluid characteristics and mineral alteration, such as pyrite transformation into hematite. While the geothermal system is active, the mixing of hydrothermal fluids with shallow groundwater impacts the efficiency of geothermal energy transfer. This study provides valuable insights into the geothermal potential of the Wayang Windu area and underscores the necessity of further investigations, including isotopic analysis and reservoir modeling, to assess sustainable and commercial exploitation prospects.