CHARACTERIZATION OF GROUNDWATER AND GEOTHERMAL MANIFESTATION IN THE MOUNT BONGKOK AREA, LEBAK REGENCY, BANTEN PROVINCE USING HYDROGEOCHEMICAL AND ISOTOPIC METHODS

• Main Author: Nur Setianingrum, Heny
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/73068
• Institution: Institut Teknologi Bandung

This research aims to characterize groundwater and geothermal manifestations in the Mount Bongkok area, Banten. The methods used include hydrogeochemical analysis and stable isotope analysis of groundwater. Water samples were collected in a 10 km2 study area, and physical and chemical parameters such as pH, salinity, and TDS were measured directly in the field. The water samples were then prepared for specific tests, including Ion Chromatography (IC), alkalinity titration, Inductively Coupled Plasma Mass Spectrometry (ICP-MS), and stable isotope analysis. The data obtained from the sample testing were processed and analyzed using the Piper Diagram, Ternary Diagram, and stable isotope ratio analysis methods. The results of the study showed that the water type in the research area was dominated by meteoric water, characterized by a dominant bicarbonate content. The Cikawah and Handeuleum hot springs exhibit characteristics of geothermal fluids rising to the surface. Based on isotopic and dissolved ion analysis, indications of mixing were found between meteoric water and geothermal fluids, either through H2S exchange or CO2 condensation. The findings of this research provide a better understanding of the characteristics and physicochemical composition of water in the hidden geothermal system around Mount Bongkok. The results can contribute to a deeper understanding of the genesis and mixing mechanisms of groundwater in the study area and serve as valuable information for the development of geothermal resources in Kabupaten Lebak and its surrounding areas.