GEOCHEMICAL AND HIDROGEOLOGY STUDIES OF GEDEPANGRANGO AND PANCAR GEOTHERMAL FLUIDS

• Main Author: CHRISTIN NATALIA , HAPPY
• Format: Theses
• Language: Indonesia
• Subjects: Geologi, hidrologi & meteorologi
• Online Access: https://digilib.itb.ac.id/gdl/view/72667
• Institution: Institut Teknologi Bandung

<p align="justify">The research area has three geothermal systems, i.e. geothermal system of Gunung Gede, Cikundul, and Gunung Pancar. These three systems are associated with magma from Gunung Gede, West Java. The purpose of this research is to determine the conceptual model of Gunung Gede and Gunug Pancar geothermal systems including its recharge area. The data used in this study are isotope 18O, 2H, and T, obtained from cold springs and river waters, and secondary data. Gunung Gede geothermal system is a water dominated system and has manifestation of fumarole, solfatara, Cl-SO4 and Cl-HCO3 fluids. Reservoir rock is at elevations of -500 to 250 m, temperatures of 270-295oC and has a concentration of 3144 mg/kg Cl. The clay cap is at elevations of 250 to 1,000 m. Gunung Pancar geothermal system has two manifestations, i.e. Cl-SO4 and SO4 fluids. Reservoir rock is at elevation -1,750 to -1,000 m, temperatures of 180-200oC and contains Cl 4000 mg/kg Cl. The cap rock is at elevation of -1,000 until 0 m. Cikundul geothermal system has a hot water manifestation of SO4 fluid and reservoir temperature of around 130-140oC. The result of isotope analysis of 18O and 2H shows that the recharge area of Gunung Gede geothermal system is at elevation 2,400-2,500 m, latitude of 9,253,000-9,254,000 mS, located in high FFD zone (30-60 km/100km2), and volcanic rock. While the recharge area of Gunung Pancar geothermal system is at elevation 800-900 m, latitude 9,265,000-9,266,000 mS, located in medium FFD zone (20-30 km/100km2), and sedimentary rock. The value of cold water tritium in the study area is 2.04-3.66 TU, <br /> <br /> indicating that the cold water in the research area is of submodern groundwater (infiltrated before 1952) and freshly permeated groundwater.<p align="justify">