CONCEPTUAL MODEL AND POTENTIAL OF KEMBAR VOLCANO GEOTHERMAL SYSTEM, ACEH BASED ON GEOCHEMICAL MANIFESTATION

• Main Author: Hendrik Sibarani, Andrian
• Format: Final Project
• Language: Indonesia
• Subjects: Geologi, hidrologi & meteorologi
• Online Access: https://digilib.itb.ac.id/gdl/view/75648
• Institution: Institut Teknologi Bandung

Kembar Volcano is a Quarternary stratovolcano inside the Kembar Caldera and associated with the Sumatera Fault system. There are two post-caldera eruption centers called Burni Kembar and Burni Waihlup and one eruption center on the caldera rim called Burni Kelalang. The volcanic complex of Kembar Volcano has a volume of about 75 km3 indicating the possibility of a large geothermal energy potential. Manifestations of geothermal occurring in this volcanic complex include fumarole, solfatara, kaipohan and hot springs. The main objective of study is to make a conceptual model and calculate the geothermal potential of the Kembar Volcano. The other objectives are to understand the lithology of reservoirs, the geological structures controlling the permeability pathways, hydrothermal fluids characteristics, flow pattern in the subsurface and geothermal potential of the Kembar Volcano. Methods used are literature studies, analysis of temperature anomalies from Landsat-8 satellite imagery, lineament analysis of DEM, water and gas geochemistry for anions, cations, and stable isotopes ?18O dan ?2H analyses. The results show that the Kembar Volcano is a high enthalpy volcanic geothermal system. The heat source of this system is the residual magmatism of the Late Pleistocene-aged Kembar Volcano. The reservoir of geothermal system lies at a depth of ±1500 m having lithology of Sandstone and Limestone Units and permeability type of faults and fractures. Geothermal fluid with a temperature of 260±10oC flows from the reservoir to the upflow zone around the Waihlup Crater, then flows to the outflow zone outside the Kembar Caldera through the Merpunge Fault and appears as a manifestation of warm to hot water along the Blangkejeren Fault (i.e., part of the Sumatera Fault). The Kembar Volcano has a high geothermal potential; its resources are 225 to 320 MWe.