INTERPRETATION OF GRAVITY METHOD IN IDENTIFYING GEOTHERMAL POTENTIAL IN LIMBONG, LUWU UTARA DISTRICT, SOUTH SULAWESI

• Main Author: Adur
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/55361
• Institution: Institut Teknologi Bandung

The development of geothermal energy in Indonesia can help meet the needs of the Indonesian people for energy that continues to increase and replace fossil energy which will run out someday. Therefore, it is necessary to conduct geophysical exploration to meet geothermal activity and subsurface geological conditions where the gravity method is an effective method used in geothermal exploration. The area that is the object of research is the Limbong area, North Luwu Regency, South Sulawesi. The research aims to determine the model of the geothermal system that develops in the Limbong geothermal field. Based on gravity and topographical observation data from the Center for Coal and Geothermal Mineral Resources (PSDMBP) in 2010, this study uses these data to determine the value of the Complete Bouguer Anomaly (CBA) in the Limbong geothermal field. The results obtained from CBA data processing are in the form of a complete Bouguer anomaly map with an anomaly value range of -81 to -65 mGal using the density obtained from the average rock density, which is 2.62 gr / cm3. After that, the data was processed using two methods, namely themethod moving average and the second order polynomial. The results of the anomaly values of the two methods are compared and the one that is the most optimal for further data processing is selected. The Bouguer anomaly map shows the presence of low anomalies in the middle of the study area and high value anomalies in the eastern and western parts of the study area. The residual anomaly results in the second order polynomial method which shows high anomaly values in the northwest and south of the study area are estimated to be due to the presence of volcanic rock units that are still fresh and massive, so this method is considered superior to themethod moving average. There are 3 components of the Limbong geothermal system. First, diorite intrusion which is thought to be a source of heat, second inseparable volcanic rock is thought to be a reservoir, and the layer which is thought to be caprock is a rock layer of andesitic lava flow and pyroclastic lava flow-1