Identification of Potential Prospect Areas Based on Gravity Data Analysis for Danau Ranau Geothermal Working Area

Abstract

Danau Ranau Geothermal Working Area (WKP) is geographically located in the southwestern part of the island of Sumatra, precisely in the border area between South Sumatra Province and Lampung Province. This area is influenced by the Great Sumatra Fault and is the intersection of the Komering Segment to the north and the Semangko Segment to the south. The Lake Ranau Geothermal Field is one of the WKP that is still in the exploration phase and there are no drilling wells or temperature gradient well. The main purpose of exploration is to determine the drilling location. The criterion for the success of the drilling target is an area that has high temperature and permeability. Temperature is associated with the existence of a heat source, while permeability is related to the existence of geological structures, both faults and sturdy structures filled with fluids that can be a media for heat energy transfer and are the target of this study. To obtain this information, this study was conducted using gravity data analysis with First Horizontal Derivative (FHD), and Euler Deconvolution analysis, to determine the structure below the surface to identify permeable zones, in order to help in the construction of geothermal system and the delineation of area prospects.