Identification of geothermal pathways by fault fracture density (ffd) and gravity methods in Karangan sub-district, East Kutai district, East Kalimantan province

Abstract

Abstract The Presence of geothermal manifestations in the form of hot springs is very close to the presence of geological structures that become permeable zones in a Mangkalihat High geothermal system. There are two hot springs in this area, which are crossed by regional structures. So, it is important to identify the geothermal manifestation with the geological structure in this area to know the path of the geothermal flow. In this research, the fault fracture density method is used to determine the existence of structures on surface and the gravity method to determine the existence of structures below surface, which then from the results of the analysis will be correlated with the existence of geothermal manifestations in the area. The analysis results are found with the FFD method. The density of the study area has a value of 0 - 2,355 km/km2. Meanwhile, the results of the gravity method show that there are six normal faults and four thrust faults identified in the study area. Geothermal manifestations in the study area are related to the existence of high-density values in the study area, and geological structures identified through gravity are structures that are the pathway for the movement of hot springs.