Identification of Permeability Level by using Fault Fracture Density Analysis and Landsat 8 OLI at Ulubelu Geothermal Area

Ulubelu geothermal field is located approximately 125 km at the west of Bandar Lampung, Lampung Province. Currently, the Ulubelu geothermal prospect has been developed as a geothermal power plant with 220 MW installed capacity. Ulubelu geothermal field began to operate since 2012 with the first capacity of 3x55 MW which has a temperature of 265°C with 1,160 kg/kJ average enthalpy and developed as water dominated system with single flash system technology. This research analyzes fault fracture density in the area to study the area which can potentially have high permeability or fracture by using remote sensing data (digital elevation map) to delineate the lineaments which can be observed at Ulubelu and surrounding. This research is also used Landsat 8 OLI data to determine the vegetation level of the Ulubelu area. The result of the analysis shows that there are three potential areas to be the recharge area, west of Mt. Pematang Sulah, west of Mt. Rendingan, and north of Mt. Rendingan. The recharge area should be preserved to maintain the geothermal system in the Ulubelu area.