A LOW-COST UAV BASED APPLICATION FOR IDENTIFY AND MAPPING A GEOTHERMAL FEATURE IN IE JUE MANIFESTATION, SEULAWAH VOLCANO, INDONESIA

Mt. Seulawah Agam could make a good location for a geothermal power plant with an estimated energy of 150 Mwe. In geothermal exploration, thermal and multispectral imagery is required for surface temperature calculation, subsurface temperature modeling, and mapping of geothermal potential in volcanoes. In general, temperature data and vegetation index are obtained through such satellite images as Landsat, MODIS, and Sentinel. However, satellite images cannot be used for a small area due to the low resolution (> 15 m/px). In this study, the researchers used a small DJI Phantom 4 Quadcopter equipped with the FLIR One and MAPIR Survey 3 sensors to map the heat signatures of a geothermal feature from the Ie Jue geothermal manifestation, Seulawah Agam, Indonesia. An area of 500 m x 430 m has been scanned, and the images were mosaicked and processed using Drone Deploy Cloud and ArcGIS 10.2. Based on the data processing, NDVI data calculated from the MAPIR sensor are capable of showing vegetation contrast with high resolution (5 cm/px) in several manifestations, which also correspond to Landsat-8 imagery. Meanwhile, the FLIR thermal sensor shows a temperature of 85 °C in the manifestation area, which was confirmed by a geo-thermometer and field outcrops. It was proved that, compared to satellite imagery, UAVs could be applied effectively to support the quantitative assessment of geothermal resources in volcanoes.