Integrated Remote Sensing as a Tool in Determining Areas with High Geothermal Potential in the Amacan Geothermal Prospect, Philippines

Abstract

Leonard is one of the active volcanoes in the Philippines, located in eastern Mindanao Island. It is interpreted to host the Amacan geothermal system characterized by Quaternary volcanism and favorable structural setting. In order to gain preliminary information on the prospect, remote sensing on the morphology, thermal anomalies, and zones of hydrothermal alteration were performed. Digital elevation models were processed to produce slope rasters which highlighted the geological features and topography. Major segments of the Philippine Fault and secondary structures were delineated, as well as caldera and domal features representing the potential heat sources. The Thermal Infrared Sensor (TIRS) Band 10 of Landsat 8 was also processed to generate the land surface temperatures. Thermal high anomalies were found to correlate with the distribution of the known thermal manifestations. The Operational Land Imager (OLI) bands of Landsat 8 were also processed using composite and band ratio operations to display the alteration zones and determine the alteration type. Using the Analytical Hierarchy Process (AHP) and Weighted Overlay Analysis in GIS, the remote sensing results were integrated to produce a geothermal potential map. Four areas were identified to have high geothermal potential and are recommended for more detailed assessments.