資源探査に関する研究の動向と大規模データプロセッシング

[3K0701-08-04] Detection of high potential area of geothermal resources by PS-InSAR technique

○Panggea Ghiyats Sabrian¹, Asep Saepuloh², Katsuaki Koike¹ (1. Kyoto University, 2. Bandung of Institute Technology)

Keywords:Sentinel-1, fault effect, heat source, geothermal exploration, Indonesia

Surface displacement is a common phenomenon in the field of geothermal and displacement analysis is often implemented to monitor the effects of steam production or injection. However, this technique has not been widely used in geothermal resource exploration. In a geothermal field, fault can be a fluid path and heat source evolution can affect displacement above its surface. These two phenomena can be detected using displacement analysis by the Interferometric Synthetic Aperture Radar (InSAR) technique applied to geothermal potential regions. Although the conventional Differential InSAR (D-InSAR) usually was used to obtain the surface deformation, this method is limited by two errors originating from atmospheric phase delay and inaccurate topographic phase components removal. These errors lead to decrease the detected accuracy of surface deformation. To overcome these problems, we applied the PS-InSAR method to determine the surface deformation accurately in an Indonesian geothermal field using Sentinel-1 data of ESA (European Satellite Agency) at ascending and descending modes from 2014 to 2017. The results revealed that the deformation occurred around the production wells, fluid paths, and estimated heat source region. A noteworthy feature detected is an effect of major faults on the large surface deformation.