Helifalcon® Airborne Gravity Gradiometry and Helitem® Airborne Electromagnetics for Geothermal Exploration, Musadake-Teshikaga, Japan.

Abstract

Summary An integrated interpretation of geological and geophysical data for Japan Oil, Gas and Metals National Corporation (JOGMEC) in the Musadake-Teshikaga area, Hokkaido, Japan. HeliFalcon® airborne gravity gradiometer (AGG) and Helitem® airborne electromagnetic (AEM) and magnetic data were acquired to facilitate the identification of prospective areas for geothermal energy generation. The interpretation workflow included: 1) Investigation of the regional geologic setting, using public domain data 2) Individual Interpretation of the acquired airborne datasets 3) Integration of the airborne geophysical data interpretations 4) Identification and prioritisation of the prospective geothermal zones Tectonic and volcanic features are mapped using the AGG, magnetic and AEM data. The AEM data was also used to identify low resistivity zones that potentially correspond with hydrothermal alteration zones. Low resistivity zones were mapped from the AEM data and appear to correlate with areas that have relatively low magnetic amplitudes. This suggests possible magnetite destruction and demagnetization related to thermal or hydrothermal activity. Low resistivity zones are more pronounced and common in the eastern Musadake area and therefore the geothermal exploration will be focused on this area.