2D magnetotelluric inversion and 3D resistivity visualization for geothermal system characterization: A case study of Mount Parakasak

Mount Parakasak in Banten hosts promising yet underexplored geothermal resources. This study integrates two-dimensional magnetotelluric (MT) and time-domain electromagnetic (TDEM) surveys to delineate subsurface resistivity structures and characterize the geothermal system. Thirty-six MT soundings, corrected for static shift using TDEM data, were inverted to generate 2D resistivity sections. These sections were subsequently interpolated to construct a three-dimensional resistivity visualization constrained by geological and geochemical datasets. The results identify a conductive clay cap (∼100 Ω·m) overlying an upflow zone near the Kaipohan manifestation, corresponding to estimated reservoir temperatures of 240–260 °C. The Batukuwung hot spring defines an outflow zone with temperatures of 52–75 °C. The integrated interpretation indicates an active geothermal system and identifies promising drilling targets at approximately 1500 m depth. These findings provide a robust framework for geothermal exploration and resource assessment, supporting future geothermal development in Banten Province.