Resistivity Model Based on 2D Inversion of Magnetotelluric Sounding in Bacon-Manito, Philippines

Abstract

Two-dimensional (2D) inverse modeling of Magnetotellurics (MT) data gathered during several field campaigns in Bacon-Manito (Bac-Man) revealed three anomalies referred to as Palayan Bayan, Tikolob and Malobago. The combined interpretation of Schlumberger resistivity traversing (SRT) and vertical electrical sounding (VES) data, gravity data, geologic data, well alteration and stable temperature data has led us to conclude that each anomaly is associated with a geothermal system. The emergence of the E-W resistivity trend was noted to be aligned with the local gravity high and the good correlation of this resistivity trend with the major fault system in Bac-Man was also noted. The Palayan Bayan anomaly is associated with the current Palayan Bayan production field. The Tikolob anomaly is interpreted to be a possible geothermal system in the western sector of the Bacon-Manito field separate from Palayan Bayan system. The geothermal system associated with Malobago anomaly is believed to be relict due to the exposed conductive zone in the area as observed in the MT model and relict alteration minerals present on the surface. An elongated, less prominent anomaly branching from both Tikolob and Palayan Bayan may represent the shared outflow between the Tikolob and Palayan Bayan systems.