Resistivity Models of Pantar Island Geothermal System East Nusa Tenggara, Indonesia

Yoqi Ali Taufan (Department of Geological Enginerring, Padjadjaran University, Bandung, Indonesia.)
I. Syafri (Department of Geological Enginerring, Padjadjaran University, Bandung, Indonesia.)
D. Risdianto (Department Centre for Minerals, Coal, and Geothermal Resources, Geothermal Group, Bandung, Indonesia.)
A. Zarkasyi (Department Centre for Minerals, Coal, and Geothermal Resources, Geothermal Group, Bandung, Indonesia.)
T. Rahadinata (Department Centre for Minerals, Coal, and Geothermal Resources, Geothermal Group, Bandung, Indonesia.)
W. Awaludin (Department Centre for Minerals, Coal, and Geothermal Resources, Geothermal Group, Bandung, Indonesia.)

Journal of Geoscience, Engineering, Environment, and Technology
Vol. 5 No. 3 (2020): JGEET Vol 05 No 03 : September (2020)

The subsurface geological conditions of a geothermal system are vital objects to be considered in geothermal exploration. The Magnetotellurics survey was conducted to explore for geothermal potential in Pantar Island. This is to achieve deeper penetration compared to our previous study that adopted resistivity method to determine reservoir zones based on rock resistivity models. The difference in rock resistivity in geothermal systems provides subsurface geological information in the form of low resistivity that associated the clay cap zones (high conductive), the medium resistivity zones associated with the reservoir zones, and high resistivity associated with a heat source. The results of 2D and 3D models from MT data show that the low resistivity value (<20Ωm) as a clay cover zones, this layer from the surface to -1000 meters. Medium resistivity values ​​(20-100 Ωm) starting from depths -1000 meters to -2000 meters associated with reservoirs zones, high resistivity values (> 200 Ωm) starting from depths of -2000 meters are considered as heat source from the Pantar geothermal system.