Dalam eksplorasi geotermal, metode magnetotellurik (MT) berperan penting dalam memberikan informasi distribusi resistivitas bawah permukaan. Melalui pemodelan resistivitas, dapat mengidentifikasi lokasi komponen sistem geotermal yang umumnya ditandai oleh keberadaan lapisan anomali konduktif sebagai caprock. Batas bawah caprock mengindikasikan keberadaan top of reservoir (ToR) pada sistem geotermal. Agar hasil pemodelan akurat, desain survei yang optimal perlu dirancang, termasuk penentuan jarak antar stasiun. Jarak yang terlalu rapat meningkatkan biaya dan waktu, sementara jarak terlalu renggang akan berpotensi menurunkan resolusi. Oleh karena itu, studi ini bertujuan menentukan jarak antar stasiun optimum untuk eksplorasi geotermal melalui pemodelan forward dan inversi. Pemodelan forward dilakukan untuk mensimulasikan variasi jarak antar stasiun berdasarkan model bawah permukaan lapangan geotermal. Hasil pemodelan forward dilakukan inversi 1D, 2D, dan 3D untuk dibandingkan resolusinya. Hasil penelitian menunjukkan bahwa jarak 500 m merupakan jarak optimum di area interest untuk mendeteksi batas anomali konduktif, sehingga kedalaman ToR dapat ditentukan lebih akurat. Sementara itu, jarak 1 km masih cukup efektif di luar area interest. Pada hasil juga menunjukkan, inversi 3D memberikan resolusi lebih baik dalam menggambarkan geometri anomali konduktif dibandingkan inversi 1D dan 2D, serta tidak menunjukkan adanya struktur palsu.

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In geothermal exploration, the magnetotelluric (MT) method plays a crucial role in providing information on subsurface resistivity distribution. Through resistivity modeling, it is possible to identify the locations of geothermal system components, which are typically characterized by the presence of a conductive anomaly layer acting as a caprock. The lower boundary of the caprock indicates the top of the reservoir (ToR) in a geothermal system. To ensure accurate modeling results, an optimal survey design is essential, including the determination of station spacing. Spacing that is too close increases cost and survey time, while spacing that is too wide may reduce resolution. Therefore, this study aims to determine the optimum station spacing for geothermal exploration through forward modeling and inversion. Forward modeling is conducted to simulate variations in station spacing based on a geothermal field subsurface model. The results of forward modeling are then subjected to 1D, 2D, and 3D inversion to compare their resolution. The findings indicate that a 500 m station spacing is optimal within the area of interest for detecting the boundary of the conductive anomaly, allowing for more accurate determination of the ToR depth. Meanwhile, a 1 km spacing remains effective outside the area of interest. The results also demonstrate that 3D inversion provides better resolution in depicting the geometry of the conductive anomaly compared to 1D and 2D inversions, and does not produce false structures.