Identifikasi Sistem Panas Bumi Berdasarkan Analisis Medan Magnetik Total Di Daerah Gunung Kapur, Kabupaten Kerinci, Sumatera Barat

Anastasia Sherliana Yuli Christianti, Drs. Imam Suyanto, M.Si ; Tony Rahadinata, S.Si., M.T.

2026 | Skripsi | GEOFISIKA

Gunung Kapur, Kabupaten Kerinci, Sumatera Barat merupakan daerah yang berpotensi panas bumi akibat aktivitas vulkanik dan struktur geologi bawah permukaan. Penelitian ini bertujuan mengidentifikasi karakteristik anomali magnetik dan struktur geologi menggunakan metode magnetik. Data 300 titik pengukuran diolah melalui Reduction to Pole (RTP), pemisahan anomali regional-lokal, analisis spektrum, Total Horizontal Derivative (THD), Tilt Derivative (TDR), dan pemodelan 2,5D. Anomali regional berkisar -315,5 hingga 244,2 nT, dengan zona tinggi pada kisaran Easting 750.640–756.360 dan Northing 9.793.960–9.805.600, sedangkan zona rendah berada pada Easting 744.260–754.380 dan Northing 9.804.740–9.809.800. Anomali lokal berkisar -254,2 hingga 326,8 nT dan menunjukkan pola lebih kompleks akibat pengaruh sumber dangkal. Analisis THD dan TDR menunjukkan beberapa dugaan sesar atau kelurusan. Pemodelan 2,5D menunjukkan sembilan dugaan sesar pada sayatan B–B? dengan Easting 748.030–752.309, Northing 9.801.634–9.806.470, dan kedalaman ±0,25–1,10 km. Pada sayatan D–D? terdapat delapan dugaan sesar dengan Easting 752.210–756.534, Northing 9.799.490–9.804.570, dan kedalaman ±0,40–0,80 km. Model menunjukkan keberadaan granit, lava, batuan gunungapi tidak terpisahkan, Formasi Barisan, dan endapan danau. Sumber panas dan reservoir belum dapat ditentukan

Gunung Kapur, Kerinci Regency, West Sumatra, is a geothermal potential area influenced by volcanic activity and subsurface geological structures. This study aims to identify magnetic anomaly characteristics and subsurface geological structures using the magnetic method. A total of 300 magnetic measurement points were processed using Reduction to the Pole (RTP), regional–local anomaly separation, spectral analysis, Total Horizontal Derivative (THD), Tilt Derivative (TDR), and 2.5D modeling. The regional magnetic anomaly ranges from -315.5 to 244.2 nT. High-anomaly zones, ranging from 5.2 to 244.2 nT, occur at Easting 750,640–756,360 and Northing 9,793,960–9,805,600, while low-anomaly zones, ranging from -315.5 to -85.3 nT, occur at Easting 744,260–754,380 and Northing 9,804,740–9,809,800. The local anomaly ranges from -254.2 to 326.8 nT and shows a more complex pattern due to shallow sources. THD and TDR analyses indicate several suspected faults or lineaments. The 2.5D model identifies nine suspected faults along section B–B? at Easting 748,030–752,309, Northing 9,801,634–9,806,470, with depths of approximately ±0.25–1.10 km. Section D–D? contains eight suspected faults at Easting 752,210–756,534, Northing 9,799,490–9,804,570, with depths of approximately ±0.40–0.80 km. The model indicates granite, lava, undifferentiated volcanic rocks, Barisan Formation, and lake sediments. The undifferentiated volcanic rocks may be considered as a cap rock. The heat source and reservoir cannot be determined.

Kata Kunci : sistem panas bumi, sesar, metode magnetik, Gunung Kapur , geothermal system, fault, magnetic method, Gunung Kapur