Identification of Fault Structures Using First Horizontal Derivative and Second Vertical Derivative Analysis of Gravity Data in the Sumedang Area, West Java

Laudrien Natarissa (Department of Geophysics, Faculty of Mathematics and Natural Science, Universitas Padjadjaran, Bandung, Indonesia)
Noor Muhammad Indragiri (Geological Agency, Ministry of Energy and Mineral Resources, Geological Survey Center)
Mochamad Ervan (Geological Agency, Ministry of Energy and Mineral Resources, Geological Survey Center)
Hesty Sampeliling (Geological Agency, Ministry of Energy and Mineral Resources, Geological Survey Center)
Budy Santoso (Department of Geophysics, Faculty of Mathematics and Natural Science, Universitas Padjadjaran, Bandung, Indonesia)

Eksakta : Berkala Ilmiah Bidang MIPA
Vol. 27 No. 04 (2026): Eksakta : Berkala Ilmiah Bidang MIPA (E-ISSN : 2549-7464) In Progress

Sumedang is a region with complex tectonic activity, making the identification of subsurface fault structures essential for understanding geological conditions and potential geohazards. This study aims to identify subsurface fault structures in Sumedang, West Java, using gravity data through First Horizontal Derivative (FHD) and Second Vertical Derivative (SVD) analysis. A total of 271 Bouguer anomaly data points were analyzed through regional–residual anomaly separation, spectral analysis, derivative analysis, and 2D forward modeling. Spectral analysis estimated average regional and residual depths of 9188.13 m and 2564.5 m, respectively. Fault interpretation was conducted based on the relationship between the SVD zero points and the extreme values of the FHD, supported by residual anomaly contrasts. The results indicate reverse faults, normal faults, and strike-slip faults with reverse components. The identified structures include the Baribis Fault on lines 5 and 7, the Rajamandala Fault on line 1, and the Cimanuk Fault on line 5, consistent with the Java–Bali–NTB active fault database. The 2D modeling results reveal the presence of younger sediment, older sediment, and basement. The study demonstrates that the combination of FHD and SVD analysis is effective for identifying subsurface fault structures in tectonically complex regions such as Sumedang.