A Multi-Method Gravity Workflow for Reliable Structural Mapping in Northern Tunisia

High-resolution gravity data were used to assess their potential and limitations as a subsurface investigation tool to constrain key geological structures and support georesource exploration in Northwestern Tunisia. In this structurally complex area, methodological choices—particularly those related to regional–residual separation, derivative filtering, interpolation schemes, and Euler-based depth-estimation parameters—significantly influence the geometry, continuity, and uncertainty of interpreted lineaments.

To mitigate these effects, we applied an integrated multi-stage workflow combining residual anomaly mapping, derivative filters, tilt-angle transformation, power-spectrum analysis, Euler deconvolution of horizontal gradients (EHD), and 3D Euler solutions. These complementary approaches delineate subsurface fault systems and highlight deep structural controls on Triassic salt diapirs and associated Pb–Zn mineralization. The results reveal a dominant NE–SW structural corridor with fault depths reaching ~1.75 km, spatially correlating with known mineralized sites and salt-dome boundaries.

To further enhance structural reliability and quantify subsurface density distributions, the workflow incorporates 3D gravity inversion. The inversion model helps image density contrasts associated with the Triassic evaporites, validating interpreted lineaments and refining depth estimates derived from derivative-based and Euler approaches. Integrating forward–inverse modelling with classical interpretation tools not only enhances the structural understanding but also provides a clear workflow, helping users assess the reliability and limitations of gravity-derived structural maps in tectonic complex areas.