Robust Joint Inversion of Gravity and Magnetic Data Using an Lp‑Norm Cross‑Gradient Strategy in Complex Volcanic Terrains

Abstract

In early‑stage exploration for minerals, hydrocarbons, and geothermal resources, potential geophysical methods such as Gravity and Geomagnetic surveys stand out for their efficiency, rapid data acquisition, and cost‑effectiveness. Despite their advantages, the interpretation of data derived from these methods is often challenged by the non‑uniqueness of the solution, leading to potential
biases in the subsurface models without the support of additional geological or geophysical data. Our study was initiated by developing forward models based on synthetic gravity and magnetic data configured for volcanic terrains anomaly scenarios. This approach facilitates the evaluation of inversion algorithms to mitigate the inherent non‑uniqueness of potential method‑derived
models. The main objective of our research is to integrate comprehensive regional geological knowledge, which significantly enhances the accuracy of subsurface interpretations when combined with advanced geophysical techniques. This synergy is further exemplified by applying an Lp‑Norm fast 3D cross‑gradient joint inversion strategy, leveraging gravity and magnetic data to optimize computational efficiency while refining anomaly delineation. Notably, our strategy incorporates a hexahedral terrain model to account for gravitational and magnetic effects of complex terrain, marking a significant advancement in the field. Our findings demonstrate that a nuanced understanding of geological conditions, when integrated with a robust geophysical framework, can lead to the successful reconstruction of volcanic complex subsurface models. This breakthrough has profound implications for geothermal exploration, mineral exploration, and volcanic studies, offering a novel pathway toward more accurate subsurface exploration techniques.