Abstract

This study presents a comparative analysis of joint gravity-magnetic inversion against separate gravity and magnetic inversion techniques to enhance subsurface imaging within the Wajrakarur Kimberlite Field (WKF) area in Eastern Dharwar Craton. Traditional separate potential field inversions, while fitting observed data, often produce geologically inconsistent and ambiguous subsurface models due to inherent nonuniqueness. The proposed research addresses this limitation by employing a cross-gradient joint inversion strategy, which couples the density and magnetic susceptibility models by incorporating structural similarity between them. This integrated approach yields a geologically consistent interpretation, significantly reducing ambiguity in subsurface imaging. The enhanced coherence in 3D joint models, evident in the consistent spatial correlation of density and magnetic susceptibility anomalies up to 5 km depth, robustly delineates key deep-seated features like volumetric mafic doming and distinct crustal block interfaces. This also provides sharper definition for shallower lithologies (e.g., PGC-II, Greenstone belts) and structural controls. Such clarity, confirmed by comparative model slices and tighter petrophysical clustering in cross-plots, offers critical insights for understanding kimberlite emplacement mechanisms and optimizing mineral exploration targets in complex cratonic settings.