Deformation Patterns of the Kaladgi Basin: Structural Constraints and Tentative Implications for Hydrocarbon and Uranium Exploration

ABSTRACT The Mesoproterozoic Kaladgi Basin, the northern part of the Dharwar Craton, represents an E-W trending intra-cratonic sedimentary basin that preserves a complex record of deformation within its sedimentary cover. This study examines the deformation patterns of the sedimentary cover in terms of structural geometry and kinematics to understand the tectonic processes that governed basin evolution. Detailed structural analysis reveals the coexistence of adjacent yet laterally overlapping compressional and extensional deformation domains within the cover sequence. The south-central part of the basin is characterised by folds, axial planar cleavage and faults defining a compressional regime with a dominant WNW-ESE to E-W structural grain. In contrast, the northern sector represents an extensional domain marked by homoclinal bedding, southerly dipping normal faults, conjugate tensile-hybrid joints and locally dismembered strata, sharing a broadly E-W structural orientation. A marked contrast exists between the deformation patterns of the sedimentary cover and the underlying basement. While the basement comprises largely undeformed granites in the north and poorly exposed Peninsular Gneissic Complex with a dominant NW-SE structural grain in the south, it shows little evidence of reactivation during cover deformation. This decoupling suggests that deformation of the sedimentary cover was predominantly thin-skinned in nature and likely driven by gravity gliding over a relatively rigid basement. The established structural framework provides tentative implications for mineral resource exploration. Fracture and joint networks in the extensional northern domain may have facilitated hydrocarbon migration, whereas fold culminations and antiforms in the south-central compressional domain could represent potential accumulation zones. Furthermore, the basement-cover unconformity emerges as a structurally favourable locale for unconformity-related uranium mineralisation, consistent with reported uranium anomalies from earlier studies.