Moderate heat-flow sedimentary basins are increasingly considered viable geothermal targets, particularly where mature hydrocarbon infrastructure reduces exploration risk. However, structural controls on conductive heat-flow distribution and associated uncertainty remain insufficiently quantified in foreland settings. This study develops an uncertainty-bounded thermo-tectonicframework for geothermal evaluation in the Upper Assam Basin, northeast India. Corrected bottom-hole temperature data from 34 deep wells are analysed using multiple empirical correction methods to construct a P10–P50–P90 temperature envelope, and conductive heat flow is calculated usingdepth-dependent harmonic bulk thermal conductivity accounting for lithologic layering. Statistical analysis and thermotomographic modelling are used to evaluate the relationship between basement architecture and thermal structure. Conductive heat flow ranges from ∼41 to 108 mW m−2, with most wells clustering between 60 and 75 mW m−2, consistent with a moderate foreland geothermal regime. A statistically significant inverse relationship between basement depth and conductive heat flow (Pearson r = −0.61 to −0.66; Spearman ρ = −0.71; p < 0.001) suggests that sedimentary thermal blanketing exerts first-order control on basin-scale heat distribution. Reservoir temperatures of 120–170 ◦C at depths of 3.4–4.6 km support screening-level geothermal development using binary-cycle technologies. The study formalizes a foreland oilfield geothermal play model that links basement geometry, sediment thickness, reservoir architecture, and structural permeability to geothermal prospectivity. This framework extends geothermal evaluation beyond local resource appraisal and provides a transferable methodology for screening moderate heat-flow foreland basins worldwide.