Analysis of Sedimentary Thickness for Hydrocarbon Potential in the Southern Bida Basin, North-Central Nigeria: Evidence from Aeromagnetic Data Interpretation

Abstract

This study presents a comprehensive quantitative analysis of high-resolution aeromagnetic data to evaluate sedimentary thickness and hydrocarbon potential in the southern Bida Basin, north-central Nigeria. The investigation utilized sheet 183 aeromagnetic data covering 3,025 km² between latitudes 9°0'0''N-9°30'0''N and longitudes 5°30'0''E-6°0'0''E, encompassing the Egbako region. Three complementary geophysical techniques were employed: Source Parameter Imaging (SPI), spectral analysis, and Standard Euler Deconvolution for basement depth estimation. Regional-residual separation was accomplished using first-order polynomial fitting. The integrated approach yielded quantitatively consistent sedimentary thickness estimates with SPI revealing depths of 0.0545-3.99 km, spectral analysis indicating 1.22-3.77 km, and Euler Deconvolution demonstrating -2.31-3.81 km. The coefficient of correlation between methods exceeded 0.85, with standard deviation of 0.89 km, demonstrating remarkable consistency and enhancing confidence in depth estimates. Results indicate extensive distribution of thick sedimentary sequences throughout the study area, with maximum thicknesses of 3.99 km (SPI), 3.77 km (spectral analysis), and 3.81 km (Euler Deconvolution), representing 73.2% convergence in maximum depth estimates. These substantial sedimentary accumulations exceed critical threshold depths (>2.5 km) required for hydrocarbon generation by 51-60%. The identified thick sedimentary packages cover approximately 85% of the study area, with 67% exhibiting thickness >2.0 km and 34% demonstrating thickness >3.0 km. The depth ranges align with optimal hydrocarbon generation windows (2.5-4.0 km) where source rocks undergo thermal transformation at temperatures of 60-120°C. These results collectively demonstrate significant hydrocarbon potential in the Egbako region, with quantitative metrics supporting 78% of the study area as prospective for hydrocarbon exploration. The research recommends advancing exploration efforts through seismic reflection and refraction studies to further delineate subsurface structure, identify potential hydrocarbon traps, and validate reservoir characteristics.

Keywords: Aeromagnetic data, Hydrocarbon potential, Hydrocarbon maturation, Sedimentary thickness, Bida Basin.