Analysis of High Resolution Aeromagnetic (HRAM) Data of Lower Benue Trough, Southeastern Nigeria for Hydrocarbon Potential Evaluation

Abstract:

The analyses of High Resolution Aeromagnetic (HRAM) data acquired over the lower part of the Benue Trough in southeastern Nigeria have delineated sections of the basin with requisite sedimentary thickness that could support the generation of oil and gas from right-type organic-matter rich source rock through geothermal gradient. The study likewise identified intra-sedimentary structural framework that could aid hydrocarbon migration and restrain generated hydrocarbon within available reservoirs. The susceptibility and Analytic Signal (AS) maps derived from the processed Guassian filtered and Reduced to Pole at Low Latitude (RTPLL) aeromagnetic data of the basin discriminate crystalline basement rocks from the sedimentary units as well as identified the boundaries of rocks with contrasting magnetic contents. The Centre for Exploration Techniques (CET) grid analyses of processed Tilt Derivative (TDR) and the Horizontal components of the Tilt Derivatives grids at different Upward Continuation distances enhances and delineates many relatively shallow, short (900 – 1600 m) intra-geologic terrain linear structures and fewer long, deeper (>1.5 – 43 km) inter-geologic terrains crustal linear structures which reduce in population but increase in lateral extent and depth with increasing continuation distances. Euler Deconvolution depth weighting analyses determined depth to magnetic sources which ranges in value from 120 m above to 5 km below the Minna reference datum, thus determine sediment thickness above the basement rocks. Regions having sedimentary thickness in excess of 3 km with active intra sedimentary structural elements were identified as regions to focus further petroleum exploration campaign on for petroleum prospect development through detailed geophysical and geologic investigations.