Interpretation of High Resolution Aeromagnetic Data for Basement Depth estimates in Northwestern Nigeria: A preliminary Assessment for Energy Prospectivity

Abstract

Energy source diversification and sustainability is no longer a slogan but a necessity in Nigeria, this, work on geophysical exploration for oil and gas in Northern part is in line with the target for diversifying energy exploitation beyond Niger Delta region for economic reason. The Total Magnetic Intensity (TMI) data covering the study area of longitudes 3.50 oE and 7.00 oE and latitudes 10.00 oN and 14.00 oN was divided into thirty seven blocks of 55 km by 55 km for the purpose of twodimensional Fourier analysis in order to estimates depth to the basement in the area. Results from spectral analysis indicated two magnetic source depths, which account for deeper and shallower magnetic sources. Linear segment from the low frequency portion of the spectral plot is due to deeper source effects, representing the depth to the top of magnetic source (H2) interpreted as sedimentary thickness varies between 0. 47 km and 3.05 km. The sedimentary thickness increases from the south to north, temperatures at depth for each section were also estimated in line with Fourier’s law of heat conduction in the crust. These results agree with earlier geophysical work done in the area, which revealed that the area is not potentially viable for fossil fuel energy.