Abstract
Spectral depth analysis was carried out on ten (10) of the 2009 total magnetic field intensity data sheets covering some segments of the Bida basin, to determine the depth to magnetic basement within the basin. The data was obtained from the Nigerian Geological Survey Agency and used to produce a composite map of the study area which is situated within latitude 8 0 00'N - 10 0 00'N and longitude 4 0 30'E - 7 0 00'E. Sixteen (16) overlapping blocks were generated from the ten sheets and Spectral depth analysis was performed on each of the blocks. The results delineated two prominent magnetic zones of shallow and deeper depths with the depth to the shallow magnetic sources (h 1 ) ranging from 0.254km on Block 9 to 1.719km on Block 2, having an average depth value of 0.968km. The depth to the deeper magnetic bodies, h 2 , on the other hand, varies between 1.830km on Block 10 and 4.615km on Block 15, with an average value of 3.063km. The shallower magnetic sources were attributed to near surface magnetic sources which could be laterite, ironstones or ferruginous sandstones that intruded into the sedimentary basin close to the surface. The places with deeper magnetic sources were ascribed to intrusions of the magnetic basement into the basin at deeper depths, lateral discontinuities in the basement and other features differing in magnetic susceptibilities such as dykes, faults, fractures, horsts and grabens within the study area. Based on these results, the Kainji (1), Fashe (2), Mokwa (4), Egbako (5), Baro (7), Patigi/Baro (14) and Baro/Gulu (15) spectral blocks with sedimentary thickness values above 3.0km show the greatest potential for hydrocarbon accumulation. Keywords: Spectral Analysis, Depth to Magnetic Sources, Aeromagnetic data
Highlights
Data Acquisition: The 2009 IGRF corrected total magnetic field intensity data was acquired from the Nigeria Geological Survey Agency through the Ibrahim Badamasi Babangida University, Lapai Hydrocarbon Research Project which granted a third party access for the use of the data, while Oasis montaj 9.1 Software was used for the analysis and the Spectral Depth Analysis Method to determine the depth to basement rocks
Spectral Depth Analysis was applied to the total magnetic field intensity data covering parts of Bida Basin to determine the depth to basement rocks as well as the basement morphology
The data was divided into sixteen (16) overlapping spectral windows or ensembles (Figure 3) and Fast Fourier Transform (FFT) performed on each of the windows to decompose the anomalies into their energy and frequency components after which the radial power spectrum was calculated for each of the grid points
Summary
The Batati formation constitutes the uppermost units in the sedimentary sequence of the Bida Basin It consists, according to Obaje et al (2013), of argillaceous, oolitic and goethitic ironstones with ferruginous claystone and siltstone intercalations and shaly beds which occur in minor proportions some of which have yielded near shore shallow marine to fresh water fauna. The outcrops of the Patti Formation occur between Koton-Karfi and Abaji This formation consists of sandstones, siltstones, claystones and shales interbedded with bioturbated ironstones with the argillaceous units predominating in the central parts of the basin. The Agbaja Formation forms a persistent cap for the Campanian Maastrichtian sediments in the Southern Bida Basin as a lateral equivalent of the Batati Formation on the northern side of the basin It consists of sandstones and claystones interbedded with oolitic, TSEPAV, MT; MALLAM, A concretionary and massive ironstone beds in this region
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
