Spectral Depth Analysis of Parts of Bida Basin, North Central Nigeria, Using Aeromagnetic Data

Abstract

Spectral depth analysis of aeromagnetic data covering latitude 8.500N to 10.000N and longitudes 5.000E to 6.000E which corresponds to part of central Bida Basin, North Central Nigeria, was carried out for the purpose of investigating the sedimentary thickness beneath the subsurface. The study area was covered by six aeromagnetic maps. The aeromagnetic maps were digitized on a 37 by 37 grid and later compiled to produce a combined aeromagnetic data file for the area. The data file comprised 1369 data points. The polynomial fitting method was applied in the regional-residual separation. The residual map was later sub-divided into 16 spectral sections. The result of the study shows that the first layer depth was 1.8km while the second layer depth was 2.85 km with an average thickness of 2.0km. The maximum depth of 2.8km could be found at the South- Eastern part while the minimum depth of 1.8km could be found at North–Western part. Several depressions or variations in thickness have been observed in some parts of Bida Basin, particularly around Egbako and Pategi areas. These deeper sections of the Bida sedimentary basin identified in this study might be possible potentials sites for hydrocarbon deposits and is therefore recommended to be subjected to further geophysical method like seismic reflection/refraction, so as to ascertain its hydrocarbon potential.