Abstract

Structural interpretation of aeromagnetic data over Nkalagu-Igumale area of the Lower Benue Trough of Nigeria was carried out to determine the depth to magnetic basement and delineate the basement morphology and the structural features associated with the basin and their trends. The aeromagnetic data were subjected to series of computer based image and data enhancement techniques before spectral analysis. Results of the 2-D spectral analysis revealed two depths source models with the depth model (D1) for deep magnetic source bodies which are associated with intra-basement discontinuities and faults ranging from 2.15 to 5.25 km while the depth model (D2) of the shallow magnetic source bodies range from 0.35 to 0.99 km. From an economic viewpoint, the results indicate possible mineralization and existence of a reasonable Cretaceous sedimentary thickness in the area which is deep enough for hydrocarbon accumulation. The average sedimentary thickness obtained in the area is 3.75 km.

Key words: Benue Trough, depth to magnetic basement, aeromagnetic data, spectral analysis, intrusive bodies.