[01] Ugwu Chinenye Martha, Department of Industrial Physics, Enugu State University of Science and Technology, Enugu, Nigeria. [02] Ugwu Gabriel Zeruwa, Department of Industrial Physics, Enugu State University of Science and Technology, Enugu, Nigeria.

Qualitative and quantitative interpretations of aeromagnetic anomalies over Ogoja and Bansara areas of Anambra Basin, Lower Benue Trough of Nigeria were carried out using Euler deconvolution and forward and inverse modelling methods. The study area which covers an area of approximately 6050 km² lies within latitude 6°0'0'' to 7°0'0'' North and longitude 8°30'00'' to 9°0'00'' East. The regional anomaly was separated from the total magnetic intensity field to obtain the residual anomaly using first order polynomial fitting technique. The edges and causative bodies of the residual anomaly were also sharpened to reduce anomaly complexity as well as fault trend amplification using first, second and horizontal derivatives. The result of the study shows thick sedimentary depth that is sufficient for hydrocarbon accumulation. The 3D basement topography map of the study area shows a linear depression with the deepest sedimentary thickness obtained at the Southeastern region (Bansara area). This implies that the prospect for hydrocarbon accumulation will be higher in Bansara area than in Ogoja. The deepest depths obtained from the results of the Euler deconvolution and forward and inverse modelling of the aeromagnetic data are 4511m and 4654m respectively. The magnetic susceptibilities of the intrusive bodies modelled by forward and inverse modelling techniques suggest the presence of minerals such as graphite and cassiterite as well as rock bearing minerals like limestone, granite and marble.

Euler Deconvolution, Forward and Inverse Modelling, Magnetic Anomaly, Sedimentary Thickness, Intrusive Bodies and Hydrocarbon Potentials

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