No abstract

2-D modeling of high-resolution aeromagnetic data over the area investigated was carried out with the aid of Oasis MontajTM software in order to get the total magnetic intensity map as well as the residual map from where the modeling was carried out. The data was acquired for Nigeria Geological Survey Agency (NGSA) in 2010 by Fugro international of Netherlands. The specifications of the data were terrain clearance of 80 m, flight line spacing of 500 m and a tie line spacing of 5000 m. The area investigated in this work is located between longitude 120 00' - 130 30' E and Latitude 80 00' – 100 00'N. GM-SYS module of the Oasis montaj was used for this research, with depocentres, structural patterns, basement geometry and morphology as well as estimates of the physical character of the cause to an investigated anomaly determined. The models reveal the horst and graben structures of the basement and the various faults that segmented the area into block patterns. The results revealed sediment thickness in the range of 2-5 km for the models which are in agreement with the results obtained by various researchers in the area. Horst and graben were identified in the models which confirmed the rifting nature of the Benue Trough. The authors of this research are of the view that these depocentres, structural patterns and basement geometry may be a promising site for hydrocarbon traps and reservoirs. Keywords: Aeromagnetic Data, GM-SYS, Modeling, Horst, Graben.

With a renewed interest to search for hydrocarbons in the hinter land of Nigeria’s inland basin climaxed after the discovery of a rewarding oil prospects around the Kolmani river II as recently announced by the National Oil Company, the Nigeria National Petroleum Corporation (NNPC). This research was based on analyzing the high-resolution aeromagnetic data over the study area using the Oasis Montaj TM software, in order to get the total magnetic intensity map as well as the residual map, band pass filter map was used to generate magnetic aureoles. GM-SYS module of the Oasis montaj was used for the modeling exercise, the models reveal the horst and graben architecture of the basement with the grabens serving as depocentres, hydrocarbon potentials of the area were highlighted using magnetic aureoles mapping.

High-resolution aeromagnetic data investigation was carried out over the Gongola basin upper Benue trough northeastern Nigeria. Total intensity magnetic map were processed to get the residual map, reduction to equator, polynomial fitting, radially average power spectrum (RAPS) were done, subsequently the first horizontal and first vertical derivatives of the data was carried out in order to identify linear structures (faults and fractures). The outcomes from both the horizontal and vertical derivatives give contact locations that are continuous, thin and show major structures in the NE-SW direction both in the maps and in the rose diagrams. The study focused on delineation of geological structures such as rock contacts; rock boundaries, fractures and faulted zones from the maps, they are principally important in mineral resources studies because many of these resources are located along fracture zones. Linear structures perceived in this kind of studies are also reliable indicators for geologic structures. The result of this work is also significant in identifying areas to be avoided when constructing bridges, dams as well as siting nuclear power plants and delineation of potential risk areas of natural hazard. Keywords: Aeromagnetic Data, first Horizontal Derivative, first Vertical Derivatives, Gongola Basin, Linear Features.