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The Middle Benue Trough of Nigeria is filled with approximately 4000 m of Cretaceous sediments. Among these sediments are the Turonian±San-tonian organic matter-rich and coal-bearing strata of the Awgu Formation. Maceral analyses on 32 samples obtained from four boreholes and two outcrop sections from the Awgu Formation allow the subdivision of the coal beds and interseam sediments into three different petrographic/coal facies, namely: a vitrinite± fusinite coal facies, a trimaceritic coal facies, and a shaly coal facies. Vitrinite reflectance (VR) measurements gave values from 0.74 to 1.25% VR. These high VR values in such shallow boreholes arise as a result of the mid-Santonian tectonic episode during which the sediments were folded and faulted, accompanied by uplift. Coalification to the present rank was attained prior to this deformation. All the VR values fall within the zone of oil generation in source rocks. In the study area, however, oil generation potential can be expected only in the trimaceritic coal facies and some parts of the shaly coal facies which are rich in liptinite macerals. The vitrinite±fusinite coal facies with its high content of humic organic matter (vitrinite+inertinite) is likely to generate gas (wet+dry) only, within the given thermal maturity range.

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An integration of Landsat-7 ETM+, DEM and aeromagnetic datasets was used for basic surficial geologic mapping of the area of study. False colour composite and principle component analysis were derived from three separate bands each with same spatial resolution of 30 m, superimposed over one another. Visible and infra-red waves of the electromagnetic spectrum were sent out to the surface/near surface and the received impulses reveal areas with varying magnetic susceptibilities, displayed on the first vertical derivative map and areas that emitted ranges of heat radiation signatures, displayed on the analytical signal map. Lineaments were conversely extracted from these maps over an area of about 770 km 2. These lineaments represent fractures, faults, discontinuous quartz ridges, river channels, trenches and furrows in field. The eastern major fracture is the Kalangai major fault trending NE-SW. However, a possible presence of a mega fracture structurally controls River Karaduwa with other tributaries trending NW-SE, almost N-S. Part of the area also possesses gold mineralization potentials along the deep seated Kalangai major fault. The lineaments yielded from both datasets were integrated and showed a coincide results of the rate of deformation that most have affected the area to be of brittle/ductile form. The aeromagnetic data exhibits evidence of near surface fractures while the remote sensing data revealed more of surface fractures. Rose plots where inculcated and showed the dominant trend directions of the lineaments to be NE-SW and NW-SE.

Geological mapping was carried out and outcrop sections were examined alongside palaeocurrent directions from the greater part of the Campano-Maastrichtian outcrops in the Gongola Basin in Nigeria. Palaeocurrent measurements were obtained from asymmetrical ripples, cross bedding and dune bedforms within the channel-filling sub-facies of the Arowa Formation, and the foresets of the tabular cross bedding displayed in the Duguri formation. A north-westerly to a northerly paleocurrent direction was determined for the Arowa formation, indicating that the open sea was located to north-north-west, while a unimodal palaeocurrent directions characterize the Duguri Formation. These currents transported sediment into the Dukku, Akko and Bashar sub-basins with an overall centripetal pattern. The main structural features of the western part of Gongola Basin from E-W, are the N-S, NE-SW and NW-SE trending faults. These series of faults controll the basin subsidence and deposition of the Campano-Maastrichtian succession in the Dukku, Akko and Bashar sub-basins.The lateral and vertical facies variation within the Campano-Maastrichtian succession are in consistence with the northerly retreat of the sea.