Petrographic composition of coal within the Benue Trough, Nigeria and a consideration of the paleodepositional setting

Abstract The petrographic composition of Cretaceous-age coals hosted in the Benue Trough, Nigeria is presented and discussed terms paleodepositional settings that influenced coal-bearing formations. Trough a failed arm triple junction an inland sedimentary basin extends NE-SW direction from Gulf Guinea south, to Chad Basin north. A total twenty-nine (29) coal samples were obtained nineteen localities Upper (UBT), Middle (MBT), Lower (LBT). high average volatile matter yield, low ash calorific value (24.82 MJ/kg, on average), sulphur values indicate good quality deposits. organic dominated by vitrinite, reported at 59.3% volume (mineral-matter free). Variation was noted inertinite content across three sub-regions. Liptinite macerals not commonly observed studied absent MBT samples. Coal facies studies decipher paleoenvironmental conditions under which vegetation accumulated. Indices used are gelification index (GI), tissue preservation (TPI), ground water (GWI variations), (VI), wood (WI). Comparing array models applied, differ UBT LBT samples, concurring with data. formed upper deltaic drier piedmont plane depositional environment, while lower marsh wet forest swamp environment. All ombrotrophic paleomire. In view modified equations plots used, interpreting environments just single model reliable.