Major and trace element composition of the Maiganga coal in the Gombe sandstone of the Upper Benue trough was carried out with the aim of determining their source, paleoweathering/climatic conditions, tectonic setting and depositional environment. Nine (9) of the coal samples and two (2) of the non-coal samples were selected for analysis of major and trace elements. The combined Inductively Coupled Plasma- Mass Spectrometry (ICP-MS) and Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES)were used to analyze the samples. The thickness of the Maiganga Coal seams vary from 0.5 4.2 m with a lateral extent of 750 m. Analysis of the results through bivariate plots, pearson correlation and cluster analysis shows that there is a strong correlation between Na2O, K2O and TiO2 with SiO2 and Al2O3 and ash yield indicate a common detrital source while others with weak or negative correlations, are believed to be autothochnous. Similarly, trace elements such as Cu, Pb, U, Th, Sb, Bi, V, Cr, W, Sn, Sr, and Sc showed strong correlations with Al2O3 and with each other, indicating that they were derived syngenetically or epigenetically from the same detrital input to the precursor swamp. Those elements that showed negative or weak correlations like Mo, Ni, As, Cd, Co, Cu, Zn, Be, Zr and Tl may have been authigenic in origin.The trace element concentrations of the Maiganga coal falls within the range for world coals and the exceptionally low concentrations of Pb, Be, As, and U makes it less of a threat to the environment and health thereby improving its quality. The discriminant plot on the basis of oxide of Al2O3 and TiO2 revealed a provenance of intermediate composition with little input from mafic source which is also supported by the plots of Co/Th against La/Sc and Cr/Th against Sc/Th.Weathering processes at the source as determined by CIA and PIA values both suggest a dominantly high weathering in a humid environment. Low U/Th, Ni/Co, Th/U, Sr/Ba ratios and Ni/Co vs V/Cr plot suggest that the coals were deposited under oxic and suboxic conditions reductive littoral to brackish swamp environment during deposition. In addition, low Mo, U and {(CaO+MgO+Fe2O3)/(SiO2+Al2O3)} ratio indicates a deltaic depositional environment for the Maiganga coal.They were formed in a passive- margin tectonic setting.
Key words: Maiganga, Coal, Geochemistry, Provenace, Tectonic Setting, Depositional Environment.
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