Abstract

Aims: To assess the source rock characteristics and the depositional environment through Geochemical studies of sediment samples from the Upper Benue Trough. Place and Duration of Study: Department of Geology, Obafemi Awolowo University, Nigeria and The Activation Laboratory Ltd, Ontario, Canada between February 2011 and March 2012. Methodology: Eighteen samples made up of sand, shale, coaly shale, shaly sand and sandy shale, occurring between the depths of 18.3 m and 2725 m were analysed for thirty-four elements, comprising eight major, twelve trace, and fourteen rare earth elements (REE) using the Inductively Coupled PlasmaMass Spectrometry technique. Results: The results show that the sediments are compositionally rich in Al2O3 and Fe2O3. The low TiO2 values of compared to those of Post-Archean Australian average shale (PAAS) suggest that they were derived from more evolved felsic source rock. The relatively low average Rb/Sr and high Th/U ratios indicate that moderate to more intense weathering occurred in the source rock area. The absolute rare earth elements (REE) concentrations were in the order of coaly shale > shale > sandy shale > shaly sand > sand. Original Research Article British Journal of Applied Science & Technology, 4(20): 2931-2945, 2014 2932 Conclusion: The Al2O3/TiO2, Eu/Eu*, Th/Sc, La/Sc, Th/Co, La/Co, and Th/Cr ratios indicate that the sediments were probably derived from felsic source rocks. In addition, the high LREE/HREE ratios and the negative Eu anomaly also support felsic source rocks for the sediments whilst the very low V/Cr ratios indicate that these sediments were deposited under anoxic environment, consistent with the series of horst and graben structural framework model of the Benue Trough.

Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call