Evaluation of the Hydrocarbon Potentials of Shale Exposures at Okpekpe in Edo North

  • Alexander Ogbamikhumi University of Benin
  • Nosa Igbinigie University of Benin
  • Ovie Odokuma-Alonge University of Benin
Keywords: Organic-Geochemistry, Biostratigraphy, Source-Rock, Okpekpe, Anambra-Basin

Abstract

This study evaluates the source rock characteristics of rock exposures along a newly exposed road cut in Okpekpe. An integrated technique of organic geochemical analysis and biostratigraphy evaluation were adopted to determine the source rock quality, Maturation index, kerogen types, depositional environment andsediment age.

Results of organic geochemistry gave total organic carbon (TOC) value between 0.81 to 3.04 w.t% (2.08wt.% average) indicative of a good source potentials. The plot of Total Sulphur Content (TSC) against TOC suggests a transitional depositional environment for the samples while the plot of hydrogen index (HI) against oxygen index (OI) shows that the samples are capable of generating mixed type II/III kerogen.

Palynological analysis revealed that the basal section of the exposure is characterized by the occurrences of typical and moderately rich Late Cretaceous – Early Tertiary palynomorphs. While the upper section is poorly rich  in palynomorph abundance but with spot occurrences. The palynomophs asssemlages is of Late Maastrichtian - Early Paleocene and the outcrop is characterized by the presence of terrestrial pollens and spores indicating a continental to transitional depositional environment, typical of the Mamu Formation of the Anambra Basin.

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Published
2019-12-30