ISSN: 2642-1283
Authors: Dairo VA* and Oyewole EO
Palynomorphs were employed in this study to deduce the palynozones, age and paleoenvironment of an exploratory well drilled in the Niger Delta area. Sixty (60) ditch cutting samples were selected at intervals of 60ft from the depth of 6110ft to 11690ft and subjected to palynological laboratory analysis. The residual samples which comprise of Particulate Organic Matter (POM) were identified under optical microscope and the information from the abundance of pollens and spores identified were imputed into the Stratabug software. The lithostratigraphy of the section penetrated by the well comprises of intercalation of sandy mudstone, argillaceous sandstone to coarse sandstone. Also, a total of one hundred (100) palynomorph species were identified, out of which some marker species such as Botryococcus braunii, Laevigatosporites sp, Striatopollis catatumbus, Stiamoncolpites rectostriatus, Peregrinipollis nigericus, Cicatricosisporites dorogensis, Verrucatosporites sp, and Pachydermites diederixi were identified. This was followed by biozonation with the aid of standard zonation scheme and four (4) zones of pollen and spores comprising of P540, P560, P580 and P5620 were identified based on the Last Downhole Occurrence (Base) and First Downhole Occurrence (Top) of some marker species. Based on the palynozones identified, the age of the sections penetrated by the well ranges from late Oligocene to early Oligocene, which falls within the Rupelian and Chattian stage while the paleoenvironmental studies of the abundance and diversity of pollens and spores with respect to their environment, shows that most of the species falls within the Brackish water and the Freshwater swamps environments.
Keywords: Palynomorphs; Biozonation; Species; Oligocene; Palynozones
