Biostratigraphy of the nzam-1 well in the nkporo formation, anambra basin, southeastern Nigeria

This study presents a thorough biostratigraphic analysis of the Nkporo Formation in the Nzam-1 well, aiming to evaluate the age, paleoenvironment, and biozonation of the source rock penetrated by the well using palynological analysis.A total of 17 samples from the Nzam-1 well were subjected to palynological studies.The occurrence of diverse palynomorphs provides a framework for evaluating the age, paleoenvironment, and biozonation of the formation.The assemblage of forms (pollen, spores, and dinoflagellate cysts) indicates that the shales deposited in the Nzam-1 well range between Late Cretaceous, possibly Albian to Maastrichtian age.The presence of these fossils also suggests that the Nzam-1 well represents a marine depositional environment, which can support hydrocarbon generation.Palynomorph distribution analysis (Figure 1) reveals varying abundances across depth intervals, with peak occurrences in the 2411-2438 m zone.Age zonation (Figure 2) demonstrates clear biostratigraphic subdivision from Campanian to Maastrichtian intervals.Paleoenvironmental reconstruction (Figure 3) indicates a marginal marine setting with significant terrestrial input, favorable for organic matter preservation and hydrocarbon source rock development.