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

Abstract

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.