Abstract

Palynological biostratigraphy and paleoenvironmental analysis of the sediments penetrated by OSM well in the Coastal Swamp Delta Depobelt of the Niger Delta Basin were conducted to determine the biozones, age, and depositional environment of the sediments. Three lithofacies were identified in the studied section based on the relative proportions of shale and sand across multiple intervals: sandy shale, shaly sand, and shale. A total of 803 palynomorphs, comprising 54 different species, were recovered. The palynomorphs is quantitatively dominated by land-derived species such as Verrucatosporites sp., Polypodiaceoisporites sp., Laevigatosporites sp., Acrostichum aureum, Retitricolporites irregularis, Zonocostites ramonae, Pachydermites diederixi, Sapotaceae, and Psilatricolporites crassus. Three palynological subzones were identified: P780, P770–P740 (undifferentiated), and P720. Significant biomarker events within the studied interval indicate a Middle Miocene to Late Miocene age. The presence of environment-specific palynomorphs suggests that the sediments were deposited in a terrestrial to coastal deltaic/inner neritic paleoenvironment.

Key words: Key words: Biozonation, Palynology, Paleoenvironment, Lithofacies, Terrestrial, Coastal