BIOSTRATIGRAPHIC STUDY OF INTERVAL 8929.00 FT – 9055.00 FT AT MULLER-1 WELL, GREATER UGHELLI, NIGER DELTA BASIN, NIGERIA

One hundred and twenty core samples were collected from Muller-1 Well, Greater Ughelli, Niger Delta Basin, Nigeria, at depth intervals between 8929.00 ft and 9054.00 ft for this study. Accuracy and dependability of results were ensured by maintaining standard procedures during analysis. The lithologic description of the samples indicates four lithofacies comprising shale, coal, clayey sand, and sandstone corresponding to the Paralic Agbada Formation. Sedimentological characteristics, including coarse to medium sandstone, coal, and shale intercalations, corroborate fluctuating energy conditions typical of deltaic systems. The sediments of the studied well were considered to be both marine and continental (land). Palynological and foraminiferal analyses were carried out on ten samples. The foraminiferal species that were recovered cannot be used for biozonation because of their paucity and non-diverse assemblage. Palynomorphs such as Verrucatosporites sp., Laevigatosporites sp., Monocolpites marginatus, Cyathidites minor, Longapertites sp., and Monocolpites sp., along with diatom frustules, Botryococcus braunii, and fungal spores, support a deltaic or estuarine environment interpretation. This suggests a paralic paleoenvironment that underwent a depositional shift from terrestrial rainforest vegetation to brackish swamp vegetation. Future research should continue to integrate diverse analytical techniques to enhance understanding of the complex depositional environments in more wells across the Niger Delta field.