The potentials of accessory palynomorphs as sequence stratigraphic and basin evaluation tools in the shallow offshore Niger Delta

Abstract

Freshwater algae – Botryococcus and Pediastrum, marine indices – dinoflagellates and microforaminiferal linings, and charred Poaceae cuticles are accessory palynomorphs commonly recovered from Niger Delta sediments. The abundant recovery of these non-pollen palynomorphs necessitates a test of their usefulness for sequence stratigraphic purposes. Bio-sequence stratigraphic data and stratigraphic distribution trends of Botryoccocus, Pediastrum and marine indices as well as charred Poaceae cuticles from three oil wells from the offshore shallow Niger Delta were collated and evaluated against systems tracts as well as sequence stratigraphic surfaces - transgressive surface, marine flooding surface and sequence boundary. Results show that the ratio of Botryococus:Pediatsrum:Marine index, and charred Poaceae cuticles have reliable sequence stratigraphic value in the studied area. This value will help in sequence stratigraphic study of the area particularly in its sand-dominated sequences characterized by poor faunal contents typical of the offshore shallow Niger Delta.