Palynofacies and Sequence Stratigraphic Studies of ODPX-1 Well, Offshore Western Niger Delta, Nigeria

Abstract

This work presents the result of an investigation from ODPX-1 well to understand the palynology, biozonation and paleoenvironment. Biostratigraphic studies has been carried out on twenty (20) cutting samples recovered from ODPX-1 well in South-South region of Nigeria, Niger Delta Basin. Samples were taken at 60ft interval ranging from 4420ft to 5560ft depth. The lithology of the studied well sections are comprising of shales, silts, sandstone having very fine to coarse grained sandstone beds. A total of 1,313 palynomorphs and 2,015 kerogen were recognized from which some were labeled for microphotography. The diagnostic marker palynofossils like Pachydermites diederixi, Crassoretitriletes Vanraadshooveni and Retibrevitricolporites obodensis were used for biozonation and dating of the analyzed sections of the wells. A middle to upper Miocene age was assigned to the studied section and the boundary sited at 5020ft; 4980ft. a key palynological zone established was P800, P720 and P850 and this zone is correlated with the broad Pan-tropical zone of Echitricolporites spinosus. Two palynofacies association (P-1 and P-2) have been recognized and range from distal shelf to marginal basin to proximal shelf in total a shallow marine environment. A sequence characterization was also identified based on the maximum abundance and diversity of palynomorphs and kerogen assemblage from the sequence stratigraphic analyses of wells.