Application of sequence stratigraphy for an enhanced hydrocarbon reservoirs correlation in “OSP” field Niger Delta, Nigeria

Abstract

The cost of drilling exploration and production wells is high and the price of crude oil in the capital market is fluctuating, therefore, there is the need to mitigate the risk of improper investigation of time/age-dependent reservoir rocks continuity within a field. Sequence stratigraphic analysis was carried out in OSP field with the aim of identifying and correlating hydrocarbon reservoirs that are deposited contemporaneously. Key stratigraphic surfaces (maximum flooding surfaces and sequence boundaries) were interpreted from biostratigraphic, well log and seismic data. Biostratigraphic interpretation subdivide the study area into three floral subzones-P780, P820 and P830. Three maximum flooding surfaces dated 10.4 Ma, 9.5 Ma and 7.4 Ma and four sequence boundaries dated 10.6 Ma, 10.35 Ma, 8.5 Ma and 6.7 Ma were identified. Three depositional sequences (sequences 1-3) were identified from the integration of the biostratigraphic, well log and seismic data. The identified key stratigraphic surfaces and depositional sequences were employed in the delineation and correlation of the hydrocarbon reservoirs which were found to fall within the highstand and lowstand systems tracts. Sequence stratigraphic correlation technique aided the local arrangement and geometries of reservoirs within the field and in locating potential reservoirs.

Sequence Stratigraphic Evaluation of Sediments Domicile in Day Field Located in the Onshore Central Swamp Depobelt of the Niger Delta, Nigeria

“…Four major sequence boundaries and three intervening Maximum Flooding Surfaces (MFS) were recognized to have been deposited within the shallow Inner-Neritic to the Middle-Neritic environments (Alege, 2017;Alege et al, 2020). Furthermore, Oyetade et al (2020) also identified key stratigraphic surfaces and depositional sequences to delineate and correlate potential hydrocarbon reservoirs in OSP field of the Niger Delta. This study seeks to improve on existing knowledge of sequence stratigraphy by delineating, correlating sequences and key stratigraphic surfaces to determine the environment of deposition of the sediments domicile in Day Field located in the onshore Central Swamp depobelt of the Niger Delta, Nigeria (Figure 1).…”