PGS Releases PSDM Data for Nigeria Library Rejuvenation

This depth reprocessing focuses on the northwestern Nigerian offshore, rejuvenating two datasets: the Nigeria MegaSurveyPlus and OPL 314/315/321/323 MC3D.

The 2023 PSDM provides coverage over three blocks available as part of the Nigeria Mini Bid Round 2022: PPL-303-DO, PPL-304-DO, and PPL-305-DO. The data also covers two adjacent, unlicensed blocks to the north (OPL 321 and OPL 323).

New understanding is available for two main structural provinces that are directly linked to the gravity-driven movement of the Akata Shale Formation. The eastern part is in the transitional detachment fold zone and contains subtle faulting along with low wavelength folding of Eocene to Quaternary stratigraphy. The west of the survey, situated in the outer fold and thrust belt, is characterized by closely spaced thrust faults.

The Niger Delta Basin is dominated by up to 12 km of Late Cretaceous to Quaternary-aged clastics, deposited in an upward-coarsening regressive deltaic sequence. The main source rocks are Akata Formation marine shales and Lower Agbada Formation paralic shales. Proven reservoirs in the basin are formed of unconsolidated sandstones of the Agbada Formation deposited as stacked turbidite channel and fan complexes. The largest accumulations are trapped in roll-over anticlines in the hanging walls of growth faults, but hydrocarbons may also be found in fault closures and subtle stratigraphic traps.

Through PSDM reprocessing, enhanced imaging of targets relevant for the 2022 mini bid round has been achieved with improved illumination of complex structures associated with the diapiric movement of the Akata Shale Formation. The broadband reprocessing has provided seismic data that is rich in frequency content, with a comprehensive velocity model enabling clearer imaging of structures, faults, and traps. AVO-compliant pre-stack data also helps to reveal subtle depositional features, significantly derisking exploration.