Stochastic Facies Architecture, Spatial Anisotropy, and Implications for Potential Reservoir Connectivity in a Heterogeneous Fluvio-Deltaic System, Onshore Niger Delta, Nigeria

Authors

  • Chinaka J. C.
    Imo State University, Owerri
  • Nwosu I. E.
  • Nwofor O. K.
  • Agbodike I. C.
  • Ejiogu B. C.
  • David-Okoro I. L.

Keywords:

Stochastic facies modelling; Spatial anisotropy; Reservoir connectivity; Fluvio-deltaic reservoirs; Niger Delta.

Abstract

Reservoir connectivity in fluvio-deltaic systems depends on the spatial arrangement of sand bodies and shale barriers. This study examines the potential static geological connectivity of the C2000–D1000 and D1000–D2000 intervals in the Chinak Field, onshore Niger Delta, using well logs, seismic interpretation, structural modelling, variogram analysis, and Sequential Indicator Simulation. The available modelled net-to-gross (NTG) ranges are 0.53882–0.95224 for C2000–D1000 and 0.47117463–0.99902231 for D1000–D2000. Fitted horizontal variogram ranges of 1,234 m and a vertical range of 3.9 m give a horizontal-to-vertical correlation-range ratio of approximately 316.4. The facies-model illustrations suggest potentially greater lateral sand-body continuity in C2000–D1000 and more channel-scale variability and possible compartmentalization in D1000–D2000. These are qualitative interpretations of potential static connectivity, not measurements of connected sand volumes or evidence of dynamic fluid communication. The absence of cell-level facies-grid exports prevented calculation of component counts, largest connected components, connected sand fractions, and uncertainty across realizations.

Dimensions

Adeogun, O. Y., Ajewole, S. O., Folohunsho, O. Y., Adeoti, L., & Adelaja, A. T. (2025). Structural and 3D seismic attribute analysis for reservoir characterization in Pearl Field, offshore Niger Delta. Discover Geoscience, 3, Article 42. https://doi.org/10.1007/s44288-025-00150-5

Al-Mudhafar, W. J., Vo Thanh, H., Wood, D. A., & Min, B. (2024). Stochastic lithofacies and petrophysical property modeling for fast history matching in heterogeneous clastic reservoir applications. Scientific Reports, 14, Article 22. https://doi.org/10.1038/s41598-023-50853-3

Attouman, K. D. B., Adeleye, M. A., Osinowo, O. O., Nwakanma, A., & Agathe, Z. T. (2025). Reservoir description and modelling using integrated seismic and petrophysical data in AKDB field, offshore Niger Delta, Nigeria. Discover Geoscience, 3, Article 176. https://doi.org/10.1007/s44288-025-00292-6

Deutsch, C. V., & Journel, A. G. (1998). GSLIB: Geostatistical software library and user’s guide (2nd ed.). Oxford University Press.

Igonoh, D. A., Emujakporue, G. O., & Inichinbia, S. (2026). Reservoir characterization using integrated petrophysical evaluation, seismic attributes, and AVO modeling in JASMI Field, Niger Delta Basin. Nigerian Journal of Physics, 35(4), 42–58. https://doi.org/10.62292/njp.v35i4.2026.641

Jin, J., Li, S., Li, J., & Ding, F. (2024). Geological model calibration based on gradual deformation and connectivity function. Scientific Reports, 14, Article 29395. https://doi.org/10.1038/s41598-024-80363-9

Journel, A. G. (1983). Nonparametric estimation of spatial distributions. Mathematical Geology, 15(3), 445–468. https://doi.org/10.1007/BF01031292

Kuye, D. A., & Hampson, G. J. (2023). Sedimentological and tectono-stratigraphic characterisation of a shallow-marine reservoir, ‘Dona’ field, offshore Niger Delta. Marine and Petroleum Geology, 158, Article 106517. https://doi.org/10.1016/j.marpetgeo.2023.106517

Larue, D. K., & Hovadik, J. (2006). Connectivity of channelized reservoirs: A modelling approach. Petroleum Geoscience, 12(4), 291–308. https://doi.org/10.1144/1354-079306-699

Manzocchi, T., Walsh, D. A., Carneiro, M., & López-Cabrera, J. (2023). Compression-based facies modelling. Mathematical Geosciences, 55, 625–644. https://doi.org/10.1007/s11004-023-10048-y

Olaoluwa, A., Alabi, O. O., Ojo, B. T., & Sedara, S. O. (2025). Enhancement of reservoir characterization with petrophysical analysis of well log data in the “Abig” oil field, Niger Delta, Nigeria. Nigerian Journal of Physics, 34(4), 71–81. https://njp.nipngr.org/index.php/njp/article/view/451

Oyesomi, H. A., Oladele, S., Oyedele, K. F., Adeogun, O. Y., & Omolaiye, G. E. (2025). Siliciclastic reservoir characterisation and geometric trend modelling for hydrocarbon quantification and uncertainty analysis: A case study of Doma Field, Niger Delta Basin, Nigeria. NRIAG Journal of Astronomy and Geophysics, 14(1), 1–17. https://doi.org/10.1080/20909977.2025.2460326

Pyrcz, M. J., & Deutsch, C. V. (2014). Geostatistical reservoir modeling (2nd ed.). Oxford University Press.

Reijers, T. J. A. (2011). Stratigraphy and sedimentology of the Niger Delta. Geologos, 17(3), 133–162. https://doi.org/10.2478/v10118-011-0008-3

Short, K. C., & Stäuble, A. J. (1967). Outline of geology of Niger Delta. AAPG Bulletin, 51(5), 761–779. https://doi.org/10.1306/5D25C0CF-16C1-11D7-8645000102C1865D

Spina, V., Olagundoye, O., Chizea, C., Pellettier, J., Onyeanuna, C., Parsa, A., Joubert, T., Fashanu, M., Enuma, C., Ifihan, J. J., Epelle Ebenezer Seth, E. E., & Olabiyi, T. (2023). Unravelling the impact of geological heterogeneities in reservoir management: An integrated study of the deep-water Akpo Field, Niger Delta. Marine and Petroleum Geology, 150, Article 106132. https://doi.org/10.1016/j.marpetgeo.2023.106132

Spina, V., Amoyedo, S., Wibberley, C. A. J., Tozer, R., Ribes, C., Maia, R., Atoyebi, H., & Vincent, E. (2025). Characterization of a deep-water turbiditic reservoir under an active hydrodynamic regime (Niger Delta). Marine and Petroleum Geology, 172, Article 107185. https://doi.org/10.1016/j.marpetgeo.2024.107185

Strebelle, S. (2002). Conditional simulation of complex geological structures using multiple-point statistics. Mathematical Geology, 34(1), 1–21. https://doi.org/10.1023/A:1014009426274

Published

2026-11-06

How to Cite

Chinaka, J. C., Nwosu, I. E., Nwofor, O. K., Agbodike, I. C., Ejiogu, B. C., & David-Okoro, I. L. (2026). Stochastic Facies Architecture, Spatial Anisotropy, and Implications for Potential Reservoir Connectivity in a Heterogeneous Fluvio-Deltaic System, Onshore Niger Delta, Nigeria. Nigerian Journal of Physics, 35(S). https://doi.org/10.62292/njp.v35(S).2026.763

Issue

Vol. 35 No. S (2026): Nigerian Journal of Physics - Vol. 35(S)

Section

Articles
Copyright & Licensing

Copyright (c) 2026 Chinaka J. C., Nwosu I. E., Nwofor O. K., Agbodike I. C., Ejiogu B. C., David-Okoro I. L.

Creative Commons License

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

How to Cite

Chinaka, J. C., Nwosu, I. E., Nwofor, O. K., Agbodike, I. C., Ejiogu, B. C., & David-Okoro, I. L. (2026). Stochastic Facies Architecture, Spatial Anisotropy, and Implications for Potential Reservoir Connectivity in a Heterogeneous Fluvio-Deltaic System, Onshore Niger Delta, Nigeria. Nigerian Journal of Physics, 35(S). https://doi.org/10.62292/njp.v35(S).2026.763

Most read articles by the same author(s)