Hydrocarbon Recovery Enhancement and Well Placement Optimisation through Integrated Flow Pathway and Reservoir Connectivity Analysis in a Faulted Field
Keywords:
Hydrocarbon Recovery, Faulted Field, Fluid Flow Pathways, Structural Compartmentalisation, Well Placement OptimisationAbstract
Hydrocarbon recovery in a faulted field is strongly influenced by reservoir connectivity, fault seal behaviour, and fluid flow pathways. This study evaluates the impact of structural compartmentalization on reservoir performance and well placement optimization through an integrated analysis of fault architecture, reservoir correlation, and flow pathway characterization within a faulted hydrocarbon field. Four wells (X01, X02, X03 and X04) were examined for reservoir continuity, fault-controlled connection and implications for field development. The results of the reservoir correlation indicated the presence of two main reservoir units throughout the studied region. Wells X01, X03 and X04 show high lateral continuity, thicker development of sandstones and good reservoir quality. Well X02 is characterised by a deeper occurrence of the reservoir, lower thickness of sand and increased shale content. Structural study has shown four faults (F1–F4) that exert strong control on the architecture and connectivity of the reservoir. F1 and F2 are the main structural features, and F3 and F4 are minor faults. The most important fault, F1, with the greatest throw, separates the deeper downthrown X02 compartment from the structurally elevated and interconnected X01–X03–X04 reservoir system, but F2 retains connectivity within the latter compartment. The fault seal assessment shows that faults F1, F3, and F4 are sealing faults, but F2 is a non-sealing fault due to sand-on-sand juxtaposition. The seal F1 gives X02 good isolation from the associated reservoir system, and therefore compartmentalization and limited fluid contact. Flow pathway study shows that the connectedness of reservoirs in the X01–X03–X04 compartment facilitates efficient fluid migration and pressure communication, and therefore enhances the recovery capacity. The isolated X02 compartment offers less connectivity and development opportunities. The paper indicates that integration of fault seal analysis, reservoir connectivity assessment and flow channel characterization provides a robust structure to optimize well location, minimise development uncertainty and enhance hydrocarbon recovery in structurally complex reservoirs.
References
Adeoti, L., Onyekachi, N., Olatinsu, O., Fatoba, J., & Bello, M. (2014). Static reservoir modelling using well log and 3D seismic data in a KN field, offshore Niger Delta, Nigeria. International Journal of Geosciences, 5, 93–106. https://doi.org/10.4236/ijg.2014.51011
Amajor, L. C. (1991). The Niger Delta: Sedimentological evolution and petroleum geology. Journal of African Earth Sciences.
Avbovbo, A. A. (1978). Tertiary lithostratigraphy of the Niger Delta. AAPG Bulletin, 62, 295–300.
Azubuike-Ijomah, K., Adiela, U. P., & Moses, A. (2017). Petrophysical analysis and reservoir potential of Uku-1 well, X-Field, Niger Delta, Nigeria. International Journal of Advance Research and Innovative Ideas in Education, 3(4), 3282–3291.
Bretan, P., Yielding, G., Jones, H., & Lowry, P. (2003). Using calibrated shale gouge ratio to estimate hydrocarbon column heights across faults in the Niger Delta. AAPG Bulletin, 87(3), 397–413. https://doi.org/10.1306/09060201114
Bilotti, F., & Shaw, J. H. (2005). Deep-water Niger Delta fold and thrust belt. AAPG Bulletin, 89, 449–471.
Burke, K., Dessauvagie, T. F. J., & Whiteman, A. J. (1972). Geological history of the Benue Valley. African Geology.
Corredor, F., Shaw, J. H., & Bilotti, F. (2005). Structural styles in the deep-water fold and thrust belts of the Niger Delta. AAPG Bulletin, 89(6), 753–780. https://doi.org/10.1306/02170504074
Doust, H., & Omatsola, E. (1990). Niger Delta. In J. D. Edwards & P. A. Santogrossi (Eds.), Divergent/passive margin basins (AAPG Memoir 48, pp. 201–238). AAPG.
Evamy, B. D., Haremboure, J., Kamerling, P., Knaap, W. A., Molloy, F. A., & Rowlands, P. H. (1978). Hydrocarbon
habitat of the Tertiary Niger Delta. AAPG Bulletin, 62(1), 1–39. https://doi.org/10.1306/C1EA47ED-16C9-11D7-8645000102C1865D
Fossen, H. (2016). Structural geology (2nd ed.). Cambridge University Press.
Kulke, H. (1995). Nigeria. In H. Kulke (Ed.), Regional petroleum geology of the world. Gebrüder Borntraeger.
Lindsay, N. G., et al. (1993). Fault seal analysis in hydrocarbon systems. AAPG Bulletin.
Opara, A. I., Onuoha, K. M., Anowai, C. N., & Mamah, L. I. (2011). Geophysical and petrophysical characterization of reservoirs in parts of the western Niger Delta. International Journal of Physical Sciences, 6(14), 3479–3495.
Short, K. C., & Stauble, A. J. (1967). Outline of geology of Niger Delta. AAPG Bulletin, 51(5), 761–779. https://doi.org/10.1306/5D25C0CF-16C1-11D7-8645000102C1865D
Stacher, P. (1995). Present understanding of Niger Delta hydrocarbon habitat. SPDC Review.
Tuttle, M. L. W., Charpentier, R. R., & Brownfield, M. E. (1999). Niger Delta petroleum system. U.S. Geological
Survey.
Weber, K. J., & Daukoru, E. M. (1975). Petroleum geology of the Niger Delta. Proceedings of the Ninth World Petroleum Congress, 2, 209–221.
Whiteman, A. J. (1982). Nigeria: Its petroleum geology. Graham & Trotman.
Xiao, H., & Suppe, J. (1992). Origin of rollover anticlines. AAPG Bulletin.
Yielding, G., Freeman, B., & Needham, D. T. (1997). Quantitative fault seal prediction. AAPG Bulletin, 81(6), 897–917.
