The study is focused on the use of 3D seismic, well logs and checkchots data to delineate, evaluate and characterize reservoirs relating to their hydrocarbon potentials. Four localized wells were available for this study. The study location is Onka field, offshore, Niger Delta. Well correlation and detailed petrophysical analysis was carried out along all the wells. Three reservoirs were discerned within the agbada formation. Among these delineated reservoirs, reservoir 2 occurs to be the most prolific with average gross thickness of about 49ft, net pay thickness of about 43ft, average net to gross thickness of approximately 71%, a good porosity of 20% and hydrocarbon saturation of 81% which is more blatant in well DESLA 1ST2. Seismic interpretation shows the presence of 26 faults. The faulting system corresponds with the geology of the Niger Delta. From the generated structural surface map of Reservoir 2, Fault F7 at the flank of the crest forms an antithetic fault type with both F7A and F7B. This also aligns with the mundane trapping system of the study area. It is recommended that more wells should be drilled at strategic locations to provide more data that will contribute to quality reservoir models.
seismic, reservoir characterization, Niger-Delta, prospect evaluation, petrophysics, Onka field, offshore, geology
 Peng XD, Wang XG, Tong LY, Li H, Li H, Lv XD, Chen YX. (2015). A new method for deliverability evaluation of offshore gas reservoirs with high temperature and pressure. Environmental and Earth Science Research Journal 2(1): 1-6. https://doi.org/10.18280/eesrj.02010
 Li M, Sang Q. (2014). The research on the method of identifying low resistivity reservoir in Zhusan depression of the Pearl River Mouth Basin. Environmental and Earth Science Research Journal 1(1): 11-16. https://doi.org/10.18280/eesrj.010103
 Adeoti L, Onyekachi N, Olatinsu O, Fatoba J, Bello M. (2014). Static reservoir modeling using well log and 3-D 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
 Abe SJ, Ayuk MA, Mogaji K, Kafisanwo OO. (2018). 3D spatial distribution of reservoir parameters for prospect identification in ''Bizzy'' field, Niger Delta. Research Journal of Environmental and Earth Sciences 10(1): 24-33. https://doi.org/10.19026/rjees.10.5864
 Kukkle H. (1995). Regional petroleum geology of the world, Part II, Africa, America, Australia and Antarctica. Gebruder Borntraeger 1: 143-172.
 Tuttle MLW, Charpentier RR, Brownfield ME. (1990). Tertiary Niger Delta (Akata-Agbada) Petroleum System. United State Geological Survey, 3-5.
 Whiteman AJ. (1982). Nigeria, its petroleum geology, resources and potential. Springers Netherland 1: 165-394. https://doi.org/10.1007/978-94-009-7361-9
 Klett TR, Ahlbrandt TS, Schmoker JW, Dolton JL. (1997). Ranking of the world‘s oil and gas provinces by known petroleum volumes. United State Geological Survey Open-file Report, 97-463. https://doi.org/101.3133/ofr97463
 Kaplan A, Lusser CU, Norton IO. (1994). Tectonic map of the world, panel 10. American Association of Petroleum Geologists.
 Hosper J (1965). Gravity field and structure of Niger Delta, Nigeria, West Africa. Geology Society of American Bulletin 76(4): 407-422. http://doi.org/10.1130/0016-7606(1965)76[407:GFASOT]2.0.CO;2
 Avbovbo AA. (1978). Tertiary lithostratigraphy of Niger Delta. American Association of Petroleum Geologists Bulletin 62: 295-300. https://doi.org/10.1306/C1EA482E-16C9-1107-8645000102C1865D
 Weber KJ. (1987). Hydrocarbon distribution pattern in Nigerian growth fault structures controlled by structural style and stratigraphy. Journal of Petroleum Science and Engineering 1: 1–12. https://doi.org/10.1016/0920-4105(87)90001-5
 Doust H, Omatsola M. (1990). Petroleum geology of the Niger delta. Geological Society, London, Special Publications 50: 365–365. https://doi.org/10.1144/GSL.SP.1990.050.01.21