Integrated Reservoir Characterization and Volumetric Re-evaluation of the ‘WOFEM’ Field Onshore Niger-Delta for Field Review

Abstract: As campaign is ongoing and efforts are put in place to increase the Nigeria total oil production rate above 1.75 million BOPD, it is expedient to carry out the petrophysical re-evaluation of some of the fields in order to understand the reservoir behaviour and possibly optimize production. In this work, all the hydrocarbon bearing reservoirs were mapped and correlated across the three (3) wells and the petrophysics were evaluated accordingly. This work reveals that there is decrease in the Net to Gross (NTG), porosity and the water saturation (Sw) with increase in depth. The decrease in the NTG of this field may be due to the frequent intercalation of the shale. The closer we approach the Akata Formation the more shaly the sand becomes. We can infer that the decrease in the porosity with increase in depth in this field is due to compaction as a result of the load of the overburden. The anomalies in the trend may likely be the resultant effect of the mud in the invasion zones. The NTG ranges between 0.43 and 0.98, Porosity ranges between 0.17 and 0.28 and the Sw ranges between 0.12 and 040. Three (3) reservoirs were selected for volumetric re-evaluation based on their NTG and porosity values. The B3 reservoir at the depth of 8243ft has the lowest volume Stock Tank Oil Initially in Place (STOIIP) with about 14.31MMBO while the C1 reservoir had the highest volume with a STOIIP of about 14.71MMBO.