Integrated Approach to Reserve Estimation and Reservoir Simulation of ENI Offshore Field, in Niger Delta Nigeria
J. O. Ayorinde *
Department of Geology and Mineral Sciences, University of Ilorin, Nigeria.
O. O. Osinowo
Department of Geology, University of Ibadan, Nigeria.
P. Nwankwo
Department of Geology, University of Ibadan, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
Two producing reservoirs (H10 and E40) in Eni field Offshore Niger Delta were studied with intent to enhance their rate of recovery while mitigating water production. The material Balance software MBAL was used to estimate the Stock tank oil reserves and then compared to reserve estimates determined by both deterministic and stochastic techniques for improved validation. The MBAL model was also used to identify positions of fluid contacts and determine predominant drive mechanisms. These serve as guide in making informed decisions towards if and how best to economically produce remaining unproduced oil in place. Input parameters were average values derived from core and well logs analyses.
History matching of historical data enabled forecasts of possible future production life and volume at multiple scenarios.
Final outcomes show that after sixteen and forty five years of continuous production from the reservoirs studied (H10 and E40, respectively), remaining unproduced oil in place are still significant and can be economically produced by infill wells, which will in return increase the average production by nothing less than 33% of remaining oil in place, a substantial value bearing in mind the growing demand for oil, gas and other energy sources to lessen the apparently unquenchable world energy needs.
Keywords: Reserve estimation, reservoir simulation, ENI offshore field, reservoirs