Development of complex Upper Cretaceous carbonate reservoir of a mature onshore oil field in Abu Dhabi has been challenging because of higher pressure depletion, water cut and reservoir heterogeneities. 4D seismic reservoir surveillance technique is always challenging in carbonate reservoirs due to weak signal, therefore a feasibility study is carried out with the objective of identifying pressure depletion and the bypass oil zones subjected to different duration of production/water injection (WI) interval. Monitor seismic surveys are modeled from elastic properties derived from reservoir properties simulated at different periods using a calibrated Petro-elastic model. Seismic data acquired in 2007 is taken as base survey for monitoring field depletion during 14 years of production and future production/WI over a period of 2 to 9 years. 4D seismic amplitude attribute, "Envelope (monitor)-Envelope (base)" and "time-shift" are found above the repeatability noise (~10%) and detectability limit of 0.149ms respectively over a period of 14 years of production and 9 years of production/WI period. Technique is not found feasible over 2 years of Pilot WI period because of poor 4D signal to be detectable. 4D signals are dominantly controlled by accelerability law taken from the worldwide analogue and hence a pilot 4D monitor survey is recommended for the calibration of pressure law thereby consolidating the concept before implementing it on full field scale for optimizing the infill producers as well as water injectors.

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