Maximizingprofitability in Marginal Green Oil Fields Utilizing Key Developmentopportunities - A Case Study of ADNOC-Alyasat Petroleum

Abstract Marginal field development is a crucial process due to the incorporated challenges from exploratory to production phases. Hence, ALYASAT Petroleum has adopted a proactive and innovative approach to overcome the challenges of marginal field development and achieve its strategic objectives. The company utilized different development opportunities in marginal green fields to ensure Maximum recovery, minimum costs, low risks, and enhancing safety. These include designing and optimizing wells trajectories, lower and upper completion, and water flood project which resulted in 30% recovery factor. Integrated static and dynamic models of different reservoirs have been constructed to study field performance. The full field static model incorporated structural, stratigraphic, geologic, and petrophysical interpretations. Full field dynamic model was built including PVT, SCAL, and well data. The full field dynamic model was matched to static model OOIP and water saturation, production, and pressure profile. Different prediction scenarios were conducted to assess the sensitivity of well trajectory design, lower completion design, upper completion design of artificial lift installation, and water flood injectors on the field performance that maximize the recovery factor at optimum cost. The optimized marginal field opportunities were identified based on the prediction scenarios and applied in the field development strategy. Highly deviated is the optimum trajectory for new wells placement to explore different reservoirs and maximize the reservoir contact. Four producer wells achieved 17.5 million stock tank barrels (MMSTB) of oil, representing a recovery factor (RF) of 8.75% of the original oil in place (OOIP) and 29.5% of the field's ultimate reserve. ICD lower completion technology is the optimum technique to overcome the wellbore heterogeneity in terms of reservoir quality and saturation distribution. ICD improved both productivity and injectivity by delaying early water breakthrough to maximize the recovery factor and balancing the well injection rate across all the reservoirs. Due to the sharp production decline of producer wells after short period of time, ESP technology is the most applicable artificial lift technique for upper completion from day one to lift the fluids from wellbore to surface facilities. ESP achieved the production of 30 million stock tank barrels (STB) of oil. This achievement corresponds to a recovery factor of 15% from the original oil in place and accounts for 50.7% of the field's ultimate reserves. Peripheral water injection supports the reservoir pressure, improves the sweep efficiency, and increases the field productivity. Four flanked water injectors resulted in 11.7 million barrels of oil, representing a recovery factor of 5.85% from the original oil in place and 19.8% from the ultimate field reserve. As a result of this project, ALYASAT Petroleum has been able to increase the oil recovery factor by 30% and extend the field life 20 years.