Publications

Well completion strategy is a critical factor affecting oil recovery efficiency from an oil field. A brown field needs good artificial lift and enhanced oil recovery strategy to optimize the oil production. Minas Field has produced for more than 50 years with various completion strategies until pressure maintenance by waterflood beginning in early 1980 with inverted seven spot patterns. As the field has matured, the need for more intensive reservoir management has grown. Reservoir management application todayencompasses developing future strategies as well ashistorical data collection and improvement of datareliability. This paper presents a study about the reservoir management process in Minas field. The process relies on data preparation (production parameters), data validation, updating of geologic data, selection criteria review, success parameter review, and monitoring of process and result analyses. Data collection and data processing are divided into four levels: Level 1 (area), Level 2 (focus area), Level 3 (pattern), and Level 4 (well/layer). Three months were required to collect and process the data, evaluate the data and determine the strategy to be applied from Level 1 until Level 4. Another three months period was used to execute the workover programs for approximately 30 wells. Following the workover programs, production monitoring took one year. This reservoir management process applied in Area 3 of Minas Field has arrested the production decline trend from 15.4% to relatively flat production trend. Previous commingled sand completion strategy was changed to single sand completion strategy. The single sand target is the A1 sand, the most productive and the uppermost sand layer from five producing sands. Cumulative additional reserves gained from the conversion to single A1 sand production are 97.2 MBO with positive production trend every month.