Development of mature oil fields - A review

Development of mature oil fields has been, and will increasingly be, an attractive subject. Mature field development practices can be divided into two major groups: (I) well engineering and (2) reservoir engineering. This paper focuses on the reservoir engineering aspects. An extensive review of previously reported reservoir management practices for mature field development is provided. After the definition of mature field and an overview, different aspects of mature field development are outlined. The first issue covered is the estimation of remaining reserves focusing on the determination of the amount and location of the residual oil after primary and secondary recovery using field, log, and core data. After valuing the remaining oil, methods to recover it are classified. They include tertiary recovery, infill drilling, horizontals, optimal waterflooding design for mature fields, optimal well placement and other reservoir management practices. Suggested or implemented field application examples for big fields owned by majors and small fields owned by independents are presented. Special attention is given to tertiary oil recovery. An extensive review and critical analysis of tertiary recovery techniques covering the theoretical, practical, and economical aspects of it are provided. The emphasis is on their applicability in mature field development in terms of effectiveness (incremental recovery) and efficiency (cost and recovery time). Laboratory and field scale applications of different tertiary recovery techniques, i.e., gas (double displacement, WAG, and miscible-immiscible HC, CO2, and N-2) chemical (dilute surfactant, polymer, and micellar injection), and thermal (air and steam) injection, conducted to develop mature fields are included. Specific examples of big/giant fields, fields producing for decades, and mid to small size fields were selected. Differences in reservoir management strategies for majors, independents, and national oil companies are discussed. (c) 2006 Elsevier B.V. All rights reserved.