The Nigerian Association of Petroleum Explorationists (NAPE) has called on oil and gas operators to adopt innovative strategies to maximise production from mature fields. This advice comes as the industry grapples with declining reserves and tight drilling budgets. NAPE's suggestion is based on the success story of ND Western's Utor-40 well in the Utorogu Field, Oil Mining Lease (OML) 34 in Delta State. The field has historically been gas-prone and is part of a joint venture with the Nigerian National Petroleum Company Exploration & Production Limited (NEPL).
The Utorogu Field, operated by ND Western, presented a challenge in maximising value from thin, stacked, and often saturated reservoirs that were bypassed in earlier development phases. According to Dr. Christopher Asuquo-Jackson, a member of NAPE and Head of Geoscience at ND Western, the company initially planned to complete the Utor-40 well as a single horizontal string targeting the E14 reservoir, with a forecast of 2,000 barrels of oil per day. However, after drilling and testing the pilot hole, the plan was revised.
The pilot hole drilling and testing revealed nine hydrocarbon-bearing reservoirs, opening a window to re-evaluate the original completion strategy. The integrated team, using petrology, petrophysics, reservoir engineering, and live drilling data, identified an additional saturated reservoir with a primary gas cap and an oil column that could be co-developed. This led to a revision of the completion plan to add a second zone. The initial plan was to achieve a maximum of 2,000 barrels per day from the E14 reservoir.
The revised completion strategy resulted in an additional 300 barrels per day, pushing the total delivery to over 2,000 barrels per day, with minimal incremental completion cost. This gain is significant, especially for marginal field operators where every barrel counts to cover evacuation and security costs. The Nigerian upstream oil and gas industry, where over 60 per cent of production comes from mature assets, can learn from this experience.
NAPE's advice is to adopt integrated subsurface evaluation and real-time drilling intelligence over rigid adherence to Field Development Plans (FDPs). FDPs are often treated as sacrosanct, but the Utorogu Field experience shows that flexibility can lead to increased production. The association's technical/business meeting in Lagos, where the case study was presented, aimed to share knowledge and best practices in the industry.
The Utor-40 well drilling experience in the Utorogu Field, OML-34, demonstrates the importance of leveraging integrated subsurface evaluation and real-time drilling intelligence to maximise reservoir value and optimise well delivery. The case study highlights the potential for increased production from mature fields with the adoption of innovative strategies. As the industry continues to face challenges, such experiences can provide valuable lessons.
The Nigerian Association of Petroleum Explorationists is promoting knowledge sharing and collaboration among industry stakeholders to address the challenges facing the upstream oil and gas sector. By adopting best practices and innovative strategies, operators can unlock more oil barrels from mature fields, contributing to the growth and sustainability of the industry. The industry can benefit from the experience of ND Western's Utor-40 well drilling, and NAPE's advocacy for integrated subsurface evaluation and real-time drilling intelligence.
Key points
- NAPE urges operators to adopt integrated subsurface evaluation and real-time drilling intelligence.
- The Utorogu Field experience shows that flexibility in Field Development Plans can lead to increased production.
- The industry can benefit from knowledge sharing and collaboration to address challenges facing the upstream oil and gas sector.
