On June 29, the reporter learned from Daqing Oilfield that the Xingnan Development Zone of Daqing Oilfield has achieved remarkable results in overcoming the development challenges of poor reservoirs in Type III oil layers. The stage recovery degree of the poor reservoirs in the Sa II Formation reached 7.79%, exceeding the numerical simulation by 1.88 percentage points; the block recovery rate increased by 6.31 percentage points, with the overall stage recovery degree reaching 32.08%.

After years of exploitation in the Xingnan Development Zone, the potential of the main high-quality oil layers has gradually depleted, and the pressure to maintain stable production has increased year by year. The poor reservoirs in the Sa II Formation within the area are characterized by poor reservoir conditions, low permeability, and significant interlayer differences. In the past, the injection pressure could not be raised, the oil layers had weak water absorption capacity, and a large amount of underground reserves remained difficult to produce, which has been a persistent challenge limiting the improvement of the block recovery rate.

Bai Yuguo, Director of the Technical Management Office of the Seventh Operation Area of Daqing Oilfield's No. 5 Oil Production Plant, told reporters: "Thin and poor reservoirs are inherently weak. Simple water injection cannot effectively drive the oil, and extensive exploitation will only exacerbate interlayer contradictions. To awaken the dormant reserves, meticulous efforts must be made on both the injection and production ends, combined with targeted fracturing stimulation measures."

Based on the actual formation conditions, the technical team tailored a comprehensive treatment plan: on the injection end, fine layered water allocation was implemented to gradually increase the injection pressure and smooth the underground seepage channels; on the production end, the production system was simultaneously optimized to balance the output differences among layers; for wells with high seepage resistance and severe reservoir blockage, precise fracturing operations were carried out to expand the fluid flow space, adopting a well-specific strategy to compensate for reservoir deficiencies.

After the implementation of the entire set of combined measures, the injection pressure of the poor reservoirs in the Sa II Formation steadily increased, the scope of oil layer utilization continued to expand, and the originally low-efficiency poor reservoirs gradually transformed into stable production capacity. Bai Yuguo introduced: "We tracked the pressure, water cut, and fluid production changes of each well throughout the process, dynamically adjusted the scheme parameters, and step by step brought the utilization level of the poor reservoirs above expectations. Ultimately, all development indicators outperformed the model predictions."

The successful development of the poor reservoirs in the Sa II Formation has established a mature treatment pathway suitable for the thin and poor oil layers in Xingnan, which is replicable and scalable. It is reported that technical personnel will extend this model of injection-production adjustment combined with precise fracturing to similar well groups in the surrounding area, deeply tap the remaining potential of Type III oil layers across the entire zone, and rely on fine technical management to solidify the foundation for stable production in the old area, continuously boosting confidence in the oilfield's efforts to increase production.