The Study of Development Level Classification for Strongly Heterogeneous Sandstone Reservoirs at Sea

Due to the strong reservoir heterogeneity, interlayer development effect of offshore sandstone reservoirs is uneven, the development level at different stages is not clear, reservoir potential is poorly understood. The traditional classification method uses the absolute standard of indicators to evaluate, and the scope of indicators is unified, which does not reflect the real development level. In this paper, the relative standard of development level classification is used to evaluate, increase reservoir comprehensive classification evaluation and well pattern adaptability evaluation for complex fault block reservoirs. Aiming at the characteristics of high-speed development of offshore oilfields, introduce recovery rate evaluation of remaining recoverable reserves to improving classification system. At the same time, the volume sweep coefficient of water drive is introduced to improve the problem that traditional theoretical water cut rise rate is too small. Based on the above researches, a new system of development level classification for complex fault block reservoirs is established. An oilfield is used as the research target area to carry out the development level classification. According to the evaluation results, the potential of oil formation in three development levels is large. Combined with the fine research results of remaining oil distribution, three adjustment wells are put forward to predict the cumulative increase of 239000 cubic meters of oil, which has successfully guided the fine exploration of oil field potential.