Abstract: In order to explore the new mode of using residual oil, Ansai oilfield first used horizontal wells to encrypt the remaining oil, and 7 key technologies and field tests were carried out. Based on the different way of encryption horizontal well spacing and the transformation parameter study, the mechanism of remaining oil distribution was obtained and the technology of using remaining oil in high and medium water-bearing encrypted horizontal well adapted to Ansai low permeability reservoir was explored. It is proved that horizontal encryption can effectively use the remaining oil and low abundance reservoir between wells to utilize the remaining reserves of developed areas, which provides new enlightenment for the same reservoir to further improve the recovery rate.

Key words: Ansai oilfield, Remaining oil, Horizonatal well encryption, Lateral fracture, Water flooding advantage seepage paths

摘要： 为了探索动用剩余油新模式，安塞油田首次采用水平井加密动用剩余油，开展了7口加密水平井攻关研究和矿场试验。通过对不同加密水平井的布井方式、改造参数进行研究评价，揭示了剩余油分布机理，探索形成了适应安塞特低渗透油藏的中高含水期加密水平井动用剩余油技术。实践证明，水平加密能够有效动用井间剩余油和低丰度储层来动用已开发区域剩余储量，为同类油藏进一步提高采收率提供了新的启示。

关键词: 安塞油田, 剩余油, 加密水平井, 裂缝侧向, 水驱优势方向