缝洞型油藏剩余油分布预测及挖潜技术对策

Residual oil distribution prediction and potential tapping in fractured-vuggy reservoirs

李成刚 张炜 程洪 蒋林 陈彬滔 马国建 王幼 张准行

Li Chenggang Zhang Wei Cheng Hong Jiang Lin Chen Bintao Ma Guojian Wang You Zhang Zhunxing

中国石化 西北油田分公司 塔河采油三厂, 新疆轮台 841604 2. 中国石油勘探开发研究院 西北分院, 兰州 730020

NO.3 Tahe Oil Plant, SINOPEC Northwest Company, Luntai, Xinjiang 841604, China 2. Northwest Branch of Research Institute of Petroleum Exploration and Development, CNPC, Lanzhou, Gansu 730020, China

塔河油田缝洞型油藏非均质性强,油井开发递减较快,油藏采收率较低.在缝洞型油藏地质特征和开发特征分析的基础上,提出在缝洞单元内部划分单井流动单元的概念,同时结合油藏开发方式,在地质认识上对剩余油富集区进行预测.物性相对较差能量相对较弱局部充填封隔部位,水淹部位侧翼和局部构造高位置,注水开发后油藏中低效替油部位,水驱死角区域以及各个单井流动单元之间连通程度较差部位是剩余油富集区.这些剩余油的开采,对于供液能力和能量下降油井,注水采油和可控性大型压裂仍是有效手段;针对水淹井或者初期注水失效井,实施排水采油或者水力扩容技术;注入N2或CO2是进行三次采油的经济且有效手段;部署侧钻和加密井可精确挖潜剩余油.

In the fractured-vuggy reservoirs in the Tahe Oilfield, oil production declined rapidly due to strong heterogeneity, and the recovery rate was low. Based on the geologic and developing features of fractured-vuggy reservoirs, we proposed a new concept, which divided flow unit in single well, to predict residual oil. Residual oil usually enriched in the partially-filled sealing formations with poor physical property and weak energy, the wings of water-flooded area, the regional higher position, low-efficiency oil-replacing area in reservoir after water-flooding, corner area in water-flooding, and the poorly-connected area among different flow units in single well. In the wells with decreasing fluid-supplying ability and energy, water-flooding and controllable massive cracking were still effective ways in residual oil exploration. For those wells failed in water-flooding, drainage recovery and hydraulic dilatancy were recommended. N2 and CO2 injections were economic and effective ways for EOR. Side-tracking and infill well could be deployed to extract residual oil accurately.

https://doi.org/10.11781/sysydz2014S1056