海拉尔深部南屯组高含泥储层压裂增产技术

FRACTURING STIMULATION TECHNOLOGY FOR HIGH SHALE-CONTENT RESERVOIRS IN EOWER ZUUNBAYAN FORMATION IN THE DEEP OF HAILAR BASIN

海拉尔盆地深部南屯组高含泥储层埋深大、岩石类型多、岩性复杂、泥质含量高、砂泥互层严重，导致压裂施工中闭合压力梯度高、近井裂缝形态复杂、近井摩阻大、施工压力高。因此，处理近井裂缝形态、降低压裂液滤失、抑制黏土膨胀、降低施工摩阻和压力是南屯组施工成功的关键。通过分析南屯组施工难点，形成了与之相适应的技术对策，研发了延缓交联低摩阻压裂液配方体系，并形成了针对性的压裂现场诊断和控制措施。现场应用153口井，施工成功率达94．8％，压裂后初期平均单井产液10．36m3／d、平均产液强度0．98m。／（m·d），平均单井产油5．72L／d、平均产油强度0．46t／（m·d），施工效果良好。该技术可为今后海拉尔盆地勘探开发提供重要的技术保障。

The high shale-content reservoirs in Lower Zuunbayan Formation in the deep of Hailar Basin are charac- terized by large buried depth, many rock types, complex lithology, high shalecontent and many sand-shale inter- beds, which leads to high-closure pressure gradient, complex near-wellbore fracture morphology, big near-wellbore friction resistance and high operation pressure during fracturing operations. Therefore, how to handle the near-well- bore fracture morphology, reduce the filtration of fracturing liquid, repress the clay swelling and reduce the friction resistance and pressure of operation have become the key of the operation success in Lower Zuunbayan Formation. Though the analyses of operation difficulties of Lower Zuunbayan Formation, the suitably technical countermeasures are proposed, and a fracturing liquid formula system of delaying cross-link and having low-friction resistance is developed. Moreover, the on-site diagnosis and control measures for fracturing operation are formed. There are 153 wells in field application, and the success rate is 94. 8%. The average liquid production rate per well at early stage after fracturing is 10. 36 m3/d, the average liquid production intensity is 0. 98 m3/ （ m . d） , the average oil production rate per well is 5.72 t/d, the average oil production intensity is 0. 46 t/ （ m . d } , and a good operation effect is obtained. This technique can provide an importantly technical guarantee for the future exploration and development of Hailar Basin.