资阳须五段高密度体积压裂技术优化

Optimization of high-density volume fracturing technology for Xuwu member in Ziyang

四川盆地资阳须五段致密砂岩气藏具有储层非均质性强,改造体积不高、压裂适应性较差的特点,主要表现在加砂规模较小(20~60 m^(3)),施工压力较高(50~82 MPa),压裂后产量不理想。基于裂缝扩展模型进行地质工程一体化分段分簇实现高密度完井,以大排量造缝携砂理念优化支撑剂铺置,配套双重暂堵转向工艺实现多簇裂缝的均匀扩展,提高裂缝对砂体的控制程度。结果表明,11.8条/100 m高密度布缝能有效提高储层平面动用程度,以2.73 m^(3)/m高强度粒径组合铺置能构建高导流人工裂缝,运用“缝口+缝内”双重暂堵转向工艺可有效提高分簇有效性。该工艺现场应用后加砂规模提高到2000~3000 m^(3),综合砂液比提高到17.6%,横向覆盖率提高至91%,已实施井体积改造测试产量为邻井常规压裂的6~10倍,DF501HF井计算无阻流量46.5×10^(4)m^(3)/d,EUR 0.78×10^(8)m^(3),增产效果明显,为深层须家河组气藏开发提供技术储备。

The tight sandstone gas reservoir in Xujiahe formation in Ziyang,Sichuan Basin,is characterized by strong heterogeneity,low transformation volume,and poor fracturing adaptability,leading to relatively small overall sand injection volume(20~60 m^(3))and high construction pressure(50~82 MPa),resulting in unsatisfactory post-fracturing production.To address these challenges,a geological engineering integrated segmentation and clustering approach based on a fracture expansion model was employed to achieve high-density well completion.The proppant distribution was optimized with the concept of large-displacement proppant placement,and the uniform expansion of multiple fracture clusters was achieved with a dual temporary plugging and reorientation technique,which improve the control of cracks on sand bodies.The results show that a high-density distribution of 11.8 fractures per 100 meters effectively improved the reservoir′s areal drainage efficiency.The placement of high-strength,large-sized proppant with a volume of 2.73 m^(3)/m helped build high-conductivity artificial fractures,and the application of the"fracture-mouth+within-fracture"dual temporary plugging and reorientation technique significantly enhanced the effectiveness of clustering.The sand injection volume was increased to 2000~3000 m^(3),and the overall sand-fluid ratio was raised to 17.6%,with lateral coverage reaching 91%after the on-site application of this process.The testing production of wells implemented with volume transformation was 6~10 times higher than that of neighboring wells with conventional fracturing.For Well DF501HF,the calculated open flow rate is 46.5×10^(4)m^(3)/d,and the EUR is 0.78×10^(8)m^(3),showing significant production enhancement effect,with may provide a valuable technical reserve for the development of the gas reservoir in deep Xujiahe formation.