川西白马庙蓬莱镇组低渗气藏的开发

THE DEVELOPMENT OF LOW-PERMEABILITY GAS RESERVOIRS OF PENGLAIZHEN GROUP IN BAIMAMIAO OF WEST SICHUAN

川西白马庙蓬莱镇组气藏砂体连续性差、储层非均质性强、含水饱和度高、单井产能低递减快,效益开发难度较大。近年来,对川西白马庙蓬莱镇组气藏开发实践表明,精细储层描述、精选开发层位井位是气藏开发的基础,新技术、新工艺和正确的开发技术和策略是气藏有效开发的保障。应用高分辨率层序地层学原理,建立储层各级别的等时地层格架,结合地质、测井和地震,确定不同的沉积微相组合;利用测井、测试、地震相干数据切片,对小层的砂体展布和沉积微相进行描述和标定,建立高产富集区分布模式;应用多井约束、多井标定、逐井外推的方法,优选开发层位和井位,确保钻井成功率。通过滚动开发逐步认识储层,降低风险,采用多层合采、水平井、分支井、大斜度井、加砂压裂等提高单井产能的措施,利用欠平衡钻井、空气钻井、射孔压裂联作来降低储层污染,确保致密低渗气藏的有效开发。

Baimamiao Penglaizhen Group gas reservoir in West Sichuan Basin is characterized by bad continuity of sandstone body, strong heterogeneity, high water saturation, quick depletion, and difficult to achieve economic development. Production practices in recent years indicate that refined reservoir description, and accurate identification for production layers and well locations are the base for gas development, on the other hand, new technology, new process, and proper application of development technology and strategy are the guarantee to efficient production. By adopting high-resolution sequence stratigraphy theory, different level isochronous stratum trellis of reservoir is established and in conjunction with geological, well logging, and seismic data, various combinations of deposit micro-facies are identified. Thin layer sandstone extension and deposit micro-facies are described and calibrated based on well logging, testing, and seismic data and gas enrichment zone distribution pattern is established. The method of multi-well restriction, multi-well calibration and well-by-well extrapolation is used to optimize production layer and well location to ensure drilling success. It is intended to deepen the knowledge of the reservoir and reduce development risks through scrolling development, to ensure effective development of tight low-permeability reservoir by the means of adopting stimulation measures such as multi-layer combined production, horizontal well, lateral well, high-angle well, and sand fracturing to increase single well productivity, and using under-balance drilling, air drilling, and combined operation of perforation and fracturing to lower reservoir contamination.