高陡构造区枯竭型油气藏改建地下储气库配套地震解释技术序列

Seismic interpretation technology sequence supporting the rebuilding of underground gas storages(UGSs)from depleted oil and gas reservoirs in high-steep structure zones

由枯竭型油气藏改建的地下储气库(以下简称储气库)具有储气量大、投资相对较低等优点,是储气库建库的首选目标。高陡构造区由于构造复杂、储层厚度薄,准确落实地下构造真实形态和目标地层深度难度大,地质目标难以一次性中靶。为了形成一套有针对性的高陡构造区枯竭型油气藏改建储气库的地震解释技术序列,对整个建库期间使用到的地震解释技术进了梳理和分析。研究结果表明:①基于多井控制的地震地质综合解释技术可以对构造进行准确的三维空间雕刻,能够有效地解决高陡构造真实形态和目标地层深度预测的难题,进而对气藏的封闭性做出评价;②所形成的地震导向技术,为注采井的实施提供了强有力的物探技术支撑,有效地指导了注采井工艺的设计、实施,为提高高陡复杂构造区钻探成功率提供了可靠的资料,提高了钻井速度与效益;③随钻过程中实时跟踪调整,可以有效提高注采井一次性入靶率和目的层段的进尺。结论认为,所形成的配套地震解释技术序列为四川盆地东部XGS地下储气库建设提供了强有力的技术支撑,有效地指导了注采井工艺的设计实施以及动态调整井轨迹方案,提高了钻井一次性中靶率,大幅度提高了石炭系地层及储层的钻遇率,对今后枯竭型油气藏改建储气库工程具有参考借鉴意义。

An underground gas storage(UGS)rebuilt from depleted oil and gas reservoirs has the advantages of great gas storage capacity and lower investment,and it is the preferred target of gas storage construction.In high-steep structure zones,the structures are complicated and the reservoirs are thin,so it is difficult to accurately determine the real morphology of underground structures and the depth of target reservoirs and to hit the geological target in one time.In order to establish a set of seismic interpretation technology sequence specifically for rebuilding UGSs from depleted oil and gas reservoirs in high-steep structure zones,this paper sorts out and analyzes the seismic interpretation technologies used in the whole period of UGS building.And the following research results are obtained.First,the seismogeological comprehensive interpretation technology based on multi-well control can accurately depict structures in the 3D space and effectively solve the difficulties in the morphological reflection of high-steep structure and the depth prediction of target layer,so as to evaluate the sealing capacity of gas reservoir.Second,the seismic guidance technology provides powerful geophysical exploration technology support for the implementation of injection/production wells,effective guidance for the design and implementation of injection/production well process and reliable data for the drilling success ratio in high-steep complex structure zones,so as to improve drilling speed and benefit.Third,the real-time tracking and adjustment while drilling can effectively increase the one-time target hit ratio of injection/production wells and the drilling footage of target intervals.In conclusion,this support seismic interpretation technology sequence provides powerful technological support for the building of XGS UGS in the eastern Sichuan Basin,effectively guides the design and implementation of injection/production well process and the dynamic adjustment scheme of hole trajectory,improves the one-time target hit ratio and increases the drilling rate of Carboniferous and reservoirs greatly.It is of important reference and guidance significance to the future rebuilding engineering of underground UGSs from depleted oil and gas reservoirs.