缝洞型碳酸盐岩油藏“二次定量雕刻”技术及其应用

Aiming at the problems in the Ordovician fractured-vuggy carbonate reservoirs in the Tarim Basin, such as the well-developed pores, caves and fractures, extremely strong heterogeneity, large uncertainty in the result of a single carving relying on static seismic data, and difficulty in improving the quantitative carving accuracy of effective reservoirs, on the basis of a single static carving, fully considering many key influencing factors faced in the carving process, and combining static and dynamic data, a "secondary quantitative carving" technology for fractures and caves is proposed. This technology combines dynamic analysis and research means such as well test analysis, production instability analysis, dynamic reserve analysis, and dynamic connectivity evaluation. The understanding of reservoirs from dynamic analysis is used as statistical parameters to constrain seismic wave impedance inversion, improve the relationship model between wave impedance and porosity, determine the morphology of fracture-cave bodies, calculate dynamic reserves, and then optimize a more accurate fracture-cave model, and dynamically back-calculate the oil-water interface on the basis of the secondary carving results. This technology can greatly reduce the uncertainty of a single static carving of fracture-cave bodies, improve the accuracy of carving results, and has achieved good results in the development practice of fractured-vuggy carbonate reservoirs in the Tarim Basin.

针对塔里木盆地奥陶系缝洞型碳酸盐岩油藏孔洞缝发育、非均质性极强、依靠静态地震资料的一次雕刻结果不确定性大、提升有效储集体定量雕刻精度难的问题,在一次静态雕刻基础上,充分考虑雕刻过程中面临的诸多关键影响因素,动静结合,提出缝洞“二次定量雕刻”技术。该技术结合试井分析、产量不稳定分析、动态储量分析、动态连通性评价等动态分析与研究手段,将动态分析的储集层认识作为统计参数约束地震波阻抗反演、完善波阻抗与孔隙度关系模型,确定缝洞体形态,计算动态储量,进而优选更为准确的缝洞模型,并在二次雕刻结果的基础上动态反推油水界面。本技术可大大降低缝洞体静态一次雕刻的不确定性,提高雕刻结果的精度,并在塔里木盆地缝洞型碳酸盐岩油藏的开发实践中收到了良好的成效。