构造建模约束地震反演技术——以大庆萨尔图油田南八区为例

Structure modeling-constrained seismic inversion technology——a case study from Nanba area in Saertu oilfield,Daqing

为了充分发挥储层预测多学科的综合能力,对构造建模约束地震反演的作用和构造建模在储层反演与地质建模的区别进行了分析。在此基础上,详细阐述了实现构造建模约束地震反演的4个关键环节,即井-震联合小尺度构造解释、合理设计地质框架、不同尺度网格设计和曲线均一化处理。以大庆萨尔图油田南八区萨Ⅱ7-12沉积单元为例,通过与未进行构造约束的地震反演对比,总结出构造建模约束下地震反演的优势,主要体现在:①能够提高砂体识别的准确程度,尤其是定位河道砂边界位置效果显著,采用"井点定相、切片组形"的方法,完成了井震结合沉积微相的修正;②明确主力厚油层及主力砂体接触关系,增加断层附近预测的细节,尤其是断裂两侧砂体明朗化,有利于指导剩余油的挖潜。因此,构造建模约束地震反演技术能够降低反演的不确定性,对油田后续开发调整具有重要意义。

This paper introduces structure modeling-constrained seismic inversion technique.It has four key components,i.e.well-seismic integrated small scale structure interpretation,rational design of geologic framework,multi-scale grid design and curve homogenization.Take SⅡ7-12 sedimentary units in Nanba area of Daqing Saertu oilfield as an example,the article summarizes the advantages of structure modeling-constrained seismic inversion over seismic inversion without structure modeling.①It can improve the accuracy of sandbody identification,especially channel sand and realize wellseismic integrated correction of sedimentary microfacies through ＂defining facies in wells and shapes on slices＂;②It can reveal the contact relationship between major thick reservoir and the main sand body,and refine the prediction of sandbodies near faults,so as to guide remaining oil potential tapping.It is concluded that structure modeling-constrained seismic inversion can lower the uncertainty of seismic inversion and is of great significance to oilfield development adjustment in later stage.