基于地震正演的低渗油藏甜点预测方法及应用——以渤海B油田为例

Sweet spot prediction method of low permeability reservoir based on seismic forward modeling and its application:a case study of B oilfield in Bohai sea

低渗储层成因及控制因素多样,相对高渗储层(甜点)分布规律复杂,储层非均质性强,预测难度大。常规的地球物理方法可以有效区分岩性,但对低渗储层中的甜点区并不能很好地进行甄别。这里以海上某辫状河三角洲沉积低渗油田为例,通过总结低渗油藏储层高低渗分布模式特点,在此基础上建立相应的机理模型,研究低渗储层中相对高渗条带的地震正演响应特征规律,并以此为基础进行敏感地震属性优选,最终开展相约束的两步法预测相对高渗条带分布规律,为油田开发井部署提供借鉴。

Due to the various genesis and control factors,the low permeability reservoir has strong heterogeneity.The distribution law of the relatively high permeability reservoir(sweet spot)is complex,which is difficult to be predicted.Conventional geophysical methods can effectively distinguish lithology,but the sweet spot in the low permeability reservoir cannot be well discriminated.This paper,taking a braided river delta sedimentary oilfield as an example,summarizes the distribution patterns of high and low permeability reservoir characteristics of low permeability reservoirs.And then the mechanism of the mathematical model is set up on the basis of this.The relatively high permeability belts in low permeability reservoir seismic forward modeling is studied,and then sensitive seismic attributes are selected.Finally,the relative high permeability belts distribution is predicted based on a two-step seismic facies constrained method.The final results can provide powerful basis for oilfield development well deployment.