基于叠前弹性参数的剩余油描述方法及应用

Method and application of residual oil description based on pre-stack elastic parameters

中后期老油田开发如何精准描述剩余油在井间的分布成为亟待解决的难题。文章基于长垣油田典型区块,利用其高密度地震资料,开展基于叠前弹性参数反演的剩余油预测应用技术研究。建立了密度、体积模量和剪切模量等弹性参数与含油饱和度的关系,采用Zeoppritz公式为核心的弹性参数反演算法,得到了密度、体积模量和剪切模量等弹性参数,实现了L1井区含油饱和度分布预测。经由后验井验证,含油饱和度描述准确率达75%以上。剩余油整体分布相对零散,呈“甜豆”状分布,在河道相砂体边部含油饱和度较高,指导措施调整后取得了较好的挖潜效果。

Accurately describing the distribution of remaining oil between drilling wells is very difficult in the middle and late stage of the development of oil fields.Based on the high density seismic data of typical blocks in Changyuan oilfield,the technology of remaining oil prediction based on pre-stack elastic parameter inversion is used so as to solve this intractable and urgent problem.Firstly,the relationship between the elastic parameters of density,volume modulus and shear modulus and oil saturation is established.Secondly,the elastic parameters of density,volume modulus and shear modulus are obtained by using the Zeoppritz formula as the core of the elastic parameter inversion algorithm,which lead to the realization of the prediction of oil saturation distribution in Well L1 area.After drilling well verification,the accuracy of oil saturation description is more than 75%.However,the overall distribution of the remaining oil is relatively scattered and shows a“sweet bean”distribution,with high oil saturation in the edge of the channel sand body.After the adjustment of guiding measures,a good potential tapping effect is achieved.