粘弹频变固液解耦流体因子地震反演方法研究及应用  

Research and Application of Seismic Inversion Methodfor Solid-Liquid Decoupling Fluid Factor Based onFrequency Variation Theory of Viscoelastic Media

作　　者：王振涛[1] 曲志鹏[1] 慎国强[1] WANG Zhentao;QU Zhipeng;SHEN Guoqiang(Geophysical Research Institute of Shengli Branch Company,Dongying 257022,China)

机构地区：[1]胜利油田分公司物探研究院,山东东营257022

出　　处：《CT理论与应用研究（中英文）》2024年第5期541-550,共10页Computerized Tomography Theory and Applications

基　　金：国家重点研发计划项目(重点含盐盆地钾盐成矿规律、勘查技术与增储示范(2023YFC2906500))。

摘　　要：地震波在含油气储层中传播时,因为波致流的影响,会发生振幅衰减与弹性参数频散现象,使得地震流体预测描述成为可能。但是,这些现象产生理论不明确和数学表达精度不高,使得含油气识别困难。为此,本研究首先根据地震振幅衰减与弹性参数频散现象,利用Chapman孔裂隙衰减理论考虑波致流影响,引入挤喷流效应,构建粘弹介质固液解耦流体因子。然后,推导构建关于流体因子的反射系数特征方程,并与Zoeppritz方程和Aki近似方程对比分析,验证新方程的精度。最后,基于叠前地震数据的分角度、分频带变化信息,提出粘弹频变固液解耦流体因子反演方法,并利用该流体因子在胜利油田胜北地区进行储层含油气性预测。研究结果表明,新构建的粘弹频变固液解耦流体因子对储层油气具有较强的敏感性,提出的地震反射特征方程和反演方法准确可靠,实际储层流体预测结果与测井解释结果吻合度较高,为复杂储层流体识别提供新的思路和方法。Propagation of seismic waves through oil/gas bearing reservoirs will be affected by wave-induced flow,resulting inamplitude attenuation and elastic characteristic dispersion,and making it possible to predict the presence of fluids.However,existing theories are unclear and mathematical expressions lack accuracy,making it difficult to predict the presence of oil andgas.This study examines the attenuation of seismic amplitude and the dispersion of elastic parameters,and uses Chapman'spore-crack attenuation theory,while considering the squirt flow effect,to construct a solid-liquid decoupling fluid factor.Subsequently,the reflection coefficient characteristic equation is constructed by using the new fluid factor,and compared withthe Zoeppritz and Aki approximation equations to demonstrate the improved accuracy of the new equation.Finally,a reservoirhydrocarbon-prediction method based on a pre-stack seismic inversion method using solid-liquid decoupling fluid factor isproposed.The reservoir fluid prediction is tested by using the inversion results of the new fluid factor to carry out reservoiroil/gas prediction in the well area A in the down-dropped block of Shengbei fault in China.The results show that the frequency-dependent viscoelastic solid-liquid decoupling fluid factor based on pre-stack seismic data is accurate and reliable,and theidentified reservoir fluid distribution results are in good agreement with logging interpretation results.This study providesnovel ideas and methods for fluid identification in complex reservoirs.

关 键 词：粘弹介质 波致流 频散和衰减 频变反演方法 储层流体预测 

分 类 号：P315[天文地球—地震学] P631[天文地球—固体地球物理学]