【作者】 杨磊；

【导师】 杨顶辉；

【作者基本信息】 清华大学 ， 数学， 2014， 博士

【摘要】 储层介质的粘弹性性质、Biot流机制、喷射流机制和多相流是影响波频散与衰减的重要因素。研究这些机制耦合作用下的波频散和衰减对储层预测和油气开发具有重要的指导意义。首先给出了部分应力形式的BISQ模型，对其进行波场分解获得了P波和S波拉梅势所满足的偏微分方程，从而得到了高维BISQ模型低频近似公式。进一步地将特征喷射流长度进行修正以适应多相流并存情况，得到了含多相流BISQ模型及其低频近似公式，研究了含多相流储层介质中的波频散衰减规律。数值结果表明，在多种流体共存情况下，粘弹性强弱显著影响快P波和S波的频散和衰减，而对慢P波频散和衰减的影响较弱。渗透率对孔隙介质中快、慢P波的影响较为显著而对S波的影响较弱。气体含量变化影响快P波的频散和衰减以及S波的速度，而对慢P波几乎没有影响。其次给出了求解BISQ模型的SSM方法，该方法具有粗网格下，压制数值频散能力强、计算速度快的优点。利用SSM方法给出了多相流并存情况下的波场。结果表明，含多相流BISQ模型中快P波速度小于Biot模型中快P波速度；孔隙介质中快P波速度随含气的增加而变大。再次给出了Biot流机制、喷射流机制和多相流共同作用下P波和S波拉梅势在流-固分界面上所满足的偏微分方程，建立了反射和透射系数在流-固分界面上所满足的函数关系,研究了入射角、渗透率和多相流等因素对反射和透射的影响，发现了快P波的临界角随气体含量增加而减小。最后为了验证含多相流BISQ模型的有效性，将其与自适应杂交遗传算法相结合，给出了储层介质粘弹性、Biot流机制、喷射流机制和多相流耦合作用下的储层参数反演方法，并对理论合成数据、实验数据和野外观测数据进行了反演。结果表明，自适应杂交遗传算法计算速度快、反演精度高,是有效的储层参数反演方法，含多相流粘弹性BISQ模型能准确地描述低频情况下的波频散特征，使用含多相流BISQ模型的低频近似公式能够有效预测储层参数，并且显著提高反演计算速度。更多还原

【Abstract】 The Biot mechanism, Squirt-flow mechanism, viscoelasticity and multiphase floware the most important factors that affect the wave dispersion and attenuation. So it isvery import for the reservior prediction to study their influenc on the wave dispersionand attenuation.Fisrt, high dimensional BISQ model of the partial stress form is given, and thewave propagation equation that the P-wave and S-wave Lame potentials satisfy is givenby performing wave field decomposition on the BISQ model. Based on the Lamepotentials equation, the low frequency approciamtion formula is derived. Furthermorethe BISQ model containing multiphase flow is gained by correcting the charastic squirtlength and its low frequency approcimation formula is also derived to study the wavedispersion and attenuation. Numerical result shows that viscoelasticity affect both thedispersion and the attenuation of the fast P-wave and the S-wave, whereas affect littleon slow P-wave. Permbility affect fast P-wave and slow P-wave greatly but little on theS wave. Gas content in porous system affect greatly on dispersion and attenuation of thefast P-wave, the velocity of S-wave, and has almost no effect on the slow P-wave.Second, the SSM method is given for solving the BISQ model containingmultiphase flow. It eliminates the numerical dispersion effectively under coarse grids,and has quick computation speed. Wave field is simulated with multiphase flowincluded in the porous fluid, which reveals that the fast P wave velocity of the BISQmodel is slower than that of the Biot model, and becomes larger when gas contentincreases.Third, it is derived that the partial different equations which the the P-wave andS-wave Lame potential satisfies at the fluid-solid interface under the coupling action ofBiot mechanism, Squirt-flow mechanism and multiphase flow. Then the relationship ofthe reflection and transmission coefficients at the interface is gived to study theinfluence of incident angle, permeability and the gas content on the relection andrefraction. It is discovered that critical angle of the fast P-wave decreases with gascontent increasing.Finally, in order to verify the validity of the BISQ model containing multiphaseflow, it is applied to inverse synthetic, experimental and real data together with the self-adaptive hybrid genetic algorithm. Inversion results show the self-adaptive hybridgeneric algorithm is a effective method to inverse more accurate result very quickly, theviscoelastic BISQ model containing multiphase flow is effective to depict the dispersionand attenuation at the low frequency range, and the low frequency approcimationvelocity formula is effective to predict accurate reservoir parameter, and improve theconputation speed greatly.更多还原