裂缝诱导的TTI介质固液解耦反射系数方程及裂缝和流体参数反演方法  

Fracture-induced fluid-matrix decoupled reflection coefficient equation for TTI media and inversion method for fracture and fluid parameters

作　　者：严彬 张广智[1,2,3] 李林 杨睿[1,2] 朱振宇 李超[4] YAN Bin;ZHANG GuangZhi;LI Lin;YANG Rui;ZHU ZhenYu;LI Chao(Key Laboratory of Deep Oil and Gas,China University of Petroleum(East China),Qingdao 266580,China;China University of Petroleum(East China),Qingdao 266580,China;CNPC Key Lab of Geophysical Exploration,Beijing 102249,China;CNOOC Research Institute,Beijing 100028,China)

机构地区：[1]中国石油大学(华东)深层油气重点实验室,青岛266580 [2]中国石油大学(华东)地球科学与技术学院,青岛266580 [3]CNPC物探重点实验室,北京102249 [4]中海油研究总院有限责任公司,北京100028

出　　处：《地球物理学报》2023年第10期4349-4369,共21页Chinese Journal of Geophysics

基　　金：国家自然科学基金项目(U19B2008,U19B6003,42074136,41674130);国家科技重大专项(2016ZX05027004-001);中国石油前瞻性基础性项目(2021DJ0606)联合资助。

摘　　要：利用地震数据进行裂缝预测及流体识别对于裂缝性储层的勘探开发具有重要意义.针对单组旋转对称的倾斜裂缝诱导的TTI介质,基于各向异性Gassmann方程,推导了固液解耦纵波反射系数近似公式,分析了不同条件下近似公式的精度.根据实际研究工区裂缝储层的特征,选用高裂缝倾角近似公式,通过奇异值分解从方位弹性阻抗中估算裂缝密度和裂缝方位,进而分离和消除各向异性项,建立流体等效体积模量及孔隙度贝叶斯反演预测方法.模型试算表明,在信噪比大于2时,流体等效体积模量、孔隙度和裂缝参数的估计较为可靠,实际应用也验证了反演方法的有效性.Fracture prediction and fluid identification from seismic data are of great significance to the exploration and development of fractured reservoirs.Based on the anisotropic Gassmann model,a linearized fluid-matrix decoupled reflection coefficient equation for the Titled Transversely Isotropy(TTI)media induced by a single set of titled fracture was proposed.The accuracy of our approximate equation under different conditions was analyzed in detail.Then,according to the characteristics of the fractured reservoir in the field area,we employed a high-fracture-inclination approximate reflection coefficient equation to estimate fracture density and orientation from the azimuthal elastic impedance through a singular value decomposition.Further,a novel Bayesian EIVO inversion method was developed to estimate the effective fluid bulk modulus and porosity estimates by separating and eliminating the anisotropy term.Model test shows that our method can provide a reliably inverted result for the effective fluid bulk modulus,porosity and fracture parameters even with moderate noise.Field data test proves the effectiveness of our inversion method.

关 键 词：TTI介质 固液解耦近似 流体等效体积模量 裂缝参数 流体识别 

分 类 号：P631[天文地球—地质矿产勘探]