CAO ChengHao,
FU LiYun,
FU BoYe
.2020.An elastic numerical method based on the 3D complex medium Chinese Journal of Geophysics(in Chinese),63(7): 2836-2845,doi: 10.6038/cjg2020N0035
An elastic numerical method based on the 3D complex medium
CAO ChengHao1,3, FU LiYun2, FU BoYe1,3
1. Key Laboratory of Petroleum Resource Research, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China; 2. Key Laboratory of Deep Oil and Gas(China University of Petroleum(East China)), Qingdao 266580, China; 3. Institutions of Earth Science, Chinese Academy of Sciences, Beijing 100029, China
Abstract:Reservoir containing fractures exhibits the anisotropic characteristics. Thus the traditional effective medium theories assume an equivalence between the fractured sample and the transversely isotropic medium, however, which is not applicable for modeling and anisotropic analysis of complex fractured medium. Based on the previous studies, an effective numerical solution is developed, through a least squares procedure for the 3D complex medium containing cracks. We validate the accuracy of the numerical solution by the comparison with the traditional effective medium theories. The solution could not only avoid the parameter errors predicted by the Hudson and Eshelby-Cheng methods at the case of a larger crack density, but also take the crack interactions into account. Numerical study shows this solution can describe the anisotropic properties of the complex rock samples properly, thus provide appropriate seismic data for inversion of anisotropic parameters.
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