期刊
FRONTIERS IN EARTH SCIENCE
卷 10, 期 -, 页码 -出版社
FRONTIERS MEDIA SA
DOI: 10.3389/feart.2022.1031490
关键词
acoustoelasticity; finite difference; wave propagation; prestress; decoupling
Seismic exploration of deep oil/gas reservoirs requires considering wave propagation in high-pressure media, as well as nonlinear strain responses due to finite stresses. Decoupling the elastic waves from high-pressure deep formations is crucial for further development in prospecting technology. This study presents a decoupling method using acoustoelasticity equations and a finite-difference method, demonstrating the significant impact of prestressed conditions on seismic responses.
Seismic exploration of deep oil/gas reservoirs involves wave propagation in high-pressure media. Acoustoelasticity with the third-order elastic constants can account for nonlinear strain responses due to stresses of finite magnitude. Since current seismic exploration depends primarily on P waves, further development in prospecting technology to handle deep reflection data will benefit from the ability to decouple the elastic waves from high-pressure deep formations. We decouple the first-order velocity-stress acoustoelasticity equations for wave propagation under isotropic (confining) and anisotropic (uniaxial and pure shear) prestress conditions. A rotated staggered-grid finite-difference (RSG-FD) method is used to solve the decoupled acoustoelasticity equations with an unsplit convolutional perfectly matched layer (CPML) absorbing boundary. Numerical examples demonstrate the significant impact of prestressed conditions on seismic responses in both phase and amplitude. The stress-induced seismic anisotropy with orthotropic characteristics is strongly related to the orientation of prestresses. We compare the coupled and the decoupled wavefields to validate the proposed decoupling method. Investigation of the influence of prestresses on the acoustoelastic decoupling illustrates that the isotropic prestress does not affect the decoupling, but the anisotropic prestresses significantly affect the decoupling accuracy.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据