论文部分内容阅读
根据Biot理论和均匀性理论分析了流体饱和孔隙介质中波的传播,可计算低速层介质中地震导波的散射和衰减。根据本构关系,平衡方程和改进Biot理论后的广义Darcy定律,可求出各种方程的耦合系统,其中的每个方程都控制着每层中波的运动。位移场和应力场都满足界面上引力和位移连续性边界条件和无限远点散射的条件。为避免单个矩阵中大波数呈指数增长时出现的精度问题,我们采用全局矩阵法代替常规传播法来估计散射和衰减的关系。这一研究结果表明,导波的衰减对于目的层渗透性是灵敏的,尤其是当低速层的渗透性在群速度最小Airy相位处变化时,衰减的变化很大。
According to the theory of Biot and the theory of uniformity, the wave propagation in fluid saturated porous media is analyzed, and the scattering and attenuation of the guided wave in low velocity media can be calculated. According to the constitutive equation, the equilibrium equation and the generalized Darcy’s law after the improved Biot theory, we can find the coupling system of various equations, each of which controls the movement of the wave in each layer. Both the displacement field and the stress field satisfy the boundary conditions of gravity and displacement continuity and the scattering at infinity in the interface. In order to avoid the problem of accuracy in the exponential growth of large wave numbers in a single matrix, we use the global matrix instead of the conventional propagation method to estimate the relationship between scattering and attenuation. The results of this study show that the attenuation of the guided wave is sensitive to the permeability of the target layer, especially when the permeability of the low velocity layer changes at the lowest Airy phase of the group velocity.