半空间反射弹性波多参数线性化逆散射

研究了BORN近似条件下的半空间中弹性波方程的多参数反演问题.采用宽带点源表面激发和接收扫描方案,建立了一个同时重构介质密度和拉梅参数的反演方法,证明了表面垂直和水平脉冲激发的散射场可以分解成P→P波、P→S波、S→P波及S→S波4类散射成分,其中包含着重建目标体参数分布所需的信息,所得到的参数重建显示表达式具有滤波反传播的形式.

Linearized Inverse Scattering for Elastic Parameters in a Half-Space With Reflection Date

The multi-parameter inversion of elastic wave equation in a half-space within the Born approximation is studied. A method of simultaneously reconstructing the configurations of the density and Lam parameters of the medium was presented by use of a wideband measuring schemes in which transmitters and receivers scan over the half-space surface. It is shown that the reflected waves generated by horizontal and vertical pulses on the surface can be decomposed into P→P、P→S、S→P and S→S types of scattering components. As is expected, these components contain enough information for desired restruction. From them the density and two Lam parameters are determined explicitly, and the results obtained have the form of filtered back-propagation as in the acoustic diffraction tomography.