Reconstruction of Lame moduli and density at the boundary enabling directional elastic wavefield decomposition

Maarten V. de Hoop; Gen Nakamura; Jian Zhai

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arXiv · 1505.06960

Reconstruction of Lame moduli and density at the boundary enabling directional elastic wavefield decomposition

Maarten V. de Hoop·Gen Nakamura·Jian Zhai

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Abstract

We consider the inverse boundary value problem for the system of equations describing elastic waves in isotropic media on a bounded domain in $\mathbb{R}^3$ via a finite-time Laplace transform. The data is the dynamical Dirichlet-to-Neumann map. More precisely, using the full symbol of the transformed Dirichlet-to-Neumann map viewed as a semiclassical pseudodifferential operator, we give an explicit reconstruction of both Lam\'{e} parameters and the density, as well as their derivatives, at the boundary. We also show how this boundary reconstruction leads to a decomposition of incoming and outgoing waves.

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Maarten V. de Hoop, Gen Nakamura, Jian Zhai. 2015-05-26. Reconstruction of Lame moduli and density at the boundary enabling directional elastic wavefield decomposition. https://arxiv.org/abs/1505.06960

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