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| A preconditioning scheme for full waveform inversion | |
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Abstract:
The waveform inversion problem is inherently ill-posed. Traditionally, regularization terms are used to address this issue.
For waveform inversion where the model is expected to have many details reflecting the physical properties of the Earth,
regularization and data fitting can work in opposite directions: the former smoothing and the later adding
details to the model. In this paper, we constrain the velocity model
with a model-space preconditioning scheme based on directional Laplacian filters. This preconditioning strategy preserves the
details of the velocity model while smoothing the solution along known geological dips. The Laplacian filters have the property to smooth
or kill local planar events according to a local dip field. By construction, these filters can be inverted and used in a preconditioned
waveform-inversion scheme to yield geologically meaningful models. We illustrate on a 2-D synthetic example how preconditioning
with non-stationary directional Laplacian filters outperforms traditional waveform inversion when sparse data are inverted for.
We think that preconditioning could benefit waveform inversion of real data where (for instance) irregular geometry, coherent noise and lack of low
frequencies are present.
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| A preconditioning scheme for full waveform inversion | |
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Next: Introduction
Up: Reproducible Documents
2010-11-26