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arXiv · 1906.07474

3D Prestack Fourier Mixed-Domain (FMD) depth migration for VTI media with large lateral contrasts

Hao Zhao·Leiv J. Gelius·Martin Tygel·Espen Harris Nilsen·Andreas Kjelsrud Evensen
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Abstract

Although many 3D One-Way Wave-equation Migration (OWEM) methods exist for VTI media, most of them struggle either with the stability, the anisotropic noise or the computational cost. In this paper we present a new method based on a mixed space- and wavenumber-propagator that overcome these issues very effectively as demonstrated by the examples. The pioneering methods of phase-shift (PS) and Stolt migration in the frequency-wavenumber domain designed for laterally homogeneous media have been followed by several extensions for laterally inhomogeneous media. Referred many times to as phase-screen or generalized phase-screen methods, such extensions include as main examples of the Split-step Fourier (SSF) and the phase-shift plus interpolation (PSPI). To further refine such phase-screen techniques, we introduce a higher-order extension to SSF valid for a 3D VTI medium with large lateral contrasts in vertical velocity and anisotropy parameters. The method is denoted Fourier Mixed-Domain (FMD) prestack depth migration and can be regarded as a stable explicit algorithm. The FMD technique was tested using the 3D SEG/EAGE salt model and the 2D anisotropic Hess model with good results. Finally, FMD was applied with success to a 3D field data set from the Barents Sea including anisotropy.

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BibTeXRIS

Hao Zhao, Leiv J. Gelius, Martin Tygel, Espen Harris Nilsen, Andreas Kjelsrud Evensen. 2019-06-18. 3D Prestack Fourier Mixed-Domain (FMD) depth migration for VTI media with large lateral contrasts. https://doi.org/10.1016/j.jappgeo.2019.06.009

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