Kirchhoff prestack depth scalar migration of complete wave fields in simple inhomogeneous weakly anisotropic velocity models: PP, PS1 and PS2 waves

Vaclav Bucha

Summary

We use the 3-D ray-based Kirchhoff prestack depth scalar migration to calculate migrated sections in two simple inhomogeneous weakly anisotropic velocity models. Each velocity model is composed of two layers separated by a curved interface. The upper layer is inhomogeneous weakly anisotropic and the bottom layer is isotropic. The "recorded" complete seismic wave fields are calculated using the Fourier pseudospectral method. We apply the 3-D Kirchhoff prestack depth scalar migration to a single-layer velocity model with the same anisotropy as in the upper layer of the velocity model used to calculate the recorded wave field. We migrate the recorded wave field using three different ray-theory approximations of S waves: (a) common S-wave approximation of both S waves, (b) anisotropic-ray-theory approximation of S waves, (c) prevailing-frequency approximation of the coupling ray theory for S waves. We show and discuss the results of the migration of the complete wave field.

Keywords

Fourier pseudospectral method, 3-D Kirchhoff prestack depth scalar migration, anisotropic velocity model, weak anisotropy, complete wave field, coupling ray theory

Whole paper (password required until June 2020)

The paper is available in PDF (9674 kB).


Seismic Waves in Complex 3-D Structures, 29 (2019), 19-38 (ISSN 2336-3827, online at http://sw3d.cz).