Artículos de revistas
Anisotropic complex Padeacute hybrid finite-difference depth migration
Registro en:
Geophysics. Soc Exploration Geophysicists, v. 75, n. 2, n. S51, n. S59, 2010.
0016-8033
WOS:000276868100024
10.1190/1.3337317
Autor
Amazonas, D
Aleixo, R
Schleicher, J
Costa, JC
Institución
Resumen
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Standard real-valued finite-difference (FD) and Fourier finite-difference (FFD) migrations cannot handle evanescent waves correctly, which can lead to numerical instabilities in the presence of strong velocity variations. A possible solution to these problems is the complex Padeacute approximation, which avoids problems with evanescent waves by rotating the branch cut of the complex square root. We have applied this approximation to the acoustic wave equation for vertical transversely isotropic media to derive more stable FD and hybrid FD/FFD migrations for such media. Our analysis of the dispersion relation of the new method indicates that it should provide more stable migration results with fewer artifacts and higher accuracy at steep dips. Our studies lead to the conclusion that the rotation angle of the branch cut that should yield the most stable image is 60 degrees for FD migration, as confirmed by numerical impulse responses and work with synthetic data. 75 2 S51 S59 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Petrobras Wave Inversion Technology (WIT) Consortium Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) FAPESP [06/04410-5]