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Proposed method

I propose a new method that balances the advantages and disadvantages of the conventional methods discussed in the above section. The basic idea of this proposed method is to use central frequency shift (Quan and Harris, 1997) to analyze Q versus offset (QVO) (Dasgupta and Clark, 1998) or Q versus angle (QVA) in the image domain.

According to equation 7, the central frequency shift varies with offset because of differing raypath geometries, and hence in accumulated attenuation. Specifically, if I define a central-frequency versus offset or versus angle domain, the central frequency is flat when there is no absorption, but shows a curvature in an absorptive medium. By the same reasoning, the same response can be observed in the central-wavenumber-versus-offset/angle domain, which can be obtained after migration.