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| | Abstract | | The intrinsic component of attenuation is important in characterizing the physical properties of subsurface formations while positive utilization of seismic scattering to characterize fracture systems has been investigated. However, it is generally difficult to distinguish between intrinsic attenuation and scattering effects. Our numerical experiments demonstrate that the most popular method estimating scattering attenuation for field zero-offset VSP data by using synthetic data and isolating the intrinsic attenuation by subtracting the scattering attenuation from the total attenuation is not appropriate for separating intrinsic and scattering attenuation. Although most existing studies assume that the total attenuation is a summation of the intrinsic and scattering attenuation, the present study supports the existing knowledge that this assumption holds for the limit of extreme scattering in which the entire seismic energy propagation satisfies the diffusion equation. To overcome this limitation, we proposed a novel method for separating intrinsic and scattering attenuation for zero-offset VSP data by slightly modifying the MMFS (modified median frequency shift) method. We investigate the advantages of the proposed method by applying the proposed method to synthetic data. Finally, we preliminarily apply the proposed methods to field zero-offset VSP data and demonstrated the applicability of the proposed method. |
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