LAUSR

ABSTRACTAlthough attenuation estimation methods using sonic logging waveforms provide the highest resolution among seismic methods and enable us to characterize in great detail the attenuation properties of subsurface rocks, such attenuation estimation methods are not used routinely, indicating that there is still room for improvement. To further improve the performance of an existing modified median frequency shift (MMFS) method, we have developed a new algorithm by combining seismic interferometry (SI) and the common-midpoint (CMP) approach. Redatuming a transmitter position by applying SI can shorten the transmitter-receiver distance, leading not only to higher depth resolution but also to a lower signal-to-noise ratio (S/N) of the attenuation profiles. To compensate for the decrease in the S/N, we used the redundancy of overlapping receivers at each receiver level in a sonic logging measurement using the multireceiver tool; we improved the S/N by stacking the redatumed sonic logging waveforms. Then, b...