Importance of phase guides from beamformed data for processing multi-channel data in highly scattering media

Abstract

Small- and medium-scale scattering can be extremely damaging for acoustic imaging. The mechanism for distortions is related to severe frequency-dependent phase perturbations making signals obscure on multi-channel records. Methods are proposed to compensate for such effects in seismic reflection imaging in two steps. First, the rough signal guide is constructed using massive beamforming. Second, trace-by-trace specialized time-frequency masking is employed to reconstruct the corrupted phase and amplitude spectra. Phase masks are of paramount importance to make target events coherent and visible. Amplitude masks remove scattered background noise from the amplitude spectra. Unlike beamforming itself, these methods avoid smearing of signals across channels and preserve full frequency bandwidth.