Analysis of an iterative deconvolution approach for estimating the source wavelet during waveform inversion of crosshole georadar data

Abstract

A major issue in the application of waveform inversion methods to crosshole georadar data is the accurate estimation of the source wavelet. Here, we explore the viability and robustness of incorporating this step into a time-domain waveform inversion procedure through an iterative deconvolution approach. Our results indicate that, at least in non-dispersive electrical environments, such an approach provides remarkably accurate and robust estimates of the source wavelet even in the presence of strong heterogeneity in both the dielectric permittivity and electrical conductivity. Our results also indicate that the proposed source wavelet estimation approach is relatively insensitive to ambient noise and to the phase characteristics of the starting wavelet. Finally, there appears to be little-to-no trade-off between the wavelet estimation and the tomographic imaging procedures. ► Crosshole georadar waveform inversion is a powerful subsurface imaging method. ► Accurate source wavelet estimation is a major issue for waveform inversion approaches. ► Iterative deconvolution approach provides accurate estimation of source wavelet. ► This wavelet approach remains viable and robust even under challenging conditions.