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Machine learning applications are gaining popularity in geophysical applications, as they are able to circumvent inverse problems through statistical relationships. Among others, Bayesian Evidential Learning (BEL) enables dynamic data integration and allows for uncertainty quantification. It relies on a simulation-based prior that through statistical relationships identifies the correlation between a given frame and an observed dataset in a computational non-demanding way.
In the work here presented, we apply BEL on the surface wave analysis problem, that is usually marked by subjective decision-making for dispersion curve and mode picking and depends on deterministic or stochastic inversion schemes. Interface seismic waves, such as Rayleigh, Love and Scholte waves, exhibit frequency-dependent phase velocities, i.e., dispersion, that can be used to image the near-surface. We use wavefield transform methods to identify surface wave dispersion from observed seismic shot gathers, that given a prior model space, can be directly used on the transform i.e., without dispersion curve extraction, to predict an ensemble of 1D near-surface profiles mapping selected parameters such as velocity, density or attenuation. Simultaneously, we are able to quantify the uncertainty of the solution ensemble as well as to detect if the considered wavefield transform falls outside of the defined prior.