Near-Surface 2D Imaging via FWI of DAS Data: An Examination on the Impacts of FWI Starting Model

Full waveform inversion (FWI) and distributed acoustic sensing (DAS) are powerful tools with potential to improve how seismic site characterization is performed. FWI able provide true 2D or 3D images of the subsurface by inverting stress wave recordings collected over a wide variety scales. DAS can be used efficiently collect high-resolution from long complex fiber optic arrays well-suited for large-scale projects. Due relative novelty combining DAS, there presently little published literature regarding application data near-surface (depths < 30 m) characterization. We perform on at well-characterized using four different, site-specific 1D starting models. discuss unique benefits challenges associated compared traditional geophone data. examine impacts various models final images. demonstrate that while inversions performed all fit major features waveforms similar misfit values, quite different one another depths greater than about 10 m. As such, best representation(s) evaluated based on: (1) their agreement borehole lithology logs were not in development models, (2) consistency shallow between inverted derived multiple Our results applied has significant as tool also emphasizing impact model selection have results.