Extracting high-resolution, multi-mode surface wave dispersion data from distributed acoustic sensing measurements using the multichannel analysis of surface waves

We rigorously assess the potential for extracting high-resolution, multi-mode surface wave dispersion data from distributed acoustic sensing (DAS) measurements using active-source multichannel analysis of waves (MASW). have utilized both highly-controlled, broadband vibroseis shaker trucks and more-variable, narrow-band sledgehammer sources to excite near surface, compare DAS-derived obtained source types directly with concurrently acquired traditional geophone-derived data. find that differences between two approaches are minimal well within uncertainty bounds associated each individual measurement type when following conditions met DAS: (a) a tight-buffered or strain-sensing fiber-optic cable is used, (b) buried in shallow trench enhance coupling, (c) short gauge lengths small channel separations used. also show frequency-dependent normalization image MASW processing removes effects scaling, integration, differentiation on measured waveforms, thereby allowing nearly identical be extracted geophone waveforms DAS without requiring them first converted into equivalent units. demonstrate wavelength limited by length more commonly considered separation. further it possible extract essentially seismic made array different cables. Finally, we shear velocity profiles recovered an uncertainty-consistent, inversion agree favorably cone penetration tests performed at site.