Shear-wave propagation in anisotropic fractured/cracked media can provide valuable information about fracture swarm orientations. The main goal of this work is to recover information about fracture orientation based on the S-waveforms. For this study, ultrasonic measurements of S-waves in a synthetic physical model made of resin epoxy (isotropic matrix) with small rubber strips (artificial cracks) inserted in it to simulate a homogeneous anisotropic media. In this approach, it is used low, intermediate and high frequency shear-wave sources, with 90, 431 and 840 kHz, respectively. Integrating the S-wave seismograms, cross-correlation panels and the anisotropic parameter curves analysis, it was possible to estimate crack orientation in single fracture zones. Additional information was obtained from the high frequency peaks associated to scattered S-waves. This was possible using results from frequency versus angle of polarization curves. Moreover, a bandpass filtering process was performed in the intermediate and high frequencies seismograms in order to obtain low frequency seismograms. Spectral analysis from frequency-wavenumber (F-K) spectra was performed to support this filtering process. The results obtained using cross-correlation and parameter ᵞ from filtered data were quite similar to those obtained using low frequency source. This highlighted the possibility of using cheap high frequency sources to recover signals at low frequency range without losing traveltime information.
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