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Physical modeling, using ultrasonic sources and receivers over scaled exploration structures, plays a useful role in wave propagation and elastic property investigations. This paper explores the anisotropic response of novel fractured glass blocks created with a laser-etching technique. We compare transmitted and reflected signals for P-and Swaves from fractured and unfractured zones in a suite of ultrasonic experiments. The unaltered glass velocities are 5801 m/s and 3448 m/s for P and S waves, respectively, with fractured zones showing a small decrease (about 1%). Signals propagating through the fractured zone have decreased amplitudes and increased coda signatures. Reflection surveys (zero-offset and variable polarization and offset gathers) record significant scatter from the fractured zones. The glass specimens with laser-etched fractures display a rich anisotropic response.

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Many regions of subsurface interest are, or will be, fractured. Seismically characterizing these zones is a complicated but essential task for resource development. Physical modeling, using ultrasonic sources and receivers over scaled exploration targets, can play a useful role as an analog for reservoir imaging and assessment. We explored the anisotropic response of glass blocks containing internal fractures created by a novel laser-etching technique. We compared transmitted and reflected signals for P- and S-waves from fractured and unfractured zones in a suite of ultrasonic (1–5 MHz) experiments. The unaltered glass velocities have averages of [Formula: see text] and [Formula: see text] for P- and S-waves, respectively (giving [Formula: see text]). The unfractured glass has a very high quality (Q) factor of over 500 for P-waves and S-waves. The fractured zones have a small (up to 1.5%) velocity decrease. Signals propagating through the fractured zone have diminished amplitudes and increased coda signatures. Reflection surveys (zero-offset and with variable polarizations) record significant scatter from the fractured zones. The fracture-scattered energy can be migrated to provide a sharper image. The glass specimens with laser-etched fractures display a rich anisotropic response, which can help inform field-scale imaging.