We make inferences about the physical properties of heterogeneous media from scattered (elastic) waves. Indoors, these waves are mostly ultrasonic, excited and detected with lasers. Outside, probing waves are in the seismic frequency band.

Apple Seismology; for more info visit the publications page.

As our wavelengths span orders of magnitudes, so do our applications. Outside, targets include the Auckland Volcanic Field, geothermal exploration, and micro-seismicity for fluid reservoir characterization. In the laboratory, we do rock physics in collaboration with the PORO lab, ice physics, medical imaging.


  • Ultrasonic imaging of blood flow in human bone
    A new publication hit the press this week on ultrasonic imaging of bone in Journal of Bone and Mineral Research PLUS.   For the first time, we demonstrated quantitative measurements of blood flow in the cortical bone layer of a cohort of human volunteers. This paper is a continuation of Jami Shepherd's postdoctoral research in the…
  • Alpine Fault rocks going non-linear
    A new publication led by Jonathan Simpson appeared in Geophysical Research Letters, this month.  Laser ultrasonic measurements show that the wave speed in Alpine Fault rocks decreases for waves with a larger amplitude, as shown below. The closer to the fault, the more the wave speed decreases with amplitude. The observation of "rock weakening" contributes…
  • Jonathan Simpson wins student award at the AGU meeting
    In December 2020, the AGU meeting was held virtually, and Jonathan won a best student presentation in the seismology section of the meeting with a presentation that blended a traditional "zoom-style" presentation with a tour of the setup of his laser-ultrasound experiments on nonlinear rock properties under in situ conditions. These nonlinear rock properties may…

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