Gregory C. McLaskey earned his B.S., magna cum laude, in civil engineering from Cornell University and his master’s and Ph.D. degrees from the University of California, Berkeley, the latter in 2011. In grad school he was awarded a National Science Foundation Graduate Research Fellowship. He then spent 3 years at the U.S. Geological Survey (USGS) in Menlo Park on a Mendenhall Postdoctoral Fellowship. This fall he began a faculty position at Cornell in the School of Civil and Environmental Engineering.
Greg has derived new insights on earthquake physics through a series of innovative experimental studies. Using a direct shear apparatus that he designed and built, including transducers that are calibrated with Green’s functions for the experimental geometry, he found that laboratory-generated earthquakes with longer recurrence intervals generate more high-frequency energy (McLaskey et al., Nature, 2012). This relationship is also seen for small natural earthquakes and suggests that fault healing time plays a role in determining earthquake spectra.
In his postdoctoral work on the large-scale rock friction apparatus at the USGS in Menlo Park, Greg found that clusters of high-frequency foreshocks can occur in a slowly slipping patch of the experimental fault if the rate of applied local shear stress is high enough, suggesting that the transition between aseismic and seismic slip is modulated by the local stress field (McLaskey and Kilgore, Journal of Geophysical Research, 2013). Another striking result is that populations of tiny seismic events (magnitudes of −6 to −7) have stress drops that are comparable to larger natural earthquakes (McLaskey et al., Pure and Applied Geophysics, 2014). This result indicates that stress drop is independent of seismic moment, a concept proposed by Keiiti Aki.
Greg is now building an experimental lab at Cornell, and his unique blend of seismology and rock friction studies has great potential to further our understanding of the physics of earthquake faulting.
—Karen M. Fischer, Brown University, Providence, R.I.
I am deeply honored to receive this year’s Aki award. I would like to thank my graduate adviser, Steve Glaser, for creating such a great experimental laboratory and for the freedom to “play” with seismology in that lab. It was by experimenting with different materials, sensors, and laboratory seismic sources such as ball impact and fracture that I was able to build my intuition about the way seismic waves are generated and propagated. I would also like to thank Roland Bürgmann for broadening my view of Earth science, for his encouragement, and for welcoming me in his lab meetings. Finally, I would not be where I am today without my fantastic colleagues and mentors at the earthquake science center at the USGS in Menlo Park. In particular, Nick Beeler was supportive of me from day one. Brian Kilgore: thanks for not letting anyone retire that 2-meter apparatus and for dedicating so much time to it. Dave Lockner: it has been so exciting to work with you and to write papers together. I look forward to continuing laboratory earthquake experiments that explore more closely their physics, mechanics, and scaling relationships.
—Gregory C. McLaskey, Cornell University, Ithaca, N.Y.
Citation: AGU (2015), McLaskey receives 2014 Keiiti Aki Young Scientist Award, Eos, 96, doi:10.1o29/2015EO028033. Published on 13 April 2015.