Stephen Grand Receives the Inge Lehmann Medal

February 19, 2023

Professor Steven Grand was awarded the 2022 Inge Lehmann Medal by the American Geophysical Union. The prestigious medal recognizes outstanding contributions to the understanding of the structure, composition, and dynamics of Earth’s mantle and core. Grand joined The University of Texas at Austin in 1986. His research has focused on seismically imaging Earth’s mantle. This has included an effort to develop a 3-D image of shear velocity throughout the mantle with the ultimate goal to determine the dynamics of flow in the mantle.

The citation by Dr. David Rowley of University of Chicago illustrates the importance of this award:

Few scientists’ work can honestly be claimed to have transformed the perception of how Earth works. If a picture is worth a thousand words, then it is true that Steve Grand’s tomographic images clearly resolving the subducted Farallon slab penetrating through the mid-mantle have transformed our understanding by demonstrating that Earth’s convective system necessarily involves the whole mantle. Steve, given his abundant modesty, would never ascribe to himself such an impact, but the vigorous debates that raged from the 1970s to the 1990s over layered versus whole-mantle convection were immediately put to rest with the 1994 publication, in the Journal of Geophysical Research, of his Atlantic-centered tomography that clearly revealed the Farallon slab at mid-mantle depths in both map and cross-sectional views. Of course, the iconic image that sealed the deal was the 1997 cover of GSA Today, “Global Seismic Tomography: A Snapshot of Convection in the Earth,” with Rob Van Der Hilst and S. Widiyantoro. To quote Dan McKenzie, “In my view he is the most wide ranging and careful observational seismologist now active.” In a fundamental sense, what characterizes Steve’s work throughout his career are two central components. First is the development and application of state-of-the-art tools to address first-order questions. Second is a remarkable ability to identify where to apply those tools to go after important problems that seismology can address using well-conceived and carefully executed analyses. Whether it is the clear imaging of the Farallon slab in the deep mantle, resolving the global distribution of density anomalies driving mantle dynamics, revealing the deep root of the Yellowstone plume, or remarkably detailed images of the mantle beneath eastern Asia, Steve has been a central driving force in bringing each of these endeavors to fruition. Together these advances have demonstrated Steve’s profound (literally and figurately) impact on seismology, both in global and regional tomography, and the Earth sciences writ large. Steve Grand has made critically important contributions to the understanding of the structure, composition and dynamics of Earth’s mantle. It is therefore entirely fitting and appropriate that Steve receive the 2022 Inge Lehmann Medal from AGU.

To see Dr. Grand’s response, check out the posting here for 2022