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Congratulations to David Goldsby and Christopher Thom on their Science Advances paper

EES PhD Candidate Chris Thom and Associate Professor David Goldsby coauthored a Science Advances paper demonstrating via nanoindentation testing that the strength of olivine, the primary mineral in the Earth’s upper mantle, depends on the length scale of deformation, with experiments on smaller volumes of material exhibiting larger yield stresses. This “size effect” resolves the discrepancies among previous measurements of olivine strength using other testing methods, and brings experimental measurements of the yield stress of olivine into close alignment with geophysically-constrained values.  

Citation: “Size effects resolve discrepancies in 40 years of work on low-temperature plasticity in olivine, Kathryn M. Kumamoto, Christopher A. Thom, David Wallis, Lars N. Hansen, David E. J. Armstrong, Jessica M. Warren, David L. Goldsby, Angus J. Wilkinson,


Department of Earth and Environmental Science / University of Pennsylvania, 251 Hayden Hall, 240 South 33rd Street, Philadelphia, PA 19104-6316