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I collect and study xenoliths, rocks that come up from lower crust and upper mantle depths through volcanic eruptions.

My research aims to understand the rheological properties of the lower crust and upper mantle, primarily in the Mojave region of Southeastern California. I'm also actively working on understanding the factors that influence the development of olivine lattice preferred orientation (LPO) more generally. Recently, I've been working towards investigating the effects water and stress have on olivine LPO "types", to see how well naturally deformed samples agree with the relationships predicted by experiments (e.g., Jung et al. 2006). I'm also really excited about the preservation of LPO in annealed peridotites, and what that can tell us about interpretation of seismic anisotropy. All of these projects are still works in progress, so stay tuned!

Bernard, R. and W. Behr (2017) Fabric heterogeneity in the Mojave lower crust and lithospheric mantle in Southern California. JGR Solid Earth. DOI: 10.1002/2017JB014280


One tool I use to investigate the rheological properties of these rocks is Electron Backscattered Diffraction (EBSD). This tool allows for the identification of mineral phases based on crystallographic properties, and also determines the orientations of those minerals. Below: (top) phase map of an awesome, highly deformed peridotite xenolith from Lunar Craters Volcanic Field in central Nevada; (bottom) the same mapped area, but with olivine colored based on orientation. This map clearly shows all the subgrain development, dynamic recrystallization, and spectacularly elongated grains preserved in this rock.