- Ph.D. (1997) Geophysics, University of Minnesota
- M.S. (1990) Geophysics, Indiana University
- B.S. (1987) Geology, Eastern Illinois University
My overall research interest is in mineral and rock physics, with an emphasis on the rheological behavior of Earth and planetary materials. I am an experimental geophysicist, that is, I apply modern theories and methods of materials science to understand geophysical processes at large scales. In the next five years, my goal is to focus on experiments designed to further our understanding of deformation mechanisms in the Earth and other planets. Experiments are conducted at high confining pressure and at ambient pressure, at high temperatures in the case of materials like olivine and at cryogenic emperatures in the case of ice and other cryomaterials. Experiments employ methods developed in materials science for fabricating and testing of materials, such as hot isostatic pressing of fine-grained samples to explore grain size-sensitive creep, and nanoindentation testing to explore deformation processes at small scales. One particular focus of my research has been grain size-sensitive flow of materials, a creep behavior which involves grain boundary sliding. This flow behavior dominates at lower stresses than for dislocation creep, and therefore can control the rheological behavior of materials in low-deviatoric-stress natural environments, such as in glaciers and icy satellites, as well as in the interiors of the Earth and other planets.
Within the broader scope of mineral and rock physics, there are several specific research topics I am currently studying:
1) the rheological behavior of pure and impure ices relevant to flow of glaciers, ice sheets, and icy satellites of the outer solar system,
2) the tribological behavior of rocks relevant to earthquake mechanics, and
3) low-temperature creep of geologic materials relevant to the frictional properties of rocks and the strength of the lithosphere