Ph.D. University of Rochester
Montague – Center for Teaching Excellence Scholar, Texas A&M University, (2010)
Structural geology and tectonics
My research is in the fields of structural geology and tectonics. My students and I carry out field, microstructural and experimental studies of crustal and upper mantle rocks to investigate the rheology, or strength and behavior, of the earth’s lithospheric layers. Currently, we are working on ultramafic rocks from mantle massifs in western Washington, New Zealand, and California, as well as low-temperature thrust faults from the foreland of the southern Appalachians. When studying rocks from different crustal and upper mantle environments, we investigate deformation processes, such as mechanisms of strain localization, the influence of fluid-rock interactions on deformation, and interactions between deformation and metamorphism. By combining field data and deformation microstructures with the geochemistry of deformed rocks, we can determine the conditions of deformation, including pressures, temperatures, stresses and strain-rates.
Some of the tools we use to carry out this work include fieldwork, optical microscopy and electron microscopy, including the electron microprobe and the scanning electron microscope with electron backscattered diffraction (EBSD).
Holyoke, C.W., III, Kronenberg, A.K., Newman, J. (2014) Microstructural evolution during strain localization in dolomite aggregates. Journal of Structural Geology, doi: 10.1016/j.jsg.2014.04.008
Wells, R.K., Newman, J., Wojtal, S.F. (2014) Microstructures and rheology of a calcite-shale thrust fault, Journal of Structural Geology (65), pp. 69-81, doi: 10.1016/j.jsg.2014.04.002
Tikoff, B, Blenkinsop, T., Kruckenberg, S.C., Morgan, S., Newman, J., Wojtal, S. (2013) A perspective on the emergence of modern structural geology: Celebrating the feedbacks between historical-based and process-based approaches, in: (ed., M.E. Bickford) Geological Society of America 125th Anniversary Special Publication.
Holyoke III, C.W., Kronenberg, A.K., Newman, J. (2013) Dislocation creep of polycrystalline dolomite, Tectonophysics, doi: 10.1016/j.tecto.2013.01.011
Kruckenberg, S.C., Tikoff, B., Toy, V.G., Newman, J., Young, L. (2013) Strain localization associated with channelized melt flow in upper mantle lithosphere: insights from the Twin Sisters ultramafic complex, Washington, USA. Journal of Structural Geology Special Issue: Deformation Localization in Rocks, v. 50, pp. 133-147. doi.org/10.1016/j.jsg.2012.10.009
*Davis, N.E., Newman, J., Wheelock, P. and Kronenberg, A.K. (2011) Grain growth kinetics of dolomite and magnesite. Physics and Chemistry of Minerals (38), pp. 123-138, doi: 10.1007/s00269-010-0389-9.
Tikoff, B., *Larson, C.E., Newman, J., Little, T. (2010) Field-based constraints on rheology of the lithospheric mantle, Twin Sisters, Washington. Lithosphere (2), pp. 418-422, doi: 10.1130/L97.1.
Newman, J. and Drury, M.R. (2010) Control of shear zone location and thickness by initial grain size variations in upper mantle peridotites. Journal of Structural Geology (32) pp. 832-842, doi:10.1016/j.jsg.2010.06.001.
*Webber, C., Newman, J., Holyoke, C., Little, T., Tikoff, B., (2010) Fabric development in cm-scale shear zones in ultramafic rocks, Red Hills, New Zealand. Tectonophysics (489) pp. 55-75, doi: 10.1016/j.tecto.2010.04.001
**Toy, V., Newman, J., Lamb, W.M., Tikoff, B. (2010) The role of pyroxenites in formation of shear instabilities in the mantle: Evidence from an ultramafic ultramylonite, Twin Sisters Massif, Washington. Journal of Petrology (51), pp. 55-80, doi:10.93/petrology/egp059