Associate Professor
School of Geology and Geophysics, University of Oklahoma

100 East Boyd St., Room SEC 924


Postdoctoral Research Associate, 2005-2007, Oak Ridge National Laboratory
Ph.D. (geochemistry), 2005, Virginia Tech
B.S. (geology), 2000, Michigan State University

My students and I investigate the influence of nanoscale materials and processes on the chemistry of environmental systems.   I manage the powder X-ray diffraction lab. We undertake studies to:

  • understand how size-dependent properties of nanoscale minerals influence natural and human-impacted environmental biogeochemical processes,
  • understanding the roles of nanoscale biogeochemical processes in mediating toxic element/compound release or sequestration, in order to
    • support sustainable water resources and practices and
    • create knowledge that aids in the interpretation of Earth’s geologic record, and
  • create new nanoscale solutions to emerging challenges at the intersection of Earth’s dynamic processes, natural resources, and human society.
See the research page for more details about recent research projects, or the publications page to see what we’ve been up to in our group and with collaborations.

Current students with projects:

  • Desiree Hullaster, M.S., Relationships between methane oxidation, groundwater geochemistry, and microbial communities in extreme environments
  • Brandon Maples, M.S., Mechanisms of Cr(III) release and oxidation in the Central Oklahoma Aquifer
  • Kourtney Lewis, B.S., Size-dependent reactivity of minerals: comparison of laboratory and field experiments
  • Emma Bachman, B.S., Characterization of biofilm-associated minerals from methane-bearing extreme environments

Recent students with thesis/dissertation projects:

  • Molly Sexton, M.S., “Stratigraphic and textural analysis of nanodiamonds across the Younger Dryas boundary sediments of western Oklahoma” (now with EPA)
  • Jeff Westrop, M.S., “The geochemistry of chromium in the Central Oklahoma Aquifer, Norman, OK” (now in Ph.D. program at Nebraska)
  • Brett Weeks, B.S., “Correlation between dolomite saturation and chromium concentrations within the Central Oklahoma Aquifer”
  • Xiaofeng Chen, Ph.D. (with Reches), “Rock friction and dynamic faulting at the micro- to nano-scales” (now postdoctoral researcher at UT-Austin)
  • Andrew Swindle, Ph.D., “Size-dependent reactivity of magnetite nanoparticles: a bridge between laboratory and field investigations” (now Assistant Prof. at Wichita State University)

Students I advise share a research group with Dr. Megan Elwood Madden and her advisees.