Dr. Andy Elwood Madden

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Frank and Henrietta Schultz Chair and Professor
School of Geosciences, University of Oklahoma

100 East Boyd St., Room SEC 956
amadden@ou.edu

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


Director, Samuel Roberts Noble Microscopy Laboratory

I work with the campus core microscopy team, manage the Geosciences powder X-ray diffraction lab, and am faculty supervisor for the Electron Microprobe Laboratory.


My students and I investigate the influence of nanoscale materials and processes on the chemistry of environmental systems.   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.
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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:

  • Wijdan Aljabri, UG, Clay chemical signatures of reductive fluid alteration
  • Cynthia Andrade, UG, powder X-ray diffraction laboratory and Raman laboratory researcher
  • Brock Dumont, UG, GeoKit mineral-based curriculum for 5-12 grade (OK Geological Foundation)
  • Logan Garrett, UG, Comparison of commercial nanodiamond and copper nanoparticles to sediment-extracted putative nanodiamonds
  • Zach Tomlinson, M.S., Impact of well pumping on trace metals in the Central Oklahoma Aquifer
  • Joshua Wester, UG, Size-dependent reactivity of hematite with sulfide; field versus lab comparison

Recent students with thesis/dissertation projects:

  • Brandon Maples, M.S., Evaluating cation exchange as a driver for manganese release during carbonate dissolution
  • Desiree Hullaster, M.S., “Redox interfaces in the proximal Permian Cutler Formation, Mesa County, western Colorado” (now with Hunt Oil)
  • 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 researcher at TAMU)
  • Andrew Swindle, Ph.D., “Size-dependent reactivity of magnetite nanoparticles: a bridge between laboratory and field investigations” (now Associate Prof. at Wichita State University)