Title: Assistant Professor
Room: GE 007A
Ph.D., 2013, University of Oklahoma
M.S., 2003, Oklahoma State University
B.S., 1999, Oklahoma State University
Wichita State University – Assistant Professor (2014-present)
University of Oklahoma – Postdoctoral Research Associate (2013-2014)
University of Oklahoma – Teaching and Research Assistant (2009-2013)
URS – Staff Hydrogeologist (2008-2009)
Weaver Boos Consultants – Staff Geologist (2005-2008)
SCS Engineers – Staff Geologist (2004-2005)
Secor International – Staff Technician (2004)
My main research area focuses on the reactivity of nanoscale materials in the subsurface. Nanoscale minerals are ubiquitous in the environment and play major roles in the chemistry that happens in the soils, sediments, and rocks near the Earth’s surface. Broadly speaking, I am interested in how the combination of nanoparticles and geochemistry can contribute to the transport of a contaminant in the environment. I also approach the issue from the other side and investigate the fate of anthropogenic nanomaterials in the environment. Some of my other research interests include: the hydrogeology of karst systems, materials analysis, and planetary geology.
Some representative projects:
Impact of natural organics on the surface reactivity of goethite nanoparticles
Naturally occurring nanoparticles have the ability to sorb contaminants such as heavy metals; thereby sequestering them and prevent migration in the subsurface. Researchers are exploring the use of anthropogenic nanoparticles injected into the subsurface to do the same thing. Unfortunately, naturally occurring organic materials also readily adsorb onto the surface of these particles. The more organics adsorbed, the lower the ability of the nanoparticle to sorb contaminants. This research investigates how variables such as type of organic, mineral-organic contact time, and water chemistry impact the sorption of heavy metals onto goethite nanoparticles in the presence of natural organics.
Student researcher: Stacey Hales
Mineralogy of colloidal materials in soil at the Ninnescah Biological Field Station
Colloids are materials that range in size from 1 – 1000 nanometers (the smallest colloids are nanoparticles). Naturally occurring colloids are responsible for a great deal of the chemistry that happens in soils. So if we want to predict what will happen in a soil when say, it is exposed to a contaminant, we need to know something about the colloids that are in the soil. This work seeks to identify and quantify the colloidal fraction of soils from the WSU Ninnescah Biological Field Station using a combination of sieving, wet chemistry, UV-VIS photospectrometry, and XRD.
Researcher: Will Swanson
GEOL 690AK/724: Soils
GEOL 650: Hydrogeology
GEOL 560/810AG: Geomorphology and Land Use
GEOL 102: Earth Science and the Environment
EEPS 702: Research Methods
Swindle AL, Madden AS, Cozzarelli IM (2015). Using chromate to investigate the impact of natural organics on the surface reactivity of nanoparticulate magnetite. Environmental Science and Technology, 49 (4), pp 2156 – 2162
Swindle AL, Madden AS, Cozzarelli IM, Benamara M (2014). Size-dependent reactivity of magnetite nanoparticles: A field-laboratory comparison. Environmental Science and Technology, 48 (19), pp 11413 – 11420
Bement, LC, Madden AS, Carter BJ, Sims AR, Swindle AL, Alexander HM, Fine S, Benemara M (2013). Prospecting for nanodiamonds in equivalent deposits of different age for Younger Dryas Verification, Proceedings of the National Academy of Sciences, 111, 1726-1731.
Madden AS, Swindle AL, Beazley MJ, Moon J-W, Ravel B, Phelps TJ (2012). Long-term solid-phase fate of coprecipitated U(VI)-Fe(III) following biological iron reduction by Thermoanaerobacter, American Mineralogist, 97, 1641-1652.