Carleton Bern, PhD
I am a research soil scientist with the U.S. Geological Survey in the Colorado Water Science Center. My research examines the geochemical interactions between water, rock, and soil. Water quality in relation to agriculture, mining, and hydrocarbon extraction is the focus of my current projects. I am also developing novel modeling approaches to trace the influence of colloids on soil development.
Biography
Education
Ph.D. Ecology and Evolutionary Biology University of Colorado, Boulder, CO 2006
B.S. Biology, Virginia Tech, Blacksburg, VA 1996
Professional Experience
Research Soil Scientist, U.S. Geological Survey 2010-present
Mendenhall Postdoctoral Fellow, U.S. Geological Survey 2008-2010
Post-doctoral Researcher, University of California, Santa Barbara 2006-2008
Biologist, Stable Isotope Laboratory, U.S. Geological Survey 2004-2006
Selected Publications:
Bern, C.R., Yesavage, T. 2018. Dual-phase mass balance modeling of small mineral particle losses from sedimentary rock-derived soils. Chemical Geology. https://doi.org/10.1016/j.chemgeo.2017.11.040
Bern, C.R. and Stogner, R.W. Sr. 2017. The Niobrara Formation as a challenge to water quality in the Arkansas River, Colorado, USA. Journal of Hydrology: Regional Studies. https://doi.org/10.1016/j.ejrh.2017.05.001 (Open access)
Bern, C.R., T. Yesavage, and N.K. Foley. 2017. Ion-adsorption REEs in regolith of the Liberty Hill pluton, South Carolina, USA: An effect of hydrothermal alteration. Journal of Geochemical Exploration 172:29-40, https://doi.org/10.1016/j.gexplo.2016.09.009
Bern,C.R., Shah, A.K., Benzel, W.M., Lowers, H.A. 2016. The distribution and composition of REE-bearing minerals in placers of the Atlantic and Gulf coastal plains, USA. Journal of Geochemical Exploration. https://doi.org/10.1016/j.gexplo.2015.12.011
Bern, C.R., Thompson, A., Chadwick, O.A. 2015. Quantification of colloidal and aqueous element transfer in soils: The dual-phase mass balance model. Geochimica et Cosmochimica Acta. https://doi.org/10.1016/j.gca.2014.12.008
Bern, C.R., Clark, M.L., Schmidt, T.S., Holloway, J.M., McDougal, R.R., 2015. Soil disturbance as a driver of increased stream salinity in a semiarid watershed undergoing energy development.Journal of Hydrology, 524: 123-136, https://doi.org/10.1016/j.jhydrol.2015.02.020.
Bern C.R., Breit, G.N., Healy, R.W., Zupancic, J., Hammack. R. 2013 Deep subsurface drip irrigation using coal-bed sodic water: Part I. Water and solute movement. Agricultural Water Management. https://doi.org/10.1016/j.agwat.2012.11.014
Bern C.R., Breit, G.N., Healy, R.W., Zupancic, J. 2013. Deep subsurface drip irrigation using coal-bed sodic water: Part II. Geochemistry. Agricultural Water Management. https://doi.org/10.1016/j.agwat.2012.11.013
Bern, C.R., Chadwick, O.A., Hartshorn, A.S., Khomo, L.M., Chorover, J. 2011. A mass-balance model to separate and quantify colloidal and solute redistributions in soil. Chemical Geology. https://doi.org/10.1016/j.chemgeo.2011.01.014
Bern, C.R., Brzezinski, M.A. Beucher, C., Ziegler, K., and Chadwick, O.A. 2010. Weathering, dust and biocycling effects on soil silicon isotope ratios. Geochimica et Cosmochimica Acta. https://doi.org/10.1016/j.gca.2009.10.046
Bern, C. R. 2009. Soil chemistry in lithologically diverse datasets: The quartz dilution effect. Applied Geochemistry, 24: 1429-1437, https://doi.org/10.1016/j.apgeochem.2009.04.013
Bern, C. R., A. R. Townsend, and G. L. Farmer. 2005. Dominance of parent-material strontium in a tropical forest on highly weathered soils. Ecology 86(3): 626-632. https://doi.org/10.1890/03-0766
Science and Products
Improved enrichment factor calculations through principal component analysis: Examples from soils near breccia pipe uranium mines, Arizona, USA
The enrichment factor (EF) is a widely used metric for determining how much the presence of an element in a sampling media has increased relative to average natural abundance because of human activity. Calculation of an EF requires the selection of both a background composition and a reference element, choices that can strongly influence the...
Bern, Carleton R.; Walton-Day, Katie; Naftz, David L. Colloid mobilization and seasonal variability in a semiarid headwater stream
Colloids can be important vectors for the transport of contaminants in the environment, but little is known about colloid mobilization at the watershed scale. We present colloid concentration, composition, and flux data over a large range of hydrologic conditions from a small watershed (Gordon Gulch) in the foothills of the Colorado Front Range....
Mills, Taylor J.; Suzanne P. Ancerson; Bern, Carleton R.; Aguirre, Arnulfo; Derry, Louis A. Iron isotope systematics of shale-derived soils as potentially influenced by small mineral particle loss
Loss of small mineral particles from soil has been suggested as a process that can produce net isotopic fractionation in the remaining soil. We extracted water dispersible colloids (WDCs) from bulk soil collected at the Susquehanna/Shale Hills Critical Zone Observatory (SSHO) and measured their Fe isotopic composition for comparison to published...
Bern, Carleton R.; Yesavage, Tiffany; Pribil, Michael Modifications to EPA Method 3060A to Improve Extraction of Cr(VI) from Chromium Ore Processing Residue-Contaminated Soils
It has been shown that EPA Method 3060A does not adequately extract Cr(VI) from chromium ore processing residue (COPR). We modified various parameters of EPA 3060A toward understanding the transformation of COPR minerals in the alkaline extraction and improving extraction of Cr(VI) from NIST SRM 2701, a standard COPR-contaminated soil. Aluminum...
Mills, Christopher T.; Bern, Carleton R.; Wolf, Ruth E.; Foster, Andrea L.; Morrison, Jean M.; Benzel, William M. Rare earth mineral potential in the southeastern U.S. Coastal Plain from integrated geophysical, geochemical, and geological approaches
We combined geophysical, geochemical, mineralogical, and geological data to evaluate the regional presence of rare earth element (REE)−bearing minerals in heavy mineral sand deposits of the southeastern U.S. Coastal Plain. We also analyzed regional differences in these data to determine probable sedimentary provenance. Analyses of heavy mineral...
Shah, Anjana K.; Bern, Carleton R.; Van Gosen, Bradley S.; Daniels, David L.; Benzel, William M.; Budahn, James R.; Ellefsen, Karl J.; Karst, Adam; Davis, Richard The Niobrara Formation as a challenge to water quality in the Arkansas River, Colorado, USA
Study regionArkansas River, east of the Rocky Mountains.Study focusCretaceous sedimentary rocks in the western United States generally pose challenges to water quality, often through mobilization of salts and trace metals by irrigation. However, in the Arkansas River Basin of Colorado, patchy exposure of multiple Cretaceous formations has made it...
Bern, Carleton R.; Stogner, Sr., Robert W. The distribution and composition of REE-bearing minerals in placers of the Atlantic and Gulf coastal plains, USA
Rare earth element (REE) resources are currently of great interest because of their importance as raw materials for high-technology manufacturing. The REE-phosphates monazite (light REE enriched) and xenotime (heavy REE enriched) resist weathering and can accumulate in placer deposits as part of the heavy mineral assemblage. The Atlantic and Gulf...
Bern, Carleton R.; Shah, Anjana K.; Benzel, William M.; Lowers, Heather A.