Chad Wittkop

 Professor of Geology

Department of Biochemistry, Chemistry, and Geology

Minnesota State University

Mankato, MN 56001


Email: chad.wittkop@mnsu.edu

Phone: 507.389.6929

Office: Ford Hall 144


Interests: Sedimentary Geology, Biogeochemistry,

Geochemistry, Limnology, Glacial Geology


Research | Publications | Teaching






I use the geochemistry of sediments and water to broaden our understanding of the geologic record and the environment. Most of my projects explore problems in biogeochemistry, and involve lakes or glacial systems. To perform this work my students and I utilize MSU’s X-ray diffraction (XRD), X-ray fluorescence (XRF), and scanning electron microscopy (SEM) instrumentation in conjunction with work at various field sites, and specialized work in the labs of global network of collaborators.


I am perpetually interested in expanding the range of analytical techniques employed in these projects. In particular I encourage students with interests in analytical chemistry and microbiology to contact me to discuss research opportunities.


Current projects:


Biogeochemical cycling in ferruginous systems. Ferruginous (iron-enriched) environments are relatively rare today, but dominated the Archean and Proterozoic oceans which incubated life on Earth. I am working with a team of collaborators (see publications below) to improve our basic understanding of biogeochemical processes under ferruginous conditions. Project topics range from the role of bacteria in mineral genesis, to processes that govern Earth’s methane cycle, to mechanisms driving manganese enrichment in the geologic record. These projects utilize modern ferruginous lakes (see Lambrecht et al., 2018) as well as examples of ferruginous sediments ranging in age from Holocene (e.g. Wittkop et al., 2014) to the Proterozoic sediments of the Animikie Basin. Through much of this work I maintain a common interest in carbonate minerals, which may host multiple morphological and geochemical biosignatures, and be preserved across billions of years of geologic time.


Project funding: National Science Foundation (active through 2021), Huron Mountain Wildlife Foundation, MSU Faculty Research Grant.


Image above: Ferruginous carbonate varves and carbonate crystals from Otter Lake, Michigan (Wittkop et al., 2014).


Geochemistry of glacial tills. Glacial sediments record geochemical signatures of their source areas (provenance) as well as their transport processes. Exploring these signatures may lead to improved understanding of Pleistocene ice sheet dynamics, and inform resource management, including groundwater quality and soil health. In Minnesota, contrasting source regions created glacial sediments with highly variable geochemistry (figure below from Wittkop et al., 2020a). Collaborators (including Gustavus Adolphus and the Minnesota Geological Survey) and I are investigating application of a range of geochemical techniques to these materials including radiogenic isotope and detrital thermochronology, which promise to deepen our knowledge of Pleistocene sediment provenance and its environmental influence.



Maps above: Pleistocene sediment provenance and glacial ice lobes in Minnesota. Adapted from Wittkop et al., 2020a.


Other projects. Past projects have explored questions relating to Holocene landscape development and Earth surfaces processes (e.g. Gran et al. 2013), to how human impact is recorded in lake sediments (e.g. Ekdahl et al., 2004). I have contributed to geologic mapping efforts in New Hampshire and Montana, and collaborated informally with many others across a range of disciplines. See my publication list below for details, or feel free to contact me if you have questions.



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(*undergraduate student author)


Wittkop, C., and Perignon, M., 2021. Decadal-scale evolution of the 2006 Suncook River avulsion, New Hampshire, USA. Geomorphology, v. 376, 107572.


Swanner, E.D., Lambrecht, N., Wittkop, C., Harding, C., Katsev, S., *Torgeson, J., and Poulton, S.W., 2020. The biogeochemistry of ferruginous lakes and past ferruginous oceans. Earth-Science Reviews, v. 211, 103430.


Cole, D.B., Planavsky, N.J., Longley, M., Boning, P., Wilkes, D., Wang, X., Swanner, E.D., Wittkop, C, Loydell, D., Busigny, V., Knudsen, A., and Sperling, E.A., 2020. Uranium isotope fractionation in non-sulfidic anoxic settings and the global uranium isotope mass balance. Global Biogeochemical Cycles, doi: 10.1029/2020GB006649.


Wittkop, C., Swanner, E., Lambrecht, N., Fakrhaee, M., Myrbo, A., *Grengs, A., Bray, A., Poulton, S., and Katsev, S., 2020b. Evaluating a primary carbonate pathway for manganese enrichments in reducing environments. Earth and Planetary Science Letters, v. 538, 116201.


Wittkop C., Bartley, J., Krueger, R., Bouvier, A., Georg, R.B., *Piper, C., Knaeble, A., St. Clair, K., and Breckenridge, A., 2020a. Influence of provenance and transport process on the geochemistry and radiogenic (Hf, Nd, and Sr) isotopic composition of Pleistocene glacial sediments, Minnesota USA. Chemical Geology, v. 532, doi: 10.1016/j.chemgeo.2019.119390.


Lambrecht, N., Katsev, S., Wittkop, C., Hall, S.J., Sheik, C.S., Picard, A., Fakhraee, M., and Swanner, E.D., Biogeochemical and physical controls on methane fluxes from two meromictic ferruginous lakes. Geobiology, doi: 10.1111/gbi.12365


Van Dijk, J., Fernandez, A., Storck, J.C., White, T., Lever, M., Muller, I., Bishop, S., Seifert, R.F., Driese, S.G., Krylov, A., Ludvigson, G.A., Turchyn, A.V., Lin, C.Y., Wittkop, C., and Bernasconi, S.M., 2019. Experimental calibration of clumped isotopes in siderite between 8.5 and 800 °C and application as a paleo-thermometer in soils. Geochimica et Cosmochimica Acta, v. 254, p. 1-20.


Lambrecht, N., Wittkop, C., Katsev, S., Fakhraee, M., and Swanner, E.D., Geochemical characterization of two ferruginous meromictic lakes in the Upper Midwest, USA, 2018. Journal of Geophysical Research – Biogeosciences, v. 123, p. 3403-3422.


Mahoney, J.B., Pignotta, G.S., Ihinger, P.D., Wittkop, C., Balgord, E.A., Potter, J.J., and Leistikow, A., 2015. Geologic relationships in the northern Helena Salient, Montana: Geology of the Elliston Region. Northwest Geology, v. 44, p. 109-136.


Wittkop, C., Teranes, J., Lubenow, B., and Dean, W.E., 2014. C- and O-stable isotopic signatures of methanogenesis, temperature, and water column stratification in Holocene siderite varves. Chemical Geology, v. 389, p. 153-166.


Gran, K.B., Finnegan, N., Johnson, A.L., Belmont, P., Wittkop, C., and Rittenour, T., 2013. Landscape evolution, valley excavation, and terrace development following abrupt postglacial base-level fall. Geological Society of America Bulletin, v. 125, p. 1851-1864. 2018 Recipient of GSA Kirk Bryan Award for Excellence.


Miller, J.D., Hudak, G.J., Wittkop, C., and McLaughlin, P.I., (Eds.), 2011. Archean to Anthropocene: Field Guides to the Geology of the Mid-Continent of North America. Geological Society of America Field Guide 24, 544 p.


Belmont, P., Gran, K., Jennings, C.E., Wittkop, C., and Day, S.S., 2011. Holocene landscape evolution and erosional processes in the Le Sueur River, central Minnesota. In: Miller, J.D., Hudak, G.J., Wittkop, C., and McLaughlin, P.I., (Eds.), Archean to Anthropocene: Field Guides to the Geology of the Mid-Continent of North America. Geological Society of America Field Guide 24, p. 439-455.


Schirmer, R.C., and Wittkop, C., 2011. Application of LiDAR and geophysics to archaeological investigations in the upper Mississippi River valley. In: Miller, J.D., Hudak, G.J., Wittkop, C., and McLaughlin, P.I., (Eds.), Archean to Anthropocene: Field Guides to the Geology of the Mid-Continent of North America. Geological Society of America Field Guide 24, p. 401-410.


Balgord, E.A., Mahoney, J.B., Pignotta, G.S., Wittkop, C., King, N.E., Ihinger, P.D., Hardel, B.G., and Kadulski, B., 2010. Geologic Map of the Esmeralda Hill 7.5’ quadrangle, Lewis and Clark County and Powell County, Montana. Montana Bureau of Mines and Geology EDMAP 8, one sheet. Map scale 1:24,000.


MacLaurin, C., Mahoney, J.B., Guy, A., Forgette, M., Kjos, A., Wittkop, C., Kohel, C., Balgord, E., Barber, B., and Ihinger, P.D., 2010. Geologic Map of the Dunn Creek 7.5’ quadrangle west-central Montana. Montana Bureau of Mines and Geology EDMAP 9, one sheet. Map scale 1:24,000.


Wittkop, C., Teranes, J., Dean, W.E., and Guilderson, T., 2009. A lacustrine carbonate record of Holocene seasonality and climate. Geology v. 37, p. 695-698.


Wittkop, C., 2008.  Surficial Geologic Map of the Gilmanton Ironworks Quadrangle, Belknap County, New Hampshire.  New Hampshire Department of Environmental Services Open-File Map, one sheet.  Map scale 1:24,000.


Franzi, D., Koteff, C., and Wittkop, C., 2008.  Surficial Geologic Map of the Concord Quadrangle Merrimack County, New Hampshire.  New Hampshire Department of Environmental Services Open-File Report (GIS Coverage and Color Map), one sheet.  Map scale 1:24,000.


Wittkop, C., Bennett, D., Chormann, R., and Wunsch, D., 2007.  Geology of the May 2006 Suncook River avulsion.  Guidebook to Field Trips in New Hampshire, Adjacent Maine, and Massachusetts.  42nd Annual Meeting, Northeastern Section Geological Society of America, p. 45-55. 


Ekdahl, E.J., Teranes, J.L., Wittkop, C.A., Stoermer, E.F., Reavie, E.D., and Smol, J.P., 2007. Diatom assemblage response following Iroquoian and Euro-Canadian eutrophication of Crawford Lake, Ontario, Canada. Journal of Paleolimnology, v. 37, p. 233-246


Bennett, D., Wittkop, C., and Dicken, C., 2006. Bedrock Geologic Map of New Hampshire—A Digital Representation of the Lyons and others 1997 map and ancillary files.  U.S. Geological Survey Data Series 215 (CD ROM).


Ekdahl, E.J., Teranes, J.L., Guilderson, T.P., Turton, C.F., McAndrews, J.H., Wittkop, C.A., and Stoermer, E.F., 2004. A prehistorical record of cultural eutrophication from Crawford Lake, Ontario. Geology, v.  32, p. 745-748.



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All of the research projects above have employed MSU Geology students, and provide them with opportunities for travel, resume building, and discovery (aka, fun). Many projects are supported by MSU’s Undergraduate Research Center. Below is a list of current and former research students. The majority of these projects were presented at regional or national meetings (student name, funding source, project):


Emily Faust, URC, Geochemistry and mineralogy of the Proterozoic Freedom Formation

Brian Niedzielski, MSU, Manganese enrichment in the Biwabik Iron Formation

Ashley Grengs, NSF, Ferruginous lake mineral solubility

Duncan Widman, NSF, Ferruginous lake particulates and pottery characterization by SEM, XRD, and XRF

Christian Piper (Chemistry), URC, Pleistocene till provenance by XRD and XRF

Josh Torgeson, URC, Iron carbonates in lacustrine systems

Dan Scheeler, URC, Sediment Fingerprinting and Till Stratigraphy in Southern Minnesota

Samantha Richard, Bedrock control on pothole development, Interstate Park Minnesota

Ryan Bonney, URC, Sediment Fingerprinting in Southern Minnesota

Brady Lubenow (M.S. Candidate, University of Idaho), 2 URC Foundation Awards, Iron Carbonates in Minnesota and Michigan

Tyler Boley, URC, Geologic Mapping in Montana

Ryan Bleess, Geological Society of America (GSA), Geologic Mapping in Montana

Questor German, URC, Geologic Mapping in Montana

Kyle Makovsky (M.S., Boise State), GSA, Bedrock Geology of the Le Sueur River Paleochannel.

Kate Meixell, URC Foundation Award, OSL Chronology of the Le Sueur River Capture




Minnesota State – Mankato (2007-present):


GEOL 100 – Our Geologic Environment (with lab)

GEOL 108 – Oceans of the World (online)

GEOL 121 – Physical Geology (with lab)

GEOL 122 – Earth History (with lab)

GEOL 310 – Earth and Space Systems

GEOL 320 – Sedimentology and Stratigraphy (with lab and field trip)

GEOL 410 – Glacial Geology (with field and lab exercises)


GEOL 320 students on location in Wyoming being good sports about the snow, (early) October 2012.


University of Wisconsin – Eau Claire (2006-2007):


Physical Geology (with lab)

Earth Resources

Field Excursion (field trip to Death Valley, California and vicinity)




I frequently provide customized presentations to local organizations and schools of all interest levels. In the past I’ve worked with Le Sueur Middle School, Friends of Minneopa State Park, the Department of Natural Resources, Interstate State Park, and Mankato Cub Scouts. My colleagues and I in Geology also meet and consult with interested community members regarding water quality, rock identification, and the geologic history of the region. Feel free to contact me if you think I can be of assistance to you or your organization.


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