Clay Mineralogy
Professor & Department Head
Registered P.G.
Research Correspondence:

Contact Info

Geography-Geology Building, Room 301A

Current Research Interests

Clays and clay minerals are the most abundant reactive solids on the Earth's surface. Understanding clays minerals involves the detailed crystal-chemical characterization of their structure, particularly as they are found associated in the critical zone, which includes near surface weathering, diagenetic, and hydrothermal geologic environments. Clay minerals often interact with biological systems, which then allow them to proxy the record of environmental change throughout Earth history and perhaps in extraterrestrial environments. The research carried out in my group involves the study of these fine grain particles using NMR spectroscopy, Fourier transform IR and Raman spectroscopy, radiogenic, cosmogenic, and stable isotopes, chemical and thermal analyses, and X-ray and electron diffraction.

Research Interests:

Clays and clay minerals are nature's most common nano-material. The study of both natural and synthetic nano-composites made up of clays and organics offers great promise for the discovery of new materials for use in medical, pharmaceutical, and material industries. Knowledge of clays is essential for the exploration and exploitation of hydrocarbon energy, particularly in terms of benefiting the environment.

Selected Publications:

Complete publications are listed here.  Peer review journal articles are only listed below.

  • Lars Riber, Henning Dypvik, Ronald Sørlie , Syed Asmar Aal-E-Muhammad Naqvi, Kristian Stangvik, Nikolas Oberhardt, Paul A. Schroeder. 2017. Comparison of deeply buried paleoregolith profiles, Norwegian North Sea, with outcrops from southern Sweden and Georgia, USA - Implications for petroleum exploration. Palaeogeography, Palaeoclimatology, Palaeoecology 471: 82–95.
  • Schroeder, P.A. 2016 Clays in the Critical Zone: An Introduction.  Clays and Clay Minerals, v. 64(5) 486- 486. DOI: 10.1346/CCMN.2016.064045
  • Bozkaya, Ö., A. Günal-Türkmenoğlu, M. C. Göncüoğlu, Ö. Ünlüce, İ. Ö. Yilmaz and P. A. Schroeder 2016. "Illitization of Late Devonian-Early Carboniferous K-bentonites from Western Pontides, NW Turkey: Implications for their origin and age." Applied Clay Science 134: 257-274.
  • Cyle, K., N. Hill, K. Young, T. Jenkins, D. Hancock, P.A. Schroeder and A. Thompson 2016.  Substrate quality influences organic matter accumulation in the soil silt and clay fraction. Soil Biology and Biochemistry 103: 138-148.
  • Hatice Ünal Ercan, Ö. Işık Ece, Paul A. Schroeder, and Zekiye Karacık. 2016 Differentiating styles of alteration within kaolin-alunite hydrothermal deposits of Çanakkale, NW Turkey. Clays and Clay Minerals. Vol. 64, No. 3, 189–218.
  • E. Orucoglu, P. A. Schroeder 2016 Investigating the expanding behavior and thermal stability of HDPy modified organo-bentonite by X-ray diffraction technique.
  • Austin, Jason C. and Paul A. Schroeder. 2014 Assessment of pedogenic gibbsite as a paleo-PCO2 proxy using a modern Ultisol. Clays and Clay Minerals,Vol. 62, No 5, 235-266.
  • Paul A. Schroeder 2014  Kaolin: From ancient porcelains to nanocomposites.  Elements 10: 177-182.
  • Ömer I. Ece, Bala Ekinci, Paul A. Schroeder, Douglas Crowe and Fahri Esenli. 2013 Origin of the Düvertepe kaolin-alunite deposits in Simav Graben, Turkey: timing and styles of hydrothermal mineralization. Journal of Volcanology and Geothermal Research, Vol. 255, 57-78.
  • Yahya Ozpinar,  Baris Semiz , and Paul A. Schroeder. 2013 Zeolites In Mafic Pyroclastic Rocks From The Sandikli-Afyonkarahisar Region, Turkey. Clays and Clay Minerals, Vol. 61, No. 3, 177–192.
  • Mark A. Engle, Lawrence F. Radke, Edward L. Heffern, Jennifer M.K. O'Keefe, James C. Hower, Charles D. Smeltzer, Judith M. Hower, Ricardo A. Olea, Robert J. Eatwell, Donald R. Blake, Stephen D. Emsbo-Mattingly, Scott A. Stout, Gerald Queen, Kerry L. Aggen l, Allan Kolker, Anupma Prakash, Kevin R. Henke, Glenn B. Stracher, Paul A. Schroeder, Yomayra Román-Colón, Arnout ter Schure  2012 Gas emissions, minerals, and tars associated with three coal fires, Powder River Basin, USA Science of The Total Environment, Volume 420, 15 March 2012, Pages 146-159.
  • Diaz, M., Robert, J-L. Schroeder, P. A. and Prost, R. 2010 Far infrared study of the influence of the octahedral sheet composition on the K+-layer interactions in synthetic phlogopites. Clays and Clay Minerals, v. 58(2) 263-271.
  • Schroeder, P.A., 2010 Natural occurrence of elevated arsenic and selenium in Georgia regolith: Implications for their relative mobility in Piedmont soils. Southeastern Geology, v. 47, No. 1, p. 15-26.
  • Ece, Ö.I., Schroeder, P.A., Smilley, M. and Wampler, M. 2008 Acid-sulfate alteration of volcanic rocks and genesis of halloysite and alunite deposits in the Biga Peninsula, NW Turkey. Clay Minerals v.43, 281-315.
  • Kyle, Jennifer, Schroeder, P.A., and Wiegel, J. 2007 Microbial silicification in sinters from two terrestrial hot springs in the Uzon Caldera, Kamchatka, Russia. Geomicrobiology Journal. v. 24, 627-641.
  • Pone, J. Denis N., Kim A.A. Hein, Glenn B. Stracher, Harold J. Annegarn, Robert B. Finkleman, Donald R. Blake, John K. McCormack, Paul Schroeder. 2007 The spontaneous combustion of coal and its by-products in the Witbank and Sasolburg coalfields of South Africa, International Journal of Coal Geology, v. 72, 124-140.
  • Ö. Isik Ece and Schroeder, Paul A. 2007 Hydrothermal Alteration of Oligocene volcanic rocks and genesis of hallyosite-alunite-kaolinite deposits in the Turplu area, Balikesir, Turkey. Clays and Clay Minerals, 55(1), 18-36.
  • Kyle, Jennifer and Schroeder, Paul A. 2007 Role of smectite in siliceous sinter formation and microbial texture preservation: Octopus Spring, Yellowstone National Park, Wyoming, USA. Clays and Clay Minerals, v. 55(2): 189-199.
  • Schroeder, Paul A., Jason C. Austin, John F. Dowd 2006 Estimating long-term soil respiration rates from carbon isotopes occluded in gibbsite, Geochimica et Cosmochimica Acta. v. 70/23, 5692-5697
  • Glenn B. Stracher, Anupma Prakash, Paul A. Schroeder, John McCormack, Xiangmin Zhang, Paul van Dijk, and Donald Blake 2005 New mineral occurrences and mineralization processes: Wuda coal-fire gas vents of Inner Mongolia. American Mineralogists. v. 90 1729-1739.
  • R. Scott Harris, Michael F. Roden, Paul A. Schroeder, Steven M. Holland, Mack S. Duncan, and Edward F. Albin 2004 An Upper Eocene Impact Horizon in East-Central Georgia, Geology Vol. 32, No. 8, 717–720.
  • Schroeder, P. A., and R. Scott Harris, 2004 X-ray powder diffraction evidence for shocked quartz in an Upper Eocene sand deposit, Warren County, Georgia, U.S.A, Southeastern Geology v. 42(3) 145-150.
  • Schroeder, P. A., Robert J. Pruett and Nathan D. Melear 2004 Crystal-chemical changes in an oxidative weathering front in a middle Georgia kaolin deposit. Clays and Clay Minerals v. 52, 212-220.
  • Schroeder, P. A., Nathan D. Melear and Robert J. Pruett 2003 Quantitative analysis of anatase in Georgia kaolins using Raman spectroscopy Applied Clay Science, v. 23 (5-6) p. 299-308.
  • Ö. Isik Ece, Zenbe-E Nakagawa, and P.A. Schroeder, 2003 Alteration of volcanic rocks and Genesis of kaolin deposits in Sile region, northern Istanbul, Turkey, Part - I: Clay mineralogy, Clay Minerals, v. 51, No. 6, 675-688.
  • Schroeder, P. A., J..J. Le Golvan and M. Roden. 2002 Weathering of ilmenite from granite and chlorite schist in the Georgia Piedmont, USA American Mineralogists. v. 87 (12) 1616-1625.
  • Schroeder, P. A., Melear, N. D., Bierman, P., Kashgarian, M., and Caffee, M., 2001, Gibbsite growth ages for the regolith in the Georgia Piedmont: Geochimca et Cosmochimica Acta, v. 65 (3) p. 381-386.
  • Schroeder, P. A., and Shiflet, J., 2000 Ti-bearing phases in an east Georgia kaolin deposit: Clays and Clay Minerals, v. 48(2) 151-158.
  • Schroeder, P. A., Melear, N. D., West, L. T., and Hamilton, D. A., 2000 Meta-gabbro weathering in the Georgia Piedmont, USA: Implications for global silicate weathering rates: Chemical Geology, v.163, 235-245
  • Schroeder, P. A., and Melear, N. D., 1999 Stable carbon isotopic signatures preserved in authigenic gibbsite from a forested granitic regolith: Panola Mt., Georgia, USA.: Geoderma, p. v 91 p. 261-279.
  • Schroeder, P.A., Pruett, R.J., and Hurst, V.J., 1998 Effects of secondary iron phases on kaolinite 27Al MAS NMR spectra: Clays and Clay Minerals, v. 46(4), 429-435.
  • Schroeder, P.A. and Irby, R. 1998 Detailed X-ray diffraction characterization of illite-smectite from an Ordovician K-bentonite, Walker County, Georgia, USA. Clay Minerals, v. 33, 671-674.
  • Schroeder, P.A., and McLain, A.A., 1998, Illite-smectites and the influence of burial diagenesis on the geochemical cycling of nitrogen: Clay Minerals, v. 33, 539-546.
  • Hurst, V.J., Schroeder, P.A., and Styron, R.W., 1997 Accurate quantification of quartz and other phases by powder x-ray diffractometry: Analytica Chimica Acta, v. 337, 233-252.
  • Schroeder, P. A., Kim, J. G. and Melear, N. D. 1997 Mineralogical and textural criteria for recognizing remnant Cenozoic deposits on the Piedmont: Evidence from Sparta and Greene County, Georgia, U.S.A. Sedimentary Geology. v. 108, 195-206.
  • Schroeder, P.A. and Pruett, R. 1996 Iron ordering in kaolinites: Insights from 29Si and 27Al NMR spectroscopy. American Mineralogist, v. 81, 26-38.
  • Schroeder, P.A. and Ingall E. D. 1994 A method for the determination of nitrogen in clays, with application to the burial diagenesis of shales. Journal of Sedimentary Research, v. A64, 694-697.
  • Schroeder, P.A. 1993 A chemical, XRD and 27Al NMR investigation of Miocene Gulf Coast shales with application to understanding illite/smectite crystal chemistry: Clays and Clay Minerals, v. 41(6). 668-679
  • Schroeder, P.A. 1992 Far infrared study of the interlayer torsional-vibrational mode of mixed-layer illite/smectite. Clays and Clay Minerals. v. 40(1), 81-91.
  • Schroeder, P.A. 1990 Far infrared, X-ray powder diffraction and chemical investigation of potassium micas, American Mineralogist. v. 75, 983-991.
  • Berner, R. A., E. K. Berner, P.A. Schroeder, T. W. Lyons, 1990 Comment and Reply on "Sodium-calcium ion exchange in the weathering of shales: Implications for global weathering budget". Geology v. 18(2), 190.
  • Ingall, E.D., P.A. Schroeder and Robert A. Berner 1990 The nature of organic phosphorus in marine sediments: New insights from 31P NMR. Geochimica et Cosmochimica Acta, v. 54, 2617-2620.
Of note:

Book: Clays in the Critical Zone (expected 2018), Cambridge University Press


A complete grant support list can be found in CV.


Curriculum Vitae:

Seminars by Paul A. Schroeder

G&G Room 200A
Location: Cine (234 Hancock Ave)
Fernbank Science Center
G&G - Room 200A
Geography-Geology Building - Room 200A

Articles Featuring Paul A. Schroeder