Roberta L. Rudnick

Professor Roberta Rudnick
Distinguished Professor

Office Hours

by email appointment

Office Location

Webb 1031A


Geochemistry and Petrology, Continent Formation and Evolution




PhD The Research School of Earth Sciences, Australian National University, Canberra, Australia, 1988

MS Sul Ross State University, Alpine, TX, 1983

BS Portland State University, Portland, OR, 1980


Fellow of

  • American Association for the Advancement of Science
  • American Geophysical Union
  • European Association of Geochemistry
  • Geochemical Society
  • Geological Society of America
  • Mineralogical Society of America


  • American Academy of Arts and Sciences
  • National Academy of Sciences

Foreign Associate Chinese Academy of Sciences

Other honors:

  • Bowen Award, VGP section of AGU
  • Dana Medal, MSA
  • Hess Medal, AGU
  • Goldschmidt Medal, Geochemical Society



The geochemistry of glacial diamictites as probes of average upper continental crust composition through time.

Thermochronology of lower crustal xenoliths to constrain Moho temperature and crustal radioactivity.

Testing the relamination hypothesis.

Chalcophile element geochemistry.



Peer Reviewed Papers and Chapters (since 2010)

*graduate student, ** undergraduate student, †post-doc.


Li, W., Nakada, R., Takahashi, Y. Gaschnig, R.M., Hu, Y., Shakouri, M., Rudnick, R.L. and Liu, X-M. (2023) Cerium geochemical composition of the upper continental crust through time: Implications for tracing past surface redox conditions. Geochimica et Cosmochimica Acta 359: 20-29,

Haldar*, U., Chakrabarty, R., Rudnick, R.L. (2023) Enrichment of heavy calcium isotopes in saprolites due to secondary mineral formation. Chemical Geology 637: 121666

Liu, S.-A., Rudnick, R.L., Liu, W.-R., Teng, F.-Z., Wu, T.-H. and Wang, Z.-Z. (2023) Copper isotope evidence for sulfide fractionation and lower crustal foundering in making continental crust. Science Advances 9: eadg6995,

Tian*, S., Ding, X., Qi, Y., Wu, F., Cai, Y., Gaschnig, R.M., Xiao, Z., Lv, W., Rudnick, R.L., Huang F. (2023) Dominance of felsic continental crust on Earth after 3 billion years ago is recorded by vanadium isotopes. PNAS 120: e2220563120,

Johnson, A.C., Zhang, Z.J., Dauphas, N., Rudnick, R.L., Foden, J., Toc**, M. (2023) Redox and mineral controls on Fe and Ti isotopic fractionations during calc-alkaline magmatic differentiation. Geochimica et Cosmochimica Acta 355: 1-12,

Saji, N.S., Rudnick, R.L., Gaschnig, R.M., Millet, M.-A. (2023) Titanium isotope evidence for the high topography of Nuna and Gondwana: Implications for Earth’s redox and biological evolution. Earth and Planetary Science Letters 615: 118214,

Aarons, S.M., Dauphas, N., Greber, N.D., Roskosz, M., Bouchez, J., Carley, T., Liu, X.-M., Rudnick R.L. and Gaillardet, J. (2023) Titanium transport and isotopic fractionation in the critical zone. Geochimica et Cosmochimica Acta 352: 175-193,

Peters, D., Rizo, H., Carlson, R.W., Walker, R.J., Rudnick, R.L. and Luguet, A. (2023) Tungsten in the mantle constrained by continental lithospheric peridotites: Less incompatible and more abundant. Geochimica et Cosmochimica Acta 351: 167-180,

Ringwood*, M.F., Rudnick, R.L., Kylander-Clark, A.R.C. (2023) Metasediments from the lower crust reveal the history of the Picuris orogeny, southwest USA. Geological Society of America Bulletin,

Han*, P.-Y., Rudnick, R.L., He, T., Marks, M.A.W., Wang, S.-J., Gaschnig, R.M., Hu, Z.-C. (2023) Halogen (F, Cl, Br, and I) concentrations of the upper continental crust through time as recorded in ancient glacial diamictite composites. Geochimica et Cosmochimica Acta 341: 28-45,


Apen*, F.A., Rudnick, R.L., Ionov, D.A., Cottle, J.M., Moyen, J.-F., Golovin, A.V. and Korsakov, A.V. (2022) Heat transfer and production in cratonic continental crust: U-Pb thermochronology of xenoliths from the Siberian craton, Geochemistry-Geophysics-Geosystems 23: e2022GC010497,

Liu, X-M., Gaschnig, R.M., Rudnick, R.L., Hazen, R.M., Shahar, A. (2022) Constant iron isotope composition of the upper continental crust over the past 3 Gyr, Geochemical Perspectives Letters 22: 1-4,

Murphy*, M.E., Savage, P.S., Gardiner, J., Prave, A.R., Gaschnig, R.M., and Rudnick, R.L. (2022) Homogenising the upper continental crust: the Si isotope evolution of the crust recorded by ancient glacial diamictites, Earth and Planetary Science Letters 591: 117620,

Gaschnig, R.M., Horan, M.F., Rudnick, R.L., Vervoort, J.D. and Fisher, C.M. (2022) History of crustal growth in Africa and the Americas from detrital zircon and Nd isotopes in glacial diamictites, Precambrian Research 373: 106641,

Wang, Z.-Z., Liu, S.-A., Rudnick, R.L., Teng, F.-Z., Wang, S.-J., and Haggerty, S.E. (2022) Zinc isotope record of carbonate alteration of oceanic crustal protoliths of cratonic eclogites, Earth and Planetary Science Letters 580, 117394


Tian*, S., Moynier, F., Inglis, E., Rudnick, R.L., Huang, F., Chauvel, C., Gaschnig, R.M. Wang, Z., Guo, J. (2021) Zirconium isotopic composition of the upper continental crust through time, Earth and Planetary Science Letters 572: 117086,

Greaney*, A.T., Rudnick, R.L., Romaniello, S.J., Johnson, A.C., Anbar, A.D. and Cummings, M.L. (2021) Assessing molybdenum isotope fractionation during continental weathering as recorded by weathering profiles in saprolites and bauxites, Chemical Geology 566: 120103,


Rudnick, R.L. (2020) The little cation that could, In: (Bowell, R., Pogge von Strandmann, P.A.E., Grew, E., eds.) Lithium: Less is More, Elements 16: 233-234.

Apen*, F.E., Rudnick, R.L., Cottle, J.M., Kyalander-Clark, A.R.C., Blondes, M., Piccoli, P., Seward, G. (2020) Four-dimensional thermal evolution of the East African Orogen: Accessory phase petrochronology of crustal profiles through the Tanzanian Craton and Mozambique Belt, northern Tanzania, Contributions to Mineralogy and Petrology 175: 97

Sun, J., Rudnick, R.L., Kostrovistky, S., Kalashnikova, T., Kitajima, K., Li**, R., Shu, Q. (2020) The origin of low-MgO eclogite xenoliths from Obnazhennaya kimberlite, Siberian Craton. Contributions to Mineralogy and Petrology 175: 25,

Teng, F.-Z., Hu, Y., Ma, J.-L., Wie, G.-J., Rudnick, R.L. (2020) Potassium isotope fractionation during continental weathering and implications for global K isotopes balance. Geochimica et Cosmochimica Acta 278: 261-271

Greaney*, A.T., Rudnick, R.L., Romaniello, S.J., Johnson, A.C., Gaschnig, R.M., and Anbar, A.D. (2020) Molybdenum isotope fractionation in glacial diamictites tracks the onset of oxidative weathering of the continental crust. Earth and Planetary Science Letters 534,

Huang, T.-Y., Teng, F.-Z., Rudnick, R.L., Chen, X.-Y., Hu, Y., Liu, Y.-S., and Wu, F-Y. (2020) Heterogeneous potassium isotopic composition of the upper continental crust. Geochimica et Cosmochimica Acta 278: 122-136

Chen, K., Rudnick, R.L., Wang, Z., Tang, M., Gaschnig, R.M., Zou, Z.-Q., He, T., Hu, Z.-C., Liu, Y.-S. (2020) How mafic was the Archean upper continental crust? Insights from Cu and Ag in ancient glacial diamictites, Geochimica et Cosmochimica Acta 278: 16-29

Li, S.*, Junkin**, W., Gaschnig, R.M., Ash, R.D., Piccoli, P.M., Candela, P.A., and Rudnick, R.L. (2020) Molybdenum content in sulfides in ancient glacial diamictites: implications for Mo delivery to the oceans prior to the Great Oxidation Event, Geochimica et Cosmochimica Acta 278: 30-50

Hanna*, H.D., Liu, X.-M., Park, Y.-R., Kay, S.M., Rudnick, R.L. (2020) Lithium isotopes may trace subducting slab signatures in Aleutian arc lavas and intrusions, Geochimica et Cosmochimica Acta 278: 322-339

Tang, M., Lee, C.-T. A., Rudnick, R.L. and Condie, K.C. (2020) Rapid mantle convection drove massive crustal thickening in the late Archean, Geochimica et Cosmochimica Acta 278: 6-15


Xu*, Y., Tang, W., Hui, H.-J., Rudnick, R.L., Shang, S. and Zhang, Z. (2019) Reconciling the discrepancy between the dehydration rates in mantle olivine and pyroxene during xenolith emplacement, Geochimica et Cosmochimica Acta 267: 179-195,

Wang, S.-J., Rudnick, R.L., Gaschnig, R.M., Wang, H. and Wasylenki, L.E. (2019) Methanogenesis sustained by sulfide weathering during the Great Oxidation Event. Nature Geosciences 12 (3): 296-300;


Mundl, A., Walker, R.J. Reimink, J.R., Rudnick, R.L., Gaschnig, R.M. (2018) Tungsten-182 in the upper continental crust: evidence from glacial diamictites. Chemical Geology 494: 144-152.

Greaney*, A.T., Rudnick, R.L., Gaschnig, R.M., Whalen, J.B., Luias, B., Clemens, J.D. (2018) Geochemistry of molybdenum in the continental crust, Geochimica et Cosmochimica Acta 238: 36-54,

Garber*, J.M., Maurya*, S., Hernandez, J.-A., Duncan, M.S., Zeng, L. Zhang*, H., Faul, U., McCammon, C., Montagner, J.-P., Moresi, L., Romanowicz, B.A., Rudnick, R.L., Stixrude, L. (2018) Multidisciplinary constraints on the abundance of diamond and eclogite in the cratonic lithosphere, G-cubed 19,

Nan*, X.-Y., Yu, H.-M., Rudnick, R.L., Gaschnig, R.M., Xu, J., Li, W.Y., Zhang, Q., Jin, Z.-D., Li, X.-H., Huang, F. (2018) Barium isotopic composition of the upper continental crust, Geochimica et Cosmochimica Acta 233: 33-49,

Chauvel, C. and Rudnick, R.L. (2018) Large-ion lithophile elements, in White, W.M. (editor), Encyclopedia of Geochemistry. Encyclopedia of Earth Sciences Series, Springer, Cham, DOI:

Rudnick, R.L. (2018) Earth’s Continental Crust, in White, W.M. (editor) Encyclopedia of Geochemistry. Encyclopedia of Earth Sciences Series, Springer, Cham, DOI:


Tang*, M., Rudnick, R.L., McDonough, W.F., Bose, M., Goreva, Y. (2017) Multi-mode Li diffusion in natural zircons: evidence for diffusion in the presence of step-function concentration boundaries, Earth and Planetary Science Letters 474: 110-119. DOI:

Greaney*, A.T., Rudnick, R.L., Helz, R.T., Gaschnig, R.M., Piccoli, P.M. and Ash, R.D. (2017) The behavior of chalcophile elements during magmatic differentiation as observed in Kilauea Iki Lava Lake, Hawaii, Geochimica et Cosmochimica Acta 210: 71-96. DOI:

Penniston-Dorland, S., Liu, X.-M. and Rudnick, R.L. (2017) Lithium isotope geochemistry, in (Teng, F.-Z., Watkins, J.M. and Dauphas, N., eds.) Measurements, Theories and Application of Non-Traditional Stable Isotopes, Reviews in Mineralogy and Geochemistry, Mineralogical Society of America 82: 165-217,


Gaschnig, R.M., Rudnick, R.L., McDonough, W.F., Kaufman, A.J., Valley, J., Hu, Z.-C. and Gao, S. (2016) Compositional evolution of the upper continental crust through time, as constrained by ancient glacial diamictites, Geochimica et Cosmochimica Acta 186: 316-343, DOI:

Day, J.M.D., Qiu*, L., Ash, R.D., McDonough, W.F., Teng, F.-Z., Rudnick, R.L. and Taylor, L.A. (2016) High temperature fractionation of Li isotopes in the Moon, Meteoritics and Planetary Science 51 (6): 1046-1062, DOI: 10.1111/maps.12643

Chen*, K., Walker, R.J., Gao, S., Rudnick, R.L., Gaschnig, R.M., Puchtel, I.S., Tang*, M. and Hu, Z. (2016) Platinum group element abundances and Re-Os isotope systematics of the upper continental crust through time: evidence from glacial diamictites, Geochimica et Cosmochimica Acta 191: 1-16,

Tang*, M., Chen*, K., Rudnick, R.L. (2016) Archean upper crust transition from mafic to felsic marks the onset of plate tectonics, Science 351 (6271): 372-375, DOI: 10.1126/science.aad5513.

Li*, S., Gaschnig, R.M. and Rudnick, R.L. (2016) Insights into chemical weathering of the upper continental crust from the geochemistry of ancient glacial diamictites, Geochimica et Cosmochimica Acta 176: 96-117, DOI: 10.1016/j.gca.2015.12.012.


Sauzéat*, L., Rudnick, R.L., Chauvel, C., Garçon, M. and Tang*, M. (2015) New perspectives on the Li isotopic composition of the upper continental crust and its weathering signature, Earth and Planetary Science Letters 428: 181-192, DOI: 10.1016/j.epsl.2015.07.032.

Wang, S.-J., Teng, F.-Z., Rudnick, R.L., Li, S.-G. (2015) A recycled origin for cratonic eclogites: Magnesium isotope evidence in xenolithic eclogites from Sierra Leone, Geology 43: 1071-1074, DOI: 10.1130/G37259.1.

Wang, S.-J., Teng, F.-Z., Rudnick, R.L., Li, S.-G. (2015) Magnesium isotope fractionation during diagenesis and low-grade metamorphism of mudrocks, Geochimica et Cosmochimica Acta 165: 435-448, DOI:

Hui, H.-J., Peslier, A.H., Rudnick, R.L., Simonetti, A., Neal, C.R. (2015) Plume-cratonic lithosphere interaction recorded by water and other trace elements in peridotite xenoliths from the Labait volcano, Tanzania, G-cubed 16:  1687-1710, doi:10.1002/2015GC005779.

Tang*, M., Rudnick, R.L., McDonough, W.F., Huang, Y.* and Gaschnig, R.M. (2015) Europium anomalies constrain recycling of lower continental crust, Geology 43: 703-706, DOI:10.1130/G36641.1.

Liu*, J.-G., Rudnick, R.L., Walker, R.J., Xu, W.-L., Gao, S. and Wu, F.-Y. (2015) Big insights from tiny peridotites: evidence for persistence of Precambrian lithosphere beneath the eastern North China Craton, Tectonophysics 650: 104-112, DOI: 10.1016/j.tecto.2014.05.009

Liu*, X.-M., Wanner, C., Rudnick, R.L. and McDonough, W.F. (2015) Processes controlling d7Li in rivers illuminated by study of streams and ground waters draining basalts, Earth and Planetary Science Letters 409: 212-224, DOI: 10.1016/j.epsl.2014.10.032.

Baptiste*, V., Vauchez, A., Tomassi, A., Demouchy, S., Rudnick, R.L. (2015) Deformation, hydration, and anisotropy of the lithospheric mantle beneath an active rift: constraints from mantle xenoliths from the North Tanzanian Divergence of the East African Rift, Tectonophysics 639: 34-55, DOI:10.1016/j.tecto.2014.11.011.


Gaschnig, R.M., Rudnick, R.L., McDonough, W.F. (2014) Standard addition ICP-MS characterization of selected chalcophile and siderophile elements (Ga, Ge, Mo, Ag, Cd, In, Sn, Sb, W, Tl, and Bi) in USGS whole-rock standard reference materials, Geostandards and Geoanalytical Research 39: 371-379, DOI: 10.1111/j.1751-908X.2014.00330.x.

Rudnick, R.L. and Gao, S. (2014) The Composition of the Continental Crust, pp. 1-51, In: The Crust (2014), R.L. Rudnick, editor, Treatise on Geochemistry, Second Edition, Volume 4, (eds. H.D. Holland and K.K. Turekian), Elsevier-Pergamon, Oxford 805 p.

Tang*, M., Rudnick, R.L. and Chauvel, C. (2014) Sedimentary input to the source of Lesser Antilles lavas: a Li perspective, Geochimica et Cosmochimica Acta 144: 43-58, DOI: 10.1016/j.gca.2014.09.003.

Gaschnig, R.M., Rudnick, R.L., McDonough, W.F., Hu, Z.-C., Gao, S., Kaufman, A.J. (2014) Onset of oxidative weathering of continents recorded in the geochemistry of  ancient diamictites, Earth and Planetary Science Letters 408: 87-99, DOI: 10.1016/j.epsl.2014.10.002.

Liu*, X.-M., Teng, F.-Z., Rudnick, R.L., McDonough, W.F. and Cummings, M.L. (2014) Massive magnesium depletion and isotopic fractionation in weathered basalts, Geochimica et Comsochimica Acta 135: 336-349, DOI: 2014.03.028

Mansur*, A.T., Manya, S., Timpa*, S. and Rudnick, R.L. (2014) Granulite-facies xenoliths in rift basalts of northern Tanzania:  Age, composition and origin of Archean lower crust, Journal of Petrology 55: 1243-1286, doi:10.1093/petrology/egu024.


Teng, F.Z., Yang, W., Rudnick, R.L. and Hu, Y. (2013) Heterogeneous magnesium isotopic composition of the lower crust: a xenolith perspective, G-cubed 14 (9): 3844-3856, DOI: 10.1002/ggge.20238.

Huang*, Y., Chubakov, V., Mantovani, F., Rudnick, R.L. and McDonough, W.F. (2013) Reference Earth model for the heat producing elements and associated geoneutrino flux, G-cubed 14 (6): 2003-2029, DOI: 10.1002/ggge.20129.

Liu*, X.M., Rudnick, R.L., McDonough, W.F. and Cummings, M. (2013) Influence of chemical weathering on the composition of the continental crust: Insights from Li and Nd isotopes in bauxite profiles developed on Columbia River Basalts, Geochimica et Cosmochimica Acta 115: 73-91, http://dx.DOI: 10.1016/j.gca.2013.03.043.


Liu*, J.-G., Carlson, R.W., Rudnick, R.L., Walker, R.J., Wu, F.-Y. and Gao, S. (2012) Comparative Sr-Nd-Hf-Os-Pb isotope systematics of xenolithic peridotites from Yangyuan, North China Craton, Chemical Geology 332-333: 1-14, doi: 10.1016/j.chemgeo.2012.09.013.

Herzberg, C. and Rudnick, R.L. (2012) Formation of cratonic lithosphere: an integrated thermal and petrological model, Lithos 149: 4-15, DOI: 10.1016/j.lithos.2012.01.010.


Liu*, X.M. and Rudnick, R.L. (2011) Constraints on continental crustal mass loss via chemical weathering using lithium and its isotopes, Proceedings of the National Academy of Sciences 108: 20,873-20,880; DOI: 10.1073/pnas.1115671108.

Liu*, J.-G., Rudnick, R.L., Walker, R.J. , Gao, S., Wu, F.-Y., Piccoli, P.H., Yuan, H.L., Xu, W.L., Xu, Y.G. (2011) Mapping lithospheric boundaries using Os isotopes of mantle xenoliths: an example from the North China Craton, Geochimica et Cosmochimica Acta 75: 3881-3902, DOI: 10.1016/j.gca.2011.04.018.

Qiu*, L., Rudnick, R.L., McDonough, W.F. and Bea, F. (2011) The behavior of Li in amphibolite- to granulite-facies rocks of the Ivrea-Verbano Zone, NW Italy, Chemical Geology 289: 76-85, DOI: 10.1016/j.chemgo.2011.07.014.

Aulbach, S., Rudnick, R.L. and McDonough, W.F. (2011) Evolution of the lithospheric mantle beneath the East African Rift in Tanzania and its signatures in rift magmas, In (Beccaluva, L., Bianchini, G. and Wilson, M., eds.) Volcanism and Evolution of the African Lithosphere, Geol. Soc. America Special Paper, p. 105-126.

Bellucci*, J.J., McDonough, W.F. and Rudnick, R.L. (2011) Thermal history and origin of the Tanzanian Craton from Pb isotope thermochronology of feldspars from lower crustal xenoliths, Earth and Planetary Science Letters 301:  493-501, DOI:10.1016/j.epsl.2010.11.031.

Qiu*, L., Rudnick, R.L., Ague, J.J. and McDonough, W.F. (2011) A Li isotope study of sub-greenschist to greenschist facies metamorphism in an accretionary prism, New Zealand, Earth and Planetary Science Letters 301: 213-221, DOI: 10.1016/j.epsl.2010.11.001.

Jochum, K.P., Wilson, S., Abouchami, W., Amini, M., Chmeleff, J., Eisenhauer, A., Hegner, E., Iaccheri, L.M., Kieffer, B., McDonough, W.F., Mertz-Kraus, R., Raczek, I., Rudnick, R.L., Steinhoefel, G., Stoll, B., Stracke, A., Tonarini, S., Weis, D., Weis, U., Woodhead, J.D. (2011) GSD-1G and MPI-DING reference glasses for in-situ and bulk isotopic analysis, Geostandards and Geoanalytical Research 35: 193-226, DOI: 10.1111/j.1751-908X.2010.00114.x.