This site is currently in beta, and mobile optimization is currently not in place. Thanks for your patience as we continue to improve the user experience.

Amy M. Gaffney

Portrait of  Amy M. Gaffney

  • Title
    Deputy Group Leader, Chemical & Isotopic Signatures
  • Email
  • Phone
    (925) 422-4396


Amy Gaffney is a geochemist focusing on applications of isotope geochemistry and radiochronometry to nuclear forensics and lunar geochronology. Prior to joining LLNL as a staff member in 2009, she held postdoctoral appointments at the University of New Mexico and LLNL. She is currently the deputy group leader for the Chemical & Isotopic Signatures Group at LLNL, and serves as the principal investigator for projects sponsored by NASA, the Department of Homeland Security, the National Nuclear Security Administration, and DOE-IN.

Gaffney uses mass spectrometry to measure isotope ratios and abundances of a variety of actinides present at ultra-trace levels in environmental samples as well as in bulk nuclear materials. Her research focuses on the use of radiochronometry as a signature of the origin and history of nuclear material. With her current projects, she is developing U-series and Pu-series age-dating signatures of nuclear fuel cycle processes as well as U and Pu production methods. In addition to her research in nuclear forensics, Gaffney also leads research projects that use long-lived isotope chronometers to establish the timing of formation and early differentiation of the moon.

Ph.D., Geological Sciences, University of Washington, Seattle, 2004

M.S., Geological Sciences, University of Washington, Seattle, 1999

B.A., Geology, The Colorado College, 1996

  1. Rolison, J.M., Treinen, K.C., McHugh, K.C., Gaffney, A.M., and Williams, R.W., Application of the 226Ra-230Th-234U and 227Ac-231Pa-235U radiochronometers to uranium certified reference materials, Journal of Radioanalytical and Nuclear Chemistry 314, 2459 (2017).
  2. Borg, L.E., Connelly, J.N., Gaffney, A.M., Cassata, W., and Bizzarro, M., Chronologic implications for slow cooling of troctolite 76535 and temporal relationships between the Mg-suite and the ferroan anorthosite, Geochimica et Cosmochimica Acta. 201, 377 (2017).
  3. Smith, J.A., Andersen, T.J., Shortt, M., Gaffney, A.M., Truffer, M., Stanton, T.P., Bindschadler, R., Dutrieux, P., Jenkins, A., Hillenbrand, C.-D., Ehrmann, W., Corr, H.F.J., Farley, N., Crowhurst, S., and Vaughan, D.G., Sub-ice-shelf sediments record history of twentieth-century retreat of Pine Island Glacier, Nature 541, 77 (2017).
  4. Kristo, M.J., Gaffney, A.M., Marks, N.E., Knight, K., and Cassata, W.S., Nuclear forensic science – Analysis of nuclear material out of regulatory control, Annual Reviews in Earth and Planetary Science 44, 555 (2016).
  5. Gaffney, A.M., Hubert, A., Kinman, W.S., Magara, M., Okubo, A., Pointurier, F., Schorzman, K.C., Steiner, R.E., and Williams, R.W., Round-robin 230Th-234U age dating of bulk uranium for nuclear forensics, Journal of Radioanalytical and Nuclear Chemistry (2015), doi: 10.1007/s10967-015-4334-8.
  6. Borg, L.E., Gaffney, A.M., and Shearer, C.K., A review of lunar chronology revealing a preponderance of 4.34-4.37 Ga ages, Meteoritics and Planetary Science 50, 715 (2014).
  7. Gaffney, A.M. and Borg, L.E., A young solidification age for the lunar magma ocean, Geochimica et Cosmochimica Acta 140, 227 (2014).
  8. Kayzar, T.M., Villa, A.C., Lobaugh, M.L., Gaffney, A.M., and Williams, R.W., Investigating uranium distribution in surface sediments and waters: a case study of contamination from the Juniper Uranium Mine, Stanislaus National Forest, CA, Journal of Environmental Radioactivity 136, 85 (2014).
  9. Elardo, S.M., Shearer, C.K., Fagan, A.L., Borg, L.E., Gaffney, A.M., Burger, P.V., Neal, C.R., and McCubbin, F.M., The origin of young mare basalts inferred from lunar meteorites NWA 4734, NWA 032 and LAP 02205, Meteoritics and Planetary Science 49, 261 (2014).
  10. Keegan, E., Kristo, M.J., Colella, M., Robel, M., Williams, R., Lindvall, R., Eppich, G., Roberts, S., Borg, L., Gaffney, A., Plaue, J., Wong, H., Davis, J., Loi, E., Reinhard, M., and Hutcheon, I., Nuclear forensic analysis of an unknown uranium ore concentrate sample seized in a criminal investigation in Australia, Forensic Science International 240, 111 (2014).
  11. Eppich, G.R., Williams, R.W., Gaffney, A.M., and Schorzman, K.C., 235U-231Pa age dating of uranium materials for nuclear forensic investigations, Journal of Analytical Atomic Spectrometry (2013), doi: 10.1039/c3ja500041a.
  12. Williams, R.W. and Gaffney, A.M., 230Th-234U model ages of some uranium standard reference materials, Proceedings Radiochimica Acta 1, 31 (2011).
  13. Gaffney, A.M., Borg, L.E., Asmerom, Y., Shearer, C.K., and Burger, P.V., Disturbance of isotope systematics in meteorites during shock and thermal metamorphism and implications for shergottite chronology, Meteoritics and Planetary Science 46, 35 (2011).
  14. Borg, L.E., Gaffney, A.M., Shearer, C.K., DePaolo, D.J., Hutcheon, I.D., Owens, T.L., Ramon, E., Brennecka, G., Mechanisms for incompatible element enrichment on the moon deduced from the lunar basaltic meteorite Northwest Africa 032, Geochimica et Cosmochimica Acta 73, 3963 (2009).
  15. Gaffney, A.M., Borg, L.E., and Connelly, J.N., Uranium-lead isotope systematics of Mars inferred from the basaltic shergottite QUE94201, Geochimica et Cosmochimica Acta 71, 5016 (2007).
  16. Gaffney, A.M., Blichert-Toft, J., Nelson, B.K., Bizzarro, M., Rosing, M., and Albarède, F., Constraints on source-forming processes of West Greenland kimberlites inferred from Hf-Nd isotope systematics, Geochimica et Cosmochimica Acta 71, 2820 (2007).
  17. Gaffney, A.M., Borg, L.E., and Asmerom, Y., The origin of geochemical diversity of lunar mantle sources inferred from a combined U-Pb, Rb-Sr and Sm-Nd isotopic study of mare basalt 10017, Geochimica et Cosmochimica Acta 71, 3656 (2007).
  18. Gaffney, A.M., Nelson, B.K., and Blichert-Toft, J., Melting in the Hawaiian plume at 1-2 Ma as recorded at Maui Nui: the role of eclogite, peridotite and source melting, Geochemistry, Geophysics, Geosystems (2005), doi: 10.1029/2005GC000927.
  19. Gaffney, A.M, Nelson, B.K., Reisberg, L., and Eiler, J., Oxygen-osmium isotopic compositions of West Maui lavas: a record of shallow-level magmatic processes, Earth and Planetary Science Letters 239, 122 (2005).
  20. Gaffney, A.M., Nelson, B.K., and Blichert-Toft, J., Geochemical constraints on the role of oceanic lithosphere in intra-volcano heterogeneity at West Maui, Hawaii, Journal of Petrology 45, 1663 (2004).
  21. Gaffney, A.M., Environments of crystallization and compositional diversity of Mauna Loa xenoliths, Journal of Petrology 43, 963 (2002).
  • Secretarial Honor Award, Department of Energy, 2015
  • Outstanding Mentor Award, Department of Energy, Office of Science, 2010
  • Early Career Fellowship, NASA, 2008