Stable isotope biogeochemistry

Marine and sedimentary geochemistry


Research Interests

I am a marine/sedimentary geochemist and paleoceanographer with research interests that revolve around the use of stable isotopes and trace metals to understand the marine environment (e.g., oxygenation, productivity, carbon transport and burial) throughout geological time. 

CEOAS Stable Isotope Laboratory

Current Research

My current research is focused on understanding the marine biogeochemistry of silver and how it might be used as a paleoproductivity proxy in marine sediments and rocks.  I am also studying seasonal changes in the isotopic composition of organic matter deposited on the Oregon shelf with a goal of understanding how organic matter accumulates on, and is transported from, the continental shelf. 


Honours BSc, Geology, The University of Western Ontario, London, ON, Canada, 1988
MSc, Geology, The University of Western Ontario, London, ON, Canada, 1992
PhD, Earth and Ocean Sciences, University of British Columbia, BC, Canada, 2004

Professional Memberships

American Geophysical Union (1997 - present)

Geochemical Society (2010 - present)


Praetorius, S.K., Condron, A., Mix, A.C., Walczak, M.H., McKay, J.L., and Du, J. (2020) The role of Northeast Pacific meltwater events in deglacial climate change.  Science Advances, 6 (9).

Cheng, L., Normandeau, C., Bowden, R., Doucett, R., Gallagher, B., Gillikin, D., Kumamoto, Y., McKay, J.L., Middlestead, P., Ninnemann, U. Nothaft, D., Dubinina, E.O., Quay, P., Reverdin, G., Shirai, K., Mørkved, P.T., Theiling, B.P., van Geldern, R., and Wallace, D.W.R. (2019) An international intercomparison of stable carbon isotope composition measurements of dissolved inorganic carbon in seawater. Limnology and Oceanography: Methods, 17, 200-209.

Helser, T., Kastelle, C., McKay, J., Orland, I.J., Kozdon, R., and Valley, J.W. (2018) Evaluation of micromilling/conventional isotope ratio mass spectrometry and secondary ion mass spectrometry of d18O in fish otoliths for sclerochronology.  Rapid Communications in Mass Spectrometry, 32, 1781-1790.

Kastelle, C.R., Helser, T.E., McKay, J.L., Johnston, C.G., Anderl, D.M., Matta, M.E., and Nichol, D.G. (2017). Age validation of Pacific cod (Gadus macorcephalus) using high-resolution stable oxygen isotope (d18O) chronologies in otoliths.  Fisheries Research, 185, 43-53.

Walker, S.A., Azetsu-Scott, K., Normandeau, C., Kelley, D.E., Friedrich, R., Newton, R., Schlosser, P., McKay, J.L., Abdi, W., Kerrigan, E., Craig, S.E., and Wallace, D.W.R. (2016).  Oxygen isotope measurements of seawater (H218O/H216O): A comparison of cavity ring-down spectroscopy (CRDS) and isotope ratio mass spectrometry (IRMS).  Limnology and Oceanography: Methods, 14, 31-38.

Wagner, M., Hendy, I.L., McKay, J.L., and Pedersen, T.F. (2015). Redox chemistry of West Antarctic Peninsula margin surface sediments. Chemical Geology, 417, 102-114.

McManus, J., Severmann, S., Cohen, A.S., McKay, J.L., Poulson Brucker, R.L., Wheatcroft, R., Hartwell, A.M., and Montanye, B.R. (2015). The sedimentary response to a rapid change in lake level in Lake Tanganyika. Palaeogeography, Palaeoclimatology, Palaeoecology, 440, 647-658.

Srain, B., Pantoja, S., Sepúlveda, J., Lange, C., Muñoz, P., Summons, R.E., McKay, J., Salamanca, M. (2015).  Inter-decadal changes in the intensity of the Oxygen Minimum Zone off Concepcion, Chile (~36°S) over the last century.  Biogeosciences, 12, 6045-6058.

McKay, J.L. and Pedersen, T.F. (2014). Geochemical response to pulsed sedimentation: Implications for the use of Mo as a paleo-proxy. Chemical Geology, 382, 83-94.

Marias, D.E., Meinzer, F.C., Woodruff, D.R., Shaw, D.C., Voelker, S.L., Brooks, J.R., Lachenbruch, B., Falk, K., and McKay, J. (2014). Impacts of dwarf mistletoe on the physiology of host Tsuga heterophylla trees as recorded in tree ring C and O stable isotopes.  Tree Physiology, 34, 595-607, doi:10.1093/treephys/tpu046

Bauch, D., Torres-Valdes, S., Polyakov, I., Novikhin, A., Dmitrenko, I., McKay, J., and Mix, A. (2014). Halocline water modification and along slope advection at the Laptev Sea continental margin. Ocean Science, 10, 141-154, doi:10.5194/os-10-141-2014

Saffell, B., Meinzer, R.C., Voelker, S.L., Shaw, D.C., Brooks, J.R., Lachenbruch, B., and McKay, J.  (2014).  Tree-ring stable isotopes record the impact of a foliar fungal pathogen on CO2 assimilation and growth in Douglas-fir.  Plant, Cell & Environment, doi: 10.111/pce.12256

McKay, J.L. and Longstaffe, F.J. (2013). Tracking fluid movement during cyclic steam stimulation of Clearwater Formation oil sands using stable isotope variations of clay minerals.  Clays and Clay Minerals, 61 (5), 440-460.

Wagner, M., Hendy, I.L., McKay, J.L., and Pedersen, T.F. (2013). Influence of biological productivity on silver and redox-sensitive trace metal accumulation in Southern Ocean Surface Sediments, Pacific Sector.  Earth and Planetary Science Letters, 380, 31-40.

Hillaire-Marcel, C., de Vernal, A., and McKay, J. (2011). Foraminifer isotope study of the Pleistocene Labrador Sea, northwest North Atlantic (IODP Sites 1302/03 and 1305), with emphasis on paleoceanographical differences between its "inner" and "outer" basins.  Marine Geology, 279, 188-198.

McKay, J.L. and Pedersen, T.F. (2008). The accumulation of silver in marine sediments: A link to biogenic Ba and marine productivity. Global Biogeochemical Cycles, 22, GB4010, doi:10.1029/2007GB003136.

McKay, J.L., de Vernal, A., Hillaire-Marcel, C., Not, C., Polyak, L., and Darby, D. (2008). Holocene fluctuations in Arctic sea-ice cover: dinocyst-based reconstructions for the eastern Chukchi Sea. Canadian Journal of Earth Sciences, 45 (11), 1377-1397.

Hillaire-Marcel, C., J.-F. Helie, McKay, J., and de Vernal, A. (2008). Elusive isotopic properties of deglacial meltwater spikes into the North Atlantic: example of the final drainage of Lake Agassiz. Canadian Journal of Earth Sciences, 45 (11), 1235-1242.

McKay, J.L., Pedersen, T.F., and Mucci, A. (2007). Sedimentary redox conditions in continental margin sediments (N.E. Pacific) – Influence on the accumulation of redox-sensitive trace metals. Chemical Geology, 238, 180-196.

McKay, J.L., Pedersen, T.F., and Southon, J. (2005). Intensification of the oxygen minimum zone in the northeast Pacific off Vancouver Island during the last deglaciation: Ventilation and/or export production? Paleoceanography, 20, PA4002, doi:10.1029/2003PA000979.

McKay, J.L., Pedersen, T.F., and Kienast, S. (2004). Organic carbon accumulation over the last 16 kyr off Vancouver Island, Canada: Evidence for increased marine productivity during the deglacial. Quaternary Science Reviews, 23, 261-281.

McKay, J.L., and Longstaffe, F.J. (2003). Sulphur isotope geochemistry of pyrite from the Upper Cretaceous Marshybank Formation, Western Interior Basin. Sedimentary Geology, 157, 175-195.

Kienast, S.S and McKay, J.L. (2001). Sea surface temperatures in the Subarctic Northeast Pacific reflect millennial-scale climate oscillations during the last 16 kyrs. Geophysical Research Letters, 28 (8), 1563-1566.

McKay, J.L. and Longstaffe, F.J. (1997). Diagenesis of the Lower Cretaceous Clearwater Formation, Primrose Area, Northeastern Alberta. In: Petroleum Geology of the Cretaceous Mannville Group, Western Canada (eds. Pemberton, S.G. and James, D.P.), Canadian Society of Petroleum Geologists Memoir 18, p. 392-412.

McKay J.L., Longstaffe, F.J., and Plint, A.G. (1995). Early diagenesis and its relationship to depositional environment and relative sea-level fluctuations (Upper Cretaceous Marshybank Formation, Alberta and British Columbia). Sedimentology, 42, 161-190.

McNeil, M. and McKay, J.L. (1994).  Formation of vivianite during microbiologically influenced corrosion of steels.  Scientific Basis for Nuclear Waste Management XVII.  Materials Research Society, 333, 699-704.