Certain trace elements (e.g. Cu, Cr, Zn, Fe, Cd, Ni) serve as essential micronutrients in the oceans, the availability of which influences the physiological state and biochemical activity of marine primary producers. In turn, the consumption of these metals by phytoplankton generally renders changes in their isotopic compositions that can be used to understand a diverse array of biogeochemical processes in the modern oceans.

We also investigate records of trace element isotope compositions in sedimentary archives as proxies of past environmental conditions. In particular, we use and develop isotopic toolkits that can aid in reconstructions of ocean productivity, patterns and rates of ocean circulation, ecosystem community structure, and redox state.

Recent work

  • Probing environmental controls on trace metal incorporation into CaCO3
  • Identification of suitable proxy archives for future trace metal isotopic work
  • Investigating the role of metalloenzymes in controlling isotopic fractionation in microorganisms


Key People



Horner, T.J., R.E.M. Rickaby, and G.M. Henderson (2011) Isotopic fractionation of cadmium into calcite, Earth Planet. Sci. Lett., 312 (1-2), 243-253.

Rehkämper, M., F. Wombacher, T.J. Horner, and Z. Xue (2011) Natural and anthropogenic Cd isotope variations, in Handbook of Environmental Isotope Geochemistry, Adv. Isot. Geochem., vol. 1, edited by M. Baskaran, Springer-Verlag.