I would like to thank the Geochemical Society President Rick Carlson, members of the Patterson Award Committee, my colleagues who nominated me for this award, and most especially Yigal Erel who provided a very kind and thoughtful citation. I accept this award on behalf of my entire research group. Without the talented students, postdocs and technicians working together in my laboratory none of our work on mercury isotopes would have been possible. I am deeply honored to be chosen for this award that recognizes the contributions of Clare Patterson to Environmental Geochemistry. Two separate areas of Patterson's research have had a huge influence on my own work. His work on the biopurification of calcium in foodwebs was the basis for a decade of work by my research group on the use of Ca/Sr and Ca/Ba ratios in studies of weathering, catchment hydrology and forest biogeochemistry. And Patterson's work using Pb isotopes to identify anthropogenic Pb in the environment inspired me to work on the development of mercury stable isotope geochemistry.
Before I delve into the topic of mercury stable isotopes I want to take just a few minutes to reflect on some of the scientists who have had the greatest impact on my career. My PhD advisor Jerry Wasserburg taught me how to conduct research and to never shy away from difficult experiments. The late Clare Patterson taught me that the most important research problems in geochemistry relate to human health and the health of ecosystems. My long-time collaborator Yigal Erel helped me make the transition from a cosmochemist and petrologist to an environmental geochemist and convinced me that the tools of high temperature geochemistry had great applicability to environmental science. Finally, my late colleague Jerry Keeler patiently taught me the nitty-gritty details of mercury chemistry, which combined with my isotope geochemistry training, allowed me to make great progress developing mercury stable isotopes as a tool in environmental science.
I was a graduate student at Caltech when Clare Patterson was a very active researcher, but to be honest I failed to take full advantage of the opportunity to benefit from his unique knowledge. It wasn't until my final few years at Caltech that I came to realize how important and creative Patterson's work was. It seems that everyone who knew Patterson has a story about him as the "nutty professor"—and I am no exception. My story involves my citationist, Yigal Erel, learning how to sample soils for lead isotopes in preparation for a trip to the Sierra Nevada Mountains using the clean hands—dirty hands technique. Patterson did not take his new young graduate student to a nearby park or even an out of the way place on the Caltech campus. Instead he had Yigal dig a soil pit on the beautiful manicured lawn in the gardens in front of the Geology and Planetary Science building. A crowd gathered as Patterson yelled profanities every time Yigal deviated from the ideal clean room protocol while sampling soil adjacent to the main pedestrian walkway on campus. This was a perfect example of Patterson's passion for doing things the slow, careful and correct way—and not worrying about what onlookers might think.
Now I have the privilege of spending the next twenty five minutes or so providing an introduction to mercury stable isotopes and explaining a few examples that highlight the great power of mercury isotopes to explore the biogeochemistry and ecology of this important element. I kept the title of my talk very simple and I will try my best to provide a fairly simple presentation to those of you who are not familiar with mercury isotopes. The title of my talk is: "Mass independent isotope fractionation of mercury: why it is such a useful tool in biogeochemistry and ecology."
Joel D. Blum
Earth and Environmental Sciences, University of Michigan
2534 C.C. Little Building, 1100 North University Ave, Ann Arbor, MI 48109-1005
E-mail address: jdblum@umich.edu