1Department of Geological Sciences, Northwestern University, Evanston, IL 60208, USA
2Millbrook School, School Road, Millbrook, NY 12545, USA
3Department of Marine Biogeochemistry and Toxicology, Netherlands Institute for Sea Research (NIOZ), P.O. Box 59, 1790 AB Den Burg, Texel, The Netherlands
4Center for Stratigraphy and Paleontology, New York State Museum, The State Education Department, Albany, NY 12230, USA
5College of Marine Science, University of South Florida, St. Petersburg, FL, 33701, USA
6Department of Geological Sciences, University of Missouri, Columbia, MS 65211, USA