BROWN, Erik T., Large Lakes Observatory & Dept of Geol. Sci, University of Minnesota Duluth, RLB-109, 10 University Drive, Duluth, MN 55812, CABALLERO, Margarita, Instituto de Geofísica, Universidad Nacional Autónoma de México, Ciudad Universitaria, México, 04510, Mexico, FAWCETT, Peter J., Earth and Planetary Sciences, University of New Mexico, 220 Northrop Hall, Albuquerque, NM 87131, LOZANO, Socorro, Departamento de Paleontología, Instituto de Geología, Universidad Nacional Autónoma de México, Cd. Universitaria, Mexico City, 04510, Mexico, ORTEGA, Beatriz, Instituto de Geofisica, Universidad Nacional Autónoma de México, Ciudad Universitaria, México, 04510, Mexico, SCHWALB, Antje, Institut für Umweltgeologie, Technische Universität Braunschweig, Braunschweig, 38106, Germany, SMITH, Victoria C., Research Laboratory for Archaeology and the History of Art, University of Oxford, Oxford, OX1 3QY, STEINMAN, Byron A., Large Lakes Observatory and Department of Earth and Environmental Sciences, University of Minnesota Duluth, 2205 E. 5th Street RLB 205, Duluth, MN 55812, PEREZ, Liseth C., Instituto de Geología, Universidad Nacional Autónoma de México, Distrito Federal, 04510, Mexico, STOCKHECKE, Mona, Swiss Federal Institute of Technology (ETH), Zurich, 8200, Switzerland, VALERO-GARCES, Blas Lorenzo, Pyrenean Institute of Ecology, Spanish National Research Council, Avda Montañana 1005, apdo 13034, Zaragoza, 50080, Spain, WATT, Sebastian, Geography, Earth and Environmental Sciences, University of Birmingham, Birmingham, B15 2TT, United Kingdom and WONIK, Thomas, Leibniz Institute for Applied Geophysics (LIAG), Hannover, D-30655, Germany, etbrown@d.umn.edu