GASTALDO, Robert, Department of Geology, Colby College, 5807 Mayflower Hill Drive, Waterville, ME 04901, NEVELING, Johann, Council for Geosciences, Private Bag x112, Silverton, Pretoria, 001, South Africa, GEISSMAN, John, Department of Geosciences, University of Texas at Dallas, 4513 Altura PL NE, Albuquerque, NM 87110, KAMO, Sandra L., Jack Satterly Geochronology Laboratory, Department of Earth Sciences, University of Toronto, 22 Russell Street, Toronto, ON M5S 3B1, Canada and LOOY, Cynthia, Univ. of Calif. BerkeleyDept. of Integrative Biology, 3060 Valley Life Sciences Bldg, Berkeley, CA 94720-3141