CANNON, William F.1, MILLER, James D.
2, EASTON, Robert Michael
3, NICHOLSON, Suzanne W.
4, WOODRUFF, Laurel G.
5, GREEN, John C.
6, BOERBOOM, Terrence J.
7, WIRTH, Karl R.
8, MCILRAITH, S.J.
9 and WAHL, Timothy E.
7, (1)U.S. Geol Survey, MS 954, Reston, VA 22092, (2)Minnesota Geological Survey, Univ of Minnesota, c/o Natural Resources Research Inst, 5013 Miller Trunk Hwy, Duluth, MN 55811, (3)Ontario Geological Survey, 933 Ramsey Lake Road, Sudbury, ON P3E 6B5, (4)US Geol Survey, 954 National Center, Reston, VA 20192, (5)U.S. Geological Survey, 2280 Woodale Drive, Mounds View, MN 55112, (6)Univ Minnesota - Duluth, Dept Geological Sciences, Duluth, MN 55812-2496, (7)Minnesota Geol Survey, 2642 University Avenue, St. Paul, MN 55114, (8)Geology Department, Macalester College, 1600 Grand Ave, St. Paul, MN 55105, (9)Ontario Geological Survey, 933 Ramsey Lake Road, Sudbury, ON P3E 6B5, Canada, wcannon@usgs.gov, wcannon@usgs.gov