[1] Department of Geology, St. Francis Xavier University, Antigonish, NS B2G 2W5, Canada
[2] Kennecott Exploration Co., 961 Matley Lane, Suite 120, Reno, NV 89502, United States
[3] Earth Resources Center, Department of Geology and Geophysics, University of California, Berkeley, CA 94720, United States
[4] Department of Earth and Planetary Sciences, McGill University, Montreal, QC H3A 2A7, Canada