DUFF, Shamus, Department of Earth Sciences, University of Ottawa, 140 Louis Pasteur Pvt, Ottawa, ON K1N 6N5, Canada, sduff088@uottawa.ca, HANNINGTON, Mark, Department of Earth Sciences, University of Ottawa, Marion Hall, 140 Louis Pasteur Street, Ottawa, ON K1S 0X7, Canada, and MERCIER-LANGEVIN, Patrick, Geologic Survey of Canada, Natural Resources Canada, 490 De la Couronne Street, Quebec, QC G1K 9A9, Canada