1. Geological Survey of Canada, 601 Booth Street, Ottawa K1A 0E8, Canada, Geological Survey of Canada, 3303 33rd Street N.W., Calgary T2L 2A7, Canada, Fisheries and Oceans Canada, 501 University Crescent, Winnipeg R3T 2N6, Canada, Canadian Museum of Nature, P.O. Box 3443 Station D, Ottawa K1P 6P4, Canada, and Centre for Earth Observation Science, 474 Wallace Building, University of Manitoba, Winnipeg R3T 2N2, Canada