1. Environmental Sciences Group, Royal Military College, Kingston, Ontario K7K7B4, Canada, Department of Geological Sciences and Geological Engineering, Queen’s University, Kingston, Ontario K7L3N6, Canada, British Geological Survey, Keyworth, Nottingham NG125GG, United Kingdom, and Natural Resources Canada, Geological Survey of Canada (Atlantic), 1 Challenger Drive, Dartmouth, Nova Scotia B2Y4A2, Canada