1University of Georgia, Athens, USA
2Geological Survey of Canada, Ottawa, Canada
3Institute of Arctic and Alpine Research, University of Colorado, Boulder, USA
4Department of Geology, Syracuse University, Syracuse, USA
5Department of Oceanography, University of Washington, Seattle, Washington, USA
6Computer Unit, Institute of Geological Sciences, London, England
7Department of Geological Sciences, University of Rochester, Rochester, USA
8Department of Geological Sciences, University of Illinois at Chicago Circle, Chicago, USA