1. Department of Earth and Planetary Sciences McGill University Montreal Quebec Canada
2. Now at the Department of Civil and Environmental Engineering Massachusetts Institute of Technology Cambridge MA USA
3. Byrd Polar and Climate Research Centre Ohio State University Columbus OH USA
4. Instituto Geofísico del Perú Lima Peru
5. Department of Earth Sciences University of Minnesota Minneapolis MN USA
6. Saint Anthony Falls Laboratory University of Minnesota Minneapolis MN USA
7. Département de Génie de la Construction École de Technologie Supérieure Montreal Quebec Canada