1. Geological Hazards Science Center, U.S. Geological Survey, Golden, Colorado 80401, sekbennett@usgs.gov
2. Now at Geology Minerals Energy and Geophysics Science Center, U.S. Geological Survey, Menlo Park, California 94025.
3. Utah Geological Survey, P.O. Box 146100, Salt Lake City, Utah 84114
4. Now at Geological Hazards Science Center, U.S. Geological Survey, Golden, Colorado 80401.
5. Now at Department of Geological Sciences, University of Colorado Boulder, Boulder, Colorado 80309.
6. Luminescence Dating Laboratory, U.S. Geological Survey, Box 25046, MS 974, Denver, Colorado 80225
7. Now at University of Iceland ‐ Háskóli Íslands, Reykjavík, Iceland.