1. Bureau of Reclamation, Denver Federal Center, P.O. Box 25007, Denver, Colorado 80225 U.S.A., jhowe@usbr.gov
2. Department of Geology and Geophysics, University of Utah, 115 S. 1460 East, Room 383, Salt Lake City, Utah 84112‐0101 U.S.A.
3. Department of Geology and Geophysics, University of Utah, 37897 Hood Canal Drive NE, Hansville, Washington 98340 U.S.A.