Affiliation: | U.S. Geological Survey, WRD, 333 W. Nye Ln., Carson City, NV 89706;U.S. Geological Survey, WRD, 6520 Mercantile Way, Lansing. MI 48911;U.S. Geological Survey, WRD, Box 25046, Denver Federal Center, MS 415, Denver, CO 80225-0046;U.S. Geological Survey, WRD, Box 25046, Denver Federal Center, MS 415, Denver, CO 80225-0046 |