1. Department of Earth Sciences, University of Oregon, 100 Cascade Hall, 1272 University of Oregon, Eugene, Oregon 97403‐1272, sequoiaa@uoregon.edu, ray@uoregon.edu
2. Department of Physics, University of Oregon, 120 Willamette Hall, 1371 East 13th Avenue, Eugene, Oregon 97403, dlivelyb@uoregon.edu
3. Department of Earth and Space Sciences, University of Washington, Johnson Hall Room‐070, Box 351310, 4000 15th Avenue NE, Seattle, Washington 98195‐1310, dasc@uw.edu