1. Department of Earth and Planetary Sciences, University of New Mexico, Albuquerque, New Mexico 87131,USA
2. Earth and Environmental Sciences Division, MS D443, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
3. Department of Geology and Geophysics, University of Wyoming, Laramie, Wyoming 82071-3006, USA
4. Department of Geosciences, Penn State, 336 Deike Building, University Park, Pennsylvania 16802, USA
5. Department of Geography and Center for Integrative Geosciences, University of Connecticut, 354 Mansfield Road U-2045, Storrs, Connecticut 06269, USA
6. Department of Earth and Atmospheric Sciences, 312 Science & Research 1, Houston, Texas 77204-5007, USA
7. Department of Geological Sciences, 1272 University of Oregon, Eugene, Oregon 97403, USA
8. New Mexico Bureau of Geology and Mineral Resources, 801 Leroy Place, New Mexico Tech Socorro, New Mexico 87801, USA
9. 20508 Brimstone Rd., Cedaredge, Colorado 81413, USA
10. Department of Physical and Environmental Sciences, Colorado Mesa University, 1100 North Avenue, Grand Junction, Colorado 81501-3122, USA
11. School of Earth and Space Exploration, P.O. Box 871404, Arizona State University, Tempe, Arizona 85287, USA
12. Geophysical Research Center and Department of Earth and Environmental Science, New Mexico Institute of Mining and Technology, 801 Leroy Place, Socorro, New Mexico 87801, USA
13. Department of Geology, University of Kansas, Lawrence, Kansas 66045-7594, USA
14. Department of Geological Sciences, The University of Texas at Austin, EPS RM 1.130, 1 University Station C9000, Austin, Texas 78712-0254, USA
15. Department of Earth Sciences, Montana State University, P.O. Box 173480, Bozeman, Montana 59717-3480, USA
16. Earth and Environmental Sciences, Lehigh University, 1 West Packer Avenue, Bethlehem, Pennsylvania 18015-3001, USA