U.S. Geological Survey, 345 Middlefield Rd., Menlo Park, CA 94025 United States
Department of Geosciences Department of Geosciences, Gould-Simpson Building University of Arizona, Tucson, AZ 85721 United States
Department of Geosciences Department of Geosciences, Gould-Simpson Building University of Arizona, Tucson, AZ 85721 United States
Department of Geosciences Department of Geosciences, Gould-Simpson Building University of Arizona, Tucson, AZ 85721 United States
Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology 79 Massachusetts Ave., Cambridge, MA 02139 United States