1. 1EarthScope Consortium (formerly the Incorporated Research Institutions for Seismology), Washington, D.C., U.S.A.
2. 2Antarctic Support Contract/LEIDOS, Centennial, Colorado, U.S.A.
3. 3Department of Earth, Environmental, and Planetary Sciences, Brown University, Providence, Rhode Island, U.S.A.
4. 4Air Force Research Laboratory, Albuquerque, New Mexico, U.S.A.
5. 5Department of Geoscience, Princeton University, Princeton, New Jersey, U.S.A.
6. 6Institut de physique du globe de Paris, CNRS, Université Paris Cité, Paris, France
7. 7Department of Earth and Environmental Sciences, Michigan State University, East Lansing, Michigan, U.S.A.
8. 8U.S. Geological Survey, Geologic Hazards Science Center, Golden, Colorado, U.S.A.