1. University of Texas Institute for Geophysics (UTIG), Austin, TX 78758, USA.
2. Lamont-Doherty Earth Observatory (LDEO), Columbia University, Palisades, NY 10964, USA.
3. Disaster Prevention Research Institute, Kyoto University, Kyoto, Japan.
4. Earthquake Research Institute, University of Tokyo, Tokyo, Japan.
5. Department of Geophysics, Tohoku University, Sendai, Japan.
6. GNS Science, Lower Hutt, New Zealand.
7. Department of Earth and Planetary Sciences, University of California–Santa Cruz, Santa Cruz, CA 95064, USA.
8. Cooperative Institute for Research in Environmental Sciences, University of Colorado–Boulder, Boulder, CO 80309, USA.