Rapid modeling of the 2011 Mw 9.0 Tohoku-oki earthquake with seismogeodesy

Diego Melgar, Brendan W. Crowell, Yehuda Bock, & Jennifer S. Haase

Published June 28, 2013, SCEC Contribution #1934

Rapid characterization of finite fault geometry and slip for large earthquakes is important for mitigation of seismic and tsunamigenic hazards. Saturation of near-source weak motion and problematic integration of strong-motion data into displacements make this difficult in real time. Optimally combining GPS and accelerometer data to estimate seismogeodetic displacement waveforms overcomes these limitations to provide mm-level three-dimensional accuracy and improved rapid estimation of coseismic deformation compared to GPS-only methods. We leverage collocated GPS and accelerometer data from the 2011 Mw 9.0 Tohoku-oki, Japan earthquake by replaying them in simulated real-time mode. Using a novel approach to account for fault finiteness we generate an accurate centroid moment tensor solution independently of any constraint on the slab geometry followed by a finite fault slip model. The replay of GPS and seismic data demonstrates that sufficiently robust models could have been made available within three minutes of earthquake initiation for this event.

Citation
Melgar, D., Crowell, B. W., Bock, Y., & Haase, J. S. (2013). Rapid modeling of the 2011 Mw 9.0 Tohoku-oki earthquake with seismogeodesy. Geophysical Research Letters, 40(12), 2963–2968. doi: 10.1002/grl.50590.