Dynamic high-speed rupture from the onset of the 2004 Parkfield, California, earthquake
Article first published online: 27 FEB 2009
Copyright 2009 by the American Geophysical Union.
Geophysical Research Letters
Volume 36, Issue 4, February 2009
How to Cite
2009), Dynamic high-speed rupture from the onset of the 2004 Parkfield, California, earthquake, Geophys. Res. Lett., 36, L04307, doi:10.1029/2008GL036824., , and (
- Issue published online: 27 FEB 2009
- Article first published online: 27 FEB 2009
- Manuscript Accepted: 27 JAN 2009
- Manuscript Revised: 23 JAN 2009
- Manuscript Received: 27 NOV 2008
- 2004 Parkfield earthquake;
- initial rupture process;
- slip inversion
 We investigated the 2004 Parkfield earthquake using a multiscale slip inversion. The multiscale approach allows us to both focus on the details of the early stages of the rupture process, and to model the entire earthquake at a larger scale. Our model indicates that the Parkfield earthquake began with bilateral high-speed rupture with fast slip rate, up to 4 m/s, and fast propagation velocity of about 3.0 km/s. Rupture propagation to the southeast was arrested 3 s after onset, while propagation to the northwest continued, generated a large slip patch at ∼5 s, and ceased within 10 s. A similar rapid initiation was observed for the 2004 mid-Niigata Prefecture, Japan, earthquake in a previous study. High-speed initial rupture suggests that large earthquakes may initiate and grow in the same way as small earthquakes, and that the final size is difficult to predict from the early stages of an earthquake.