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Systematic observations of the slip pulse properties of large earthquake ruptures

Diego Melgar·Gavin P. Hayes
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Abstract

In earthquake dynamics there are two end member models of rupture: propagating cracks and self-healing pulses. These arise due to different properties of faults and have implications for seismic hazard; rupture mode controls near-field strong ground motions. Past studies favor the pulse-like mode of rupture; however, due to a variety of limitations, it has proven difficult to systematically establish their kinematic properties. Here we synthesize observations from a database of >150 rupture models of earthquakes spanning M 7– M 9 processed in a uniform manner and show the magnitude scaling properties of these slip pulses indicates self-similarity. Further, we find that large and very large events are statistically distinguishable relatively early (at ~15 s) in the rupture process. This suggests that with dense regional geophysical networks strong ground motions from a large rupture can be identified before their onset across the source region.

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Diego Melgar, Gavin P. Hayes. 2017-10-13. Systematic observations of the slip pulse properties of large earthquake ruptures. https://doi.org/10.1002/2017gl074916

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