dorsal/arxiv
View SchemaAre Aftershocks of Large Californian Earthquakes Diffusing?
| Authors | Agnes Helmstetter, Guy Ouillon, Didier Sornette |
|---|---|
| Categories | |
| ArXiv ID | physics/0303075 |
| URL | https://arxiv.org/abs/physics/0303075 |
| DOI | 10.1029/2003JB002503 |
| Journal | J. Geophys. Res., 108, 2483, 10.1029/2003JB002503, 2003 |
Abstract
We analyze 21 aftershock sequences of California to test for evidence of space-time diffusion. Aftershock diffusion may result from stress diffusion and is also predicted by any mechanism of stress weakening. Here, we test an alternative mechanism to explain aftershock diffusion, based on multiple cascades of triggering. In order to characterize aftershock diffusion, we develop two methods, one based on a suitable time and space windowing, the other using a wavelet transform adapted to the removal of background seismicity. Both methods confirm that diffusion of seismic activity is very weak, much weaker than reported in previous studies. A possible mechanism explaining the weakness of observed diffusion is the effect of geometry, including the localization of aftershocks on a fractal fault network and the impact of extended rupture lengths which control the typical distances of interaction between earthquakes.
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"abstract": "We analyze 21 aftershock sequences of California to test for evidence of\nspace-time diffusion. Aftershock diffusion may result from stress diffusion and\nis also predicted by any mechanism of stress weakening. Here, we test an\nalternative mechanism to explain aftershock diffusion, based on multiple\ncascades of triggering. In order to characterize aftershock diffusion, we\ndevelop two methods, one based on a suitable time and space windowing, the\nother using a wavelet transform adapted to the removal of background\nseismicity. Both methods confirm that diffusion of seismic activity is very\nweak, much weaker than reported in previous studies. A possible mechanism\nexplaining the weakness of observed diffusion is the effect of geometry,\nincluding the localization of aftershocks on a fractal fault network and the\nimpact of extended rupture lengths which control the typical distances of\ninteraction between earthquakes.",
"arxiv_id": "physics/0303075",
"authors": [
"Agnes Helmstetter",
"Guy Ouillon",
"Didier Sornette"
],
"categories": [
"physics.geo-ph"
],
"doi": "10.1029/2003JB002503",
"journal_ref": "J. Geophys. Res., 108, 2483, 10.1029/2003JB002503, 2003",
"title": "Are Aftershocks of Large Californian Earthquakes Diffusing?",
"url": "https://arxiv.org/abs/physics/0303075"
},
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