JpGU-AGU Joint Meeting 2020

Presentation information

[E] Oral

S (Solid Earth Sciences ) » S-SS Seismology


convener:Luca Urpi, Yusuke Mukuhira(Institute of Fluid Science, Tohoku University), Bogdan Enescu(Department of Geophysics, Kyoto University), Francesco Grigoli(ETH Zurich Swiss Federal Institute of Technology Zurich)

[SSS09-08] Revisiting triggering intensity of earthquakes in southern California using resent seismic catalogs from 2008 to 2017

*Masatoshi Miyazawa1, Emily E Brodsky2, Huiyun Guo2 (1.Disaster Prevention Research Institute, Kyoto University, 2.Department of Earth & Planetary Sciences, University of California Santa Cruz)

Keywords:remote triggering, triggering intensity, southern California

We revisit the systematic increase of local seismicity rate as a function of the amplitude of the transient strain change, using more recent seismic catalogs and data in southern California from 2008 to 2017. The previous studies showed the relationship using data from the Advanced National Seismic System (ANSS) earthquake catalog from 1984 to 2009. For the seismicity in the last decade, a more high-quality seismicity catalog for southern California has been available. We also apply the waveform-based approach to reproduce the triggering ground velocity from the teleseismic events, while a ground motion was previously estimated by using Ms attenuation relationship with the ANSS catalog. These make possible a more precise spatiotemporal estimate of the areas susceptible to remote triggering. The relationship is successfully reproduced using new datasets that are independent of previous studies. In addition, the new method allows us to check a greater range of hypotheses about triggering including the frequency. Furthermore, we examine the temporal changes of the triggering intensity around the 2019 Ridgecrest earthquake area before its occurrence.