Japan Geoscience Union Meeting 2019

Presentation information

[E] Oral

S (Solid Earth Sciences ) » S-CG Complex & General

[S-CG48] Science of slow earthquakes: Toward unified understandings of whole earthquake process

Thu. May 30, 2019 3:30 PM - 5:00 PM Convention Hall A (2F)

convener:Satoshi Ide(Department of Earth an Planetary Science, University of Tokyo), Hitoshi Hirose(Research Center for Urban Safety and Security, Kobe University), Kohtaro Ujiie(Graduate School of Life and Environmental Sciences, University of Tsukuba), Takahiro Hatano(Earthquake Research Institute, University of Tokyo), Chairperson:Naofumi Aso, Takahiro Hatano

4:00 PM - 4:15 PM

[SCG48-34] Exponential dependence on perturbation stress of earthquake nucleation

*Saito Takuya1, Takahiro Hatano1 (1.The University of Tokyo)

Recent observations have reported that some tremors in slow earthquake are sensitive to stress perturbations caused by ocean tides [1]. According to the preceding studies [1], occurrence frequencies of the susceptible tremors display exponential dependence on the stress magnitude. This study numerically investigates effects on earthquake nucleation growths of the periodic stress perturbations to see if the nucleation developed under the rate-and-state friction law reproduces the stress dependence. The numerical results suggest the exponential dependence on the perturbation stress magnitudes even in the presence of superimposed sinusoidal waves with the different periods. In addition, the exponential rates are found not to be sensitive to a change in the perturbation period or the superposition components of the sinusoidal perturbations, which implies the critical stresses magnitude are independent of a variety of the perturbations.

[1] S. Ide and Y. Tanaka, Geophys. Res. Lett. 41, 3842 (2014); S. Ide, S. Yabe, H.-J. Tai, and K. H. Chen, Geophys. Res. Lett., 42, 3248 (2015).