[S-SS09] Strong Ground Motion and Earthquake Disaster

[SSS09-P16] A probability-based approach of ground motion estimation using initial P-wave for earthquake early warning

*Zijun WANG¹, Boming ZHAO¹, Hongjun SI² (1.Beijing Jiaotong University, 2.Seismological Reseaerch Institute Inc.)

Keywords:earthquake early warning, ground motion estimation, initial P-wave, Bayesian theorem

Abstract: Earthquake early warning (EEW) system is capable of mitigating and reducing seismic hazards. Although EEW approaches have already been developed worldwide, to improve the accuracy is still very necessary. In this study, we proposed a probability-based method to predicate the site ground motion using the initial P-wave from a single station. Based on the earthquake database at the southwestern area of China provided by the China Strong Motion Net Centre (CSMNC), a total of 489 seismic records with the criteria that magnitude between 3.0 and 7.0 and epicentral distance less than 150 km are analysed. We first investigated several representative characteristic parameters, i.e., the peak measurements and integral quantities, and established the regression relationships to estimate the ground motion parameters. Then by combing those original relationships with the Bayesian theorem, the local priori seismic information was taking into account to further derive an improved estimation model. Finally, aiming at the peak ground acceleration (PGA), the differences between the estimated and actual ones of the combined method and the original method were calculated and compared. Results show that the proposed combined method could yield more accurate estimates of the ground motion and is expected to promote the reliability of an onsite system for EEW.

Acknowledgements: This research has been supported by the NSFC (52272341; U1434210), the NKRDPC (SQ2022YFB2300028) and the FRFCU (2019RC047).