Calibrating Median and Uncertainty Estimates for Ground Motion Prediction in Low-to-Moderate Seismicity Region: Application to the Middle Durance Fault (France)

Session: Earthquake Source Parameters: Theory, Observations and Interpretations [Poster]
Type: Poster
Date: 4/30/2020
Time: 08:00 AM
Room: Ballroom
Description: 

In seismic hazard assessment, the definition of the source rupture parameters is a challenging phase for well predicting the ground motion in a low-to-moderate seismicity region. The aim of this study is to calibrate the source rupture parameters for ground motion prediction due to a future earthquake in a low-to-moderate seismicity region. It focuses on the Middle Durance Fault (MDF) close to the CEA nuclear research site of Cadarache (France). While considering a constant magnitude (Mw~6), we analyze more than 1500 kinematic rupture models generated by random sampling of five source rupture parameters: the stress drop, the rupture speed, the nucleation position in both directions (2 parameters) and the geographic location of the rupture on the MDF. For each rupture parameters set, the ground motion indicator at a rock site is calculated using the Empirical Green’s Functions (EGF) technique and is compared to a reference ground motion indicator estimated using empirical ground-motion prediction equations (GMPEs). By using the Monte Carlo Markov Chain (MCMC) method, each ground motion indicator that does not fit the reference value obtained from GMPEs, is screened out and sets of “acceptable” rupture parameter are obtained. Finally, the sediment site response is analyzed using the EGF technique and the accepted rupture parameters sets only.

Presenting Author: Elias El Haber

Authors