11:30 AM - 11:45 AM
[SSS01-10] Numerical shake prediction for Earthquake Early Warning: Introduction of attenuation structure
Keywords:Earthquake early warning, ground motion , real-time , prediction
Recently, innovative approach was proposed for EEW (Hoshiba and Aoki, 2015), that is Numerical Shake Prediction. In the method, the present ongoing wavefield of ground shaking is estimated using data assimilation technique, and then future wavefield is predicted based on physics of wave propagation. Information of hypocentral location and magnitude is not required. Because future is predicted from the present condition, it is possible to address the issue of the non-concentric distribution. Once the heterogeneous distribution is actually monitored in ongoing wavefield, future distribution is predicted accordingly to be non-concentric. We will indicate examples of M6 crustal earthquakes occurred at central Japan, in which strengths of shaking were observed to non-concentrically distribute. We will show their predictions using Numerical Shake Prediction method.
The heterogeneous distribution may be explained by inhomogeneity of attenuation/velocity. If attenuation/velocity structure is introduced, we can predict the future shaking more rapidly and precisely. The information of attenuation/velocity structure leads to more precise and rapid prediction in Numerical Shake Prediction method for EEW. We will show examples of precise predictions of the M6 crustal earthquakes at central Japan using the attenuation structure.