Seismic hazard analysis depends upon seismology to quantify both the seismic sources that generate seismic waves and the Earth structure through which seismic waves propagate. In this talk, I will present a unified approach for iteratively improving the 3D Earth structure model and seismic source models by solving the elastic/anelastic seismic wave equation using purely numerical methods such as finite-difference. First, I will start with an introduction to the background and motivation, which is primarily focused on ground-motion quantification and prediction. Second, I’ll explain how we can quantify the misfit between model-predicted waveforms and the observed waveforms using time- and frequency-dependent phase-delay and amplitude anomalies and how we can use them to evaluate the quality of a given structural or source model. Third, I will introduce the concept of receiver Green tensor (RGT) and its central role in constructing the partial derivatives needed for near-real-time seismic source parameter inversions and the Fréchet kernels for full-3D waveform tomography. Fourth, I’ll present the results that we have obtained from applying this unified approach to the Los Angeles region. Last, I’ll end my talk with a short discussion of some on-going research and a summary.
5500 Campanile Dr • 237 Geology Mathematics and Computer Science Building • San Diego • CA 92182-1020 • (619) 594-5586
