UC San Diego

Ground motion prediction plays an important role in seismic hazard analysis. Deterministic wave propagation simulation has proven to be a powerful tool, widely used to predict ground motions in various applications. Recent advances in computing speed and sophistication of numerical methods have allowed ground motion prediction to achieve higher frequencies and broader applicability. However, realistic broadband simulations also require more accurate description of subsurface structure and more complicated physics. Thus, an important question is whether existing velocity models are sufficiently accurate for high frequency simulations. The main objectives of the research presented in this thesis are (1) to examine the efficacy of the current models for accurate ground motion prediction, and (2) if lacking sufficient accuracy, to establish model calibration procedures to deliver more accurate prediction of high-frequency ground motions. The introductory chapter first lays out the specific research questions addressed in this thesis. The following chapters demonstrate the procedure of using seismic data to constrain seismic frequency-dependent attenuation models and near-surface geotechnical layers. Finally, the calibrated models are used to demonstrate that deterministic ground motion simulation in both linear and nonlinear regimes indeed has the potential to be widely used in seismic hazard analysis.