Investigation of Systematic Ground Motion Effects through Ground Motion Simulation of Small-to-Moderate Magnitude Earthquakes

摘要

This paper presents results of ground motion simulations of small-to-moderate magnitude (3.5≤M_W≤5.0) earthquake events in the Canterbury, New Zealand, region over the past decade, for which centroid moment tensor solutions are available, and an investigation of systematic source and site effects determined via non-ergodic analysis. The simulations are carried out using the Graves and Pitarka methodology with the recently developed 3D Canterbury velocity model. In this study, 144 earthquake ruptures, modelled as point sources, are considered with 1924 quality-assured ground motions recorded at 45 strong motion stations located throughout the Canterbury region. The simulated ground motions, and also empirical prediction equations, are compared with observed ground motions via various intensity measures where the residuals are separated into between-event and within-event components to determine systematic source and site effects. Lastly, the causes of the biases are identified leading to recommendations which could improve the predictive capabilities of the simulation methodology.