We have investigated ground-motion amplification in the Santa Clara Valley (scv) using teleseismic P waves observed during the 1998 deployment of 41 short-period seismometers. The Santa Clara Valley Seismic Experiment (scvse) (Lindh et al., 1999; Fletcher et al., 2003) recorded many local and regional earthquakes and seven large (Mw > 6.4) teleseisms. Measured teleseismic P-wave arrival-time delays, relative P-wave amplification, and P-wave energy were used in the analysis. The relative P-wave amplification is found to correlate strongly with the arrival-time delays. In addition, the P-wave energy is found to correlate with the observed teleseismic delays. We also compared observed P-wave arrival-time delays and P-wave amplification with synthetics computed by using 3D finite-difference simulations of the teleseismic wave field to model these parameters using both the University of California, Berkeley (ucb) (Stidham et al., 1999; Stidham, 1999) and the U.S. Geological Survey (usgs) (Brocher et al., 1997; Jachens et al., 1997) 3D velocity models. The results indicate that arrival-time delays on the order of ±0.25 sec correlate strongly with the reported basin depths in the two models. We find that the correlation between the arrival-time delays and basin depth is strongest for the usgs model. However, the ucb velocity model yields wave amplification that better matches the data. The finite-difference simulations indicate that, in general, the observations may be reproduced by either of the 3D velocity models, although refinements to the proposed 3D structure for the scv are needed.

You do not currently have access to this article.