Variation in Ground Shaking on the Fraser River Delta (Greater Vancouver, Canada)

We have utilised recordings of recent moderate (1996 M=5.1 at 180 km distance, 1997 M=4.3 at 40 km distance) and large (2001 M=6.8 at 230 km distance) earthquakes to examine site response in the greater Vancouver, region, with an emphasis on the Fraser River delta. These suites of accelerograms have relatively low amplitudes ( 0.015g for the 1996 records, 0.024g for the 1997 records, and 0.035g for the 2001 records). The 1997 data set is significant as it contains the first three-component recordings made on bedrock in greater Vancouver, and the 2001 data set is significant as it contains longer-period energy. We compute spectral ratios to estimate the site response for each of the soil sites.

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