Estimating Site Amplification Effects Using Shallow Seismic Data

Shallow Pand SH-wave seismic reflection and refraction data from two sites in the Paducah, Kentucky, area have been used to develop soil column velocity structures in order to estimate site amplification effects resulting from an earthquake. Although the seismic data were of variable quality, numerous reflected and refracted events have been identified and interpreted. Site response modeling, using the computer program WAVES and an acceleration record from the Saguenay, Canada, earthquake, showed that site H-7, near the Paducah airport, experienced amplification of the peak acceleration by a factor of 1.2 at a period of 0.2 s. Site M-l, located near the Ohio River on unconsolidated alluvium, exhibited amplification of the peak acceleration by a factor of nearly 3 at a period of 0.3 s, and the 5% damped acceleration response spectrum shows a peak amplification of over 10 at 0.8 s.