| | AbstractRecent earthquakes
have triggered renewed interest to understand better earthquake site
response. Most of the studies comparing various techniques for
estimating site response were based on real data (from earthquakes,
nuclear blasts, and seismic noise). A theoretical approach, using
synthetic data generated with the pseudospectral method, is used to
compare four site-response estimation techniques. The limits of
applicability of each method were determined by modeling microtremors
and incoming SV waves (with different incidence angles) and
analyzing the site amplifications. The first two techniques investigated
consist of dividing the spectrum of the horizontal motion at a site by
that of a reference site using either incident S waves or
microtremors. The latter was unable to reveal either the resonant
frequencies or peak amplitudes in any cases. The two other techniques
are based on the horizontal-to-vertical (H/V) spectral ratio using
S waves or microtremors. These techniques were found to reveal at
least the fundamental resonant frequency and amplitude (former method
only) within 10% error, in the case of simple geology (flat layers).
However, the results show that these techniques are unable to take into
account 2D effects such as focusing effects and basin-edge effects and
yield unreliable or incorrect results in such cases.Return to Table of
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