Abstract
In this paper, we proposed a seismic intensity increment evaluation formula using the
parameters of the fundamental peak of microtremor H/V in order to accurately evaluate seismic
intensity increments even at locations where the exact average S-wave velocity structure is
unknown. First, we derived an approximate expression that simplified the relationship between
the earthquake ground motion spectrum and the seismic intensity increment. Calculated values
and approximate values of seismic intensity increments were estimated for various earthquake
magnitudes and pseudo site amplification effects, and it was shown that these values correspond
well. In addition, it was shown that the seismic intensity increment can be evaluated to some
extent by considering only the fundamental peak of the site amplification effects for the seismic
stations targeted in this study. Next, seismic intensity increments and site amplification effects
were evaluated for seismic stations in the Chugoku region and other areas. We also found an
empirical formula for evaluating seismic intensity increments using the parameters of the
fundamental peak of site amplification effects, and showed that seismic intensity increments can
be evaluated with good accuracy. Finally, we obtained an empirical seismic intensity incremental
evaluation formula using the parameters of the fundamental peak of microtremor H/V. As a result, it was clarified that the seismic intensity increment can be evaluated with good accuracy,
although the prediction accuracy is lower than when using the site amplification effects.
