Fig. 5From: Unified approach for evaluation of horizontal site amplification factors with special reference to history of studies on the effects of surface geology on seismic motionObserved HSAF maps at frequencies of 0.5Â Hz and 1.0Â Hz relative to the seismological bedrock based on the GIT by Nakano (2021). Red dotted curves are approximate locations of the Itoigawa-Shizuoka tectonic line. Interpolation is done by GMT (Smith and Wessel 1990)Back to article page