Short-period Spectral Level, Path and Site-amplification Derived from Strong Motion Records during the Normal-faulting Earthquakes in Hamadori, Fukushima Prefecture in 2011

Abstract

We estimate the short-period spectral level A of the normal-faulting earthquakes in Hamadori, Fukushima prefecture in 2011 using the spectral inversion method. The A of M_J7.0(M_w6.6) earthquake is consistent with the average empirical relation between the seismic moment and A for crustal earthquakes. The PGA and PGV of this earthquake corrected by empirical site-amplification factor at each strong motion station agree with the average empirical attenuation relation for crustal earthquakes in Japan. The high area of the fault-normal to fault-parallel ratios of response spectra at 5 second of the normal-faulting earthquakes is longer than that of reverse-faulting earthquakes due to the domination of Rayleigh waves.