Abstract
Strong motion indices such as the instrumental JMA seismic intensity provide important information in earthquake emergency management. Because observed seismic motion is strongly affected by site response characteristics, some estimation procedures are necessary to obtain spatial distributions of these indices. Microtremor observations were conducted at 116 seismic stations in Hyogo prefecture. After confirming that the horizontal-to-vertical (HIV) Fourier spectral ratio of microtremor can express the site response characteristics, a method to estimate the JMA seismic intensity was proposed using the ratio of H/V spectral ratios of microtremor and a strong motion record of the reference station, and its accuracy was compared with other exiting methods.
