Abstract
We simultaneously separate source, propagation path, and site amplification effects from S waves spectra observed at four stations in southern Kanto, Japan. Assuming that observed S waves spectra are combination of source spectra, attenuation along ray path (Qs-1) and site amplification factor, linear inversion method is conducted after transfer of observed S waves spectra into a logarithmic scale. The station in the Kanto Basin but near the Kanto Mountains shows large site amplification factor for high frequency. Qs-1 is proportional to-0.5 power of frequency at 3-20 Hz. We define relatively low- and high-frequency-earthquakes based on the high frequency source spectrum. Depth distribution shows that deep earthquakes are high-frequency-earthquakes at 50-120km in focal depth. Epicenter distribution of low- and high-frequency-earthquakes does not show clear distinguishing characteristics.
