和歌山県かつらぎ町・中央構造線断層系近傍における脈動の震動特性

Abstract

Microseisms with period of 1-5 s, observed at Katsuragi-cho, Wakayama Prefecture along a line across the Median Tectonic Line Fault system, exhibit systematic increase of amplitudes in the fracture zone, especially for the vertical and horizontal components parallel to the fault axis (in-plane components), showing the anisotropic amplification effects of fault gauges on seismic waves.Examination of the polarized seismic amplification is important for studying the fault structures as well as the effects of surface geology on seismic waves in the aspect of earthquake engineering.