Seismic wave characteristics during large‐scale sediment movement and detection using high‐sensitivity seismic networks

Soichi KAIHARA, Hiroshi ASAHARA, Atsuhiko KINOSHITA, Hiroaki NAKAYA, Yasutaka TANAKA

Abstract

In the event of large‐scale sediment movement, it may be possible to detect seismic waves using a high‐sensitivity seismic network. Use of seismic data to detect large‐scale sediment movement is expected to become a standard disaster monitoring method. This paper systematically presents the results of recent studies on the relationship between large‐scale sediment movement and the characteristics of seismic waves detected by high‐sensitivity seismic networks. We discuss (1) the monitoring position for detection of large‐scale sediment movement, (2) the frequency characteristics of the seismic wave at the time of the sediment movement, (3) the relationship between the type of sediment movement and seismic characteristics, (4) the relationship between underground structures and the likelihood of detection of seismic waves, (5) the relationship between sediment movement and the timing of the increase in wave amplitude, (6) the relationship between the displacement waveform of the extremely low‐frequency wave (0.01-0.1Hz) and sediment movement, and (7) methods for detecting the hypocenter.

Key words

seismic wave, large‐scale sediment movement, seismic characteristics, frequency analysis, detection