Group features of small seismic waveforms
نویسندگان
چکیده
This paper demonstrates several group features observed from small seismic waveforms and distinguishes abnormal group features that preceded destructive major shocks from normal ones. Important group features discussed in this paper include direction of seismic wave’s first motion, amplitude ratio, half period of the first motion, frequency components of earthquakes, and linearity of seismic waveform. The group features illustrated in this paper have been used as important criteria in earthquake prediction.
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