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Estimation of Seismic Wave Coherency and Rupture Velocity Using the SMART 1 (Strong Motion Array Taiwan, Number 1) Strong-Motion Array Recordings.
Abrahamson, N. A.
National Science Foundation, Washington, DC., March 1985, 141 p.
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The January 29, 1981 Taiwan earthquake (M sub L = 6.7) was recorded digitally by 27 triaxial force-balanced accelerometers in the SMART 1 strong motion array centered 30 km north-northwest of the epicenter. The seismic source of this event had a reverse mechanism with unilateral rupture from east to west. The array recordings are used to make direct measurements of the wave coherency and the time dependent rupture velocity. Frequency-wavenumber analysis shows that across the 4 km array, the P waves contain coherent energy from the source region at frequencies up to 6 Hz while the S waves contain coherent energy up to 3 Hz. Significant energy is present in the P and S waves at frequencies above these two levels, but it is incoherent or scattered energy.
Taiwan; Seismic waves; Bursting; Smart 1; Seismic epicenter; Earthquake engineering; Velocity; Coherence; Seismic effects; Earthquakes