Wavelet analysis of the seismograms of the 2004 Sumatra- Andaman earthquake and its application to tsunami early warning
نویسندگان
چکیده
[1] We applied the wavelet transform in an attempt to detect long-period components early in a seismogram. We analyzed the displacement seismograms of the 26 December 2004 Sumatra-Andaman earthquake (Mw = 9.2) and the 28 March 2005 Nias earthquake (Mw = 8.7). Wavelet analysis is able to clearly distinguish the amplitudes of the long-period W phase between the seismograms of the two earthquakes before the S wave reaches the station. It shows that the 2004 earthquake generates a W phase of significantly greater amplitude. This facility has potential application to the rapid identification of truly great earthquakes with high tsunami potential.
منابع مشابه
Seismological Aspects of the December 2004 Great Sumatra-Andaman Earthquake
The 2004 Great Sumatra-Andaman earthquake had an average source duration of about 500 sec. and a rupture length of 1 ,200–1,300 km. The seismic moment, M0, determined with a finite source model, was 6.5 1022 N-m, which corresponds to Mw=9.18. Allowing for the uncertainties in the current M0 determinations, Mw is in the range of 9.1 to 9.3. The tsunami magnitude Mt is 9.1, suggesting that the ov...
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