HR: 0800h
AN: U51A-0012    [Abstracts]
TI: The Sumatra September 2007 Sequence of Large Earthquakes and Tsunami Warning
AU: * Hsu, V
EM: vindell.hsu@noaa.gov
AF: Pacific Tsunami Warning Center, 91-270 Ft. Weaver Rd., Ewa Beach, HI 96706,
AB: The Sumatra sequence of large earthquakes in September 2007 started on 12 September with three earthquakes of magnitudes 8.4, 7.9 and 7.1 occurring within 15 hours along a stretch of the Sumatra coastline about 500 km long. The M 8.4 event generated a small tsunami of about 1 m at the nearby city of Padang. The damage was more from the earthquake shaking than from tsunamis. The three earthquakes acted as three main shocks ruptured three parts of the Sunda Arc. Each has its own aftershocks. The three aftershock areas add to be about equivalent to the size of the aftershock area of the March 28, 2005 Simeuleu-Nias earthquake of M 8.7 to the north of this area. Before this sequence and after the December 2004 M 9.2 Sumatra earthquake, there were also the March 28, 2005 M 8.7 Simeuleu-Nias earthquake and the July 17, 2006 M 7.7 Java earthquake. Based on the high seismicity of large earthquakes, many believe that more "big" ones are likely. This study attempts to analyze the seismicity and characters of each of the large earthquakes using seismic arrays. Results will be presented.
DE: 7230 Seismicity and tectonics (1207, 1217, 1240, 1242)
DE: 7240 Subduction zones (1207, 1219, 1240)
SC: Union [U]
MN: 2007 Fall Meeting