.This is a proposal to understand better the Sunda subduction megathrust, whose rupture produced the giant earthquakes of late 2004 and early 2005 along the western coast of Sumatra. During the 3-year grant period the researchers will investigate the short- and long-term behavior of the Sumatran sections of these great ruptures, using records of vertical deformation contained in coral microatolls. The principal reason for deciphering an extended history of inter- and co-seismic motions on this active fault is to promote a more complete understanding of the mechanics of cyclic strain accumulation and relief. The records will span not only the months before and after the recent giant earthquakes, but also prior decades and centuries, including 1861 and 1907, the dates of two prior large tsunamigenic earthquakes. Significant non-scientific aspects of the work are hazard mitigation and educational activities precipitated by the realization that dangerous, giant earthquakes and tsunamis occur along the Sumatran west coast. The PIs will continue to create educational posters and brochures based upon our Sumatran discoveries and distributing them by the thousands to West and North Sumatran villagers and American and Australian surfers. They also intend to enhance existing middle and high school Earth science curricula with scientific content that incorporates recent and/or new findings as a result of this research.
