The Tectonic Framework of the Sumatran Subduction Zone

The great Aceh-Andaman earthquake of December 26, 2004 and its tragic consequences brought the Sumatran region and its active tectonics into the world's focus. The plate tectonic setting of Sumatra has been as it is today for tens of millions of years, and catastrophic geologic events have likely been plentiful. The immaturity of our understanding of great earthquakes and other types of geologic hazards contributed to the surprise regarding the location of the 2004 earthquake. The timing, however, is probably best understood simply in terms of the inevitability of the infrequent events that shape the course of geologic progress. Our best hope is to improve understanding of the processes involved and decrease our vulnerability to them.