The December 26, 2004 magnitude (M) 9.1 Sumatra-Andaman earthquake occurred along a tectonic subduction zone in which the India Plate, an oceanic plate, is being subducted beneath the Burma micro-plate, part of the larger Sunda plate. The boundary between the downgoing and overriding plates of the subduction zone is marked by the Sunda Trench above.

Here we provide a brief overview of the tectonic setting and seismological characteristics of the earthquake, as well as a summary of tsunami generation modeling for this event and the March 28, 2005 M=8.6 northern Sumatra earthquake.