Sediments accumulated in a subduction trench are usually unconsolidated and impede the updip propagation of fault rupture during an earthquake. Seismic images of the southern Sumatra–Andaman trench reveal blocks of consolidated sediment that may have enabled fault rupture in 2004 to propagate up fault dip, thus further seaward, increasing the tsunami magnitude.
- Sean P. S. Gulick
- James A. Austin Jr
- Haryadi Permana
