On December 26, 2004, a large (magnitude 9.0) earthquake occurred off the western coast of Sumatra in the Indian Ocean. The earthquake was caused by the release of stresses accumulated as the Burma tectonic plate overrides the India tectonic plate. Movement of the seafloor due to the earthquake generated a tsunami, or seismic sea wave, that affected coastal regions around the Indian Ocean. The northwestern Sumatra coastline in particular suffered extensive damage and loss of life. This astronaut photograph illustrates damage along the southwestern coast of Aceh Province in the vicinity of the city of Lho’ Kruet, Indonesia. Large areas of bare and disturbed soil (brownish gray) that were previously covered with vegetation are visible along the coastline.
On December 26, 2004, tsunamis swept across the Indian ocean, spawned by a magnitude 9.0 earthquake off the coast of Sumatra. Aside from Indonesia, the island nation of Sri Lanka likely suffered the most casualties, with the death toll reported at 21,715 on December 29th.