A splash in Earth gravity from the 2004 Sumatra Earthquake

The 26 December 2004 Sumatra earthquake displaced a large amount of material in the radial direction with respect to the Earth's center, and the earthquake is thus expected to have permanently changed the gravity in a broad region surrounding its causative fault. This article examines gravity changes, which are here quantified by geoid anomaly patterns depicting the displacement of the sea surface's hydrostatic component after the earthquake. The article focuses on the feasibility of the detection of these patterns by gravity space missions. Models of changes in the rotation and oblateness of the Earth due to global gravitational effects of the earthquake have already been reported [Chao and Gross, 2005].