Feasibility study on the potential of satellite altimetry for detecting seismic geoid changes due to the 2004 Sumatra-Andaman earthquake
© The Society of Geomagnetism and Earth, Planetary and Space Sciences (SGEPSS); The Seismological Society of Japan; The Volcanological Society of Japan; The Geodetic Society of Japan; The Japanese Society for Planetary Sciences. 2007
Received: 22 July 2005
Accepted: 2 October 2007
Published: 30 November 2007
Sea surface height data obtained by satellite altimetry from Jason-1 and TOPEX/Poseidon were analyzed to explore the possibility of a seismic geoid change due to the 2004 Sumatra-Andaman earthquake. This analysis identified a weakly positive geoid change in a region between the trench and outer arc. A subsequent investigation of the characteristics of this coseismic geoid change based on the dislocation theory revealed that a positive peak should indicate the upper edge of the high-slipped area or asperity and that a negative peak is responsible for the lower edge of the earthquake fault. An attempt at modeling the difference in the sea level anomaly failed to explain the observation since a large scatter in the original dataset obstructed its confirmation.