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IUGG XXIV General Assembly July 2-13, 2007 Perugia, Italy
(S) - IASPEI - International Association of Seismology and Physics of the Earth's
Interior
JSS002 Oral Presentation 1765
Supplementary Post-Tsunami Survey of 2004 Indian Ocean Tsunami in
Sumatra Island and the database
Prof. Koji Fujima
Dept. of Civil and Environmental Eng. National Defense Academy
Indian Ocean Tsunami, occurred on 26 December 2004, caused heavy damages in many countries in
Indian Ocean. After the tsunami, many field investigations were performed to measure the tsunamitrace
height, to examine the damage situation, and to make a suggestion for recovery planning.
However, in Indonesia, the surveys with measurement were concentrated in Banda Aceh city and
northwest part of Sumatra, north of latitude 5.4 degrees N (Lho-nga and Leopung), although the
epicenter was estimated as 3.4 degree N. Therefore, 13 experts organized the survey team and carried
out the supplementary post-tsunami survey from Leopung to Meulaboh, latitude 4.1 degrees N, through
29 July to 6 August, 2006. The length of survey area is 180 km and the number of survey point is about
30. The measured runup height between Leopung and Calang, 100 km south of Banda Aceh, was 13 to
20 m, and the inundation height was 8 to 10 m. As a reference, runup height from Lho-nga and
Leopung (13km length) was 20 to 30 m and the inundation height was 12 to 20 m. Because the lowlying
land lies between Calang and Meulaboh, it was impossible to measure the runup height. However,
the measured inundation height was 3 to 5.5 m, thus the runup height might become round 10 m if
there was a hill in this region. The present survey shows the tsunami height distribution along the
northwest coast of Sumatra. In the present survey area, many big bridges were destroyed by the
tsunami. On the contrary, there were the small bridges which were left without destruction. In addition,
beach erosion is severe between Calang to Meulaboh, the coastline moved over 100 m landward at the
maximum. The mechanism of bridge destruction and beach erosion should be investigated for tsunami
disaster reduction. The database of measurement data of Indian Ocean tsunami was established
including the present data.
Keywords: tsunami, survey, sumatra