HR: 0800h
AN: U11A-0827    [Abstracts]
TI: Field Survey of the 2004 Indonesian Tsunami in Madagascar
AU: * OKAL, E A
EM: emile@earth.northwestern.edu
AF: Northwestern, University, Evanston, IL 60208 United States
AU: Fritz, H M
U11A-0827 AF: Georgia Institute, of Technology, Savannah, GA 31407 United States
AU: Raveloson, R
U11A-0827 AF: Universite, d'Antananarivo, Antananarivo, 101 Madagascar
AU: Joelson, G
U11A-0827 AF: Universite, d'Antananarivo, Antananarivo, 101 Madagascar
AU: Pancoskova, P
U11A-0827 AF: Northwestern, University, Evanston, IL 60208 United States
AU: Rambolamanana, G
U11A-0827 AF: Universite, d'Antananarivo, Antananarivo, 101 Madagascar
AB: We present a report from the work of the International Tsunami Survey Team in Madagascar in the aftermath of the 2004 Sumatra tsunami. During an 11-day campaign, the team surveyed approximately 950 km of coastlines along the Eastern shore of the island, building a database of 52 standardized measurements of flow-depth, run-up and inundation, obtained primarily from eyewitness reports. Maximum heights were found typically on the order of 2 to 4 meters, with an absolute maximum of 5.4 m at the Southernmost tip of the island. In general, the largest values are reported at the extremities of the surveyed area, in the vicinity of Tolagnaro in the South (in a region where one fatality was reported), and of Sambava in the North. By contrast, the central area, in the vicinity of Toamasina, features lower amplitudes, with the tsunami not being observed along a segment of at least 100 km of coastline, around Vatomandry and Manahoro. A most remarkable effect of the tsunami took place in the port of Toamasina, where a 50-m commercial ship broke its moorings and wandered for several hours in the port, carried by powerful eddy currents. This situation is similar to the case of a large container ship in Salalah, Oman (Raad et al., 2005), but the incident in Toamasina occurred around 16:00 GMT, several hours after the arrival of the waves of maximum amplitude. It warrants a reassessment of the evaluation of potential hazards and of mitigation and evacuation procedures for port infrastructures.
DE: 4564 Tsunamis and storm surges
SC: Union [U]
MN: Fall Meeting 2005