HR: 1340h
AN: S13A-1049 [Abstracts]
TI: Tsunami Field Survey for the Solomon Islands Earthquake of April 1, 2007
AU: * NISHIMURA, Y
EM: yns@mail.sci.hokudai.ac.jp
AF: ISV, Hokkaido University, N10W8, Sapporo, Hokkaido, Sapporo, 060-0810, Japan
AU: TANIOKA, Y
AF: ISV, Hokkaido University, N10W8, Sapporo, Hokkaido, Sapporo, 060-0810, Japan
AU: NAKAMURA, Y
AF: ISV, Hokkaido University, N10W8, Sapporo, Hokkaido, Sapporo, 060-0810, Japan
AU: TSUJI, Y
AF: ERI, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-0032, Japan
AU: NAMEGAYA, Y
AF: AIST, Site C7 1-1-1 Higashi, Tsukuba, 305-8567, Japan
AU: MURATA, M
AF: ADRC, 1-5-2 Wakihama Kaigan Dori, Chuo-ku, Kobe, 651-0073, Japan
AU: WOODWARD, S
AF: Kent State University, OH, Kent, 44242, United States
AB:
Two weeks after the 2007 off-Solomon earthquake, an international tsunami survey team (ITST) of Japanese and
US researchers performed a post tsunami survey in Ghizo and adjacent islands. Main purpose of the team was
to provide information on the earthquake and tsunami to the national disaster council of the Solomon Islands,
who was responsible for the disaster management at that time. The ITST had interview with the affected people
and conducted reconnaissance mapping of the tsunami heights and flow directions. Tsunami flow heights at
beach and inland were evaluated from watermarks on buildings and the position of broken branches and stuck
materials on trees. These tsunami heights along the southern to western coasts of Ghizo Island were ca. 5m
(a.s.l.). Tsunami run-up was traced by distribution of floating debris that carried up by the tsunami and deposited
at their inundation limit. The maximum run-up was measured at Tapurai of Simbo Island to be ca. 9 m. Most of
the inundation area was covered by 0-10 cm thick tsunami deposit that consists of beach sand, coral peaces and
eroded soil. Coseismic uplift and subsidence were clearly identified by changes of the sea level before and after
the earthquake, that were inferred by eyewitness accounts and evidences such as dried up coral reeves. These
deformation patterns, as well as the tsunami height distribution, could constrain the earthquake fault geometry
and motion. It is worthy of mention that the tsunami damage in villages in Ranongga Island has significantly
reduced by 2-3 m uplift before the tsunami attack.
DE: 4564 Tsunamis and storm surges
DE: 7200 SEISMOLOGY
DE: 7299 General or miscellaneous
SC: Seismology [S]
MN: 2007 Fall Meeting