TY - JOUR
T1 - Horizontal and vertical variation of 2004 Indian tsunami deposits
T2 - An example of two transects along the western coast of Thailand
AU - Hori, Kazuaki
AU - Kuzumoto, Ryota
AU - Hirouchi, Daisuke
AU - Umitsu, Masatomo
AU - Janjirawuttikul, Naruekamon
AU - Patanakanog, Boonrak
N1 - Funding Information:
We thank A. Potichan, S. Watana, and T. Norkham for the support of our field survey. Constructive and thoughtful reviews by Witold Szczuciński and an anonymous reviewer are gratefully acknowledged. This study was supported financially by Special Coordination Funds for Promoting Science and Technology.
PY - 2007/4/30
Y1 - 2007/4/30
N2 - We investigated horizontal and vertical variations in modern tsunami deposits along two transects at Nam Khem and Khao Lak, western coast of Thailand, deposited by the large tsunami associated with the earthquake (magnitude 9.0) of 26 December 2004 off Sumatra, Indonesia. Tsunami waves 6-10 m high struck the area approximately 2 h after the earthquake. Tsunami deposits cover the low-lying coastal plains and extend more than 1 km inland from the shoreline. No landward decrease in sediment thicknesses was found clearly at either transect. Terrace scarps and a steep slope behind the coastal plain probably stopped tsunami deposition further inland, causing substantial sediments to be deposited in front of these features. Very clear vertical variations in grain size and multiple layers are found in the deposits to about 600 m inland at Nam Khem. Fine-grained sediments overlie the coarse-grained sediments of the basal layer of the tsunami deposits. At some sites, the fine-grained sediments are overlain by another layer of coarse-grained sediments, suggesting deposits laid down in succession by multiple waves. The basal coarse-grained sediments at Nam Khem fine landward. The up-flow waned inland based on the assumption that the grain size of the basal deposits relates to the strength of the up-flow. These results are potentially useful in disaster prevention and coastal environmental change management as well as for interpreting paleotsunami deposits in geological records.
AB - We investigated horizontal and vertical variations in modern tsunami deposits along two transects at Nam Khem and Khao Lak, western coast of Thailand, deposited by the large tsunami associated with the earthquake (magnitude 9.0) of 26 December 2004 off Sumatra, Indonesia. Tsunami waves 6-10 m high struck the area approximately 2 h after the earthquake. Tsunami deposits cover the low-lying coastal plains and extend more than 1 km inland from the shoreline. No landward decrease in sediment thicknesses was found clearly at either transect. Terrace scarps and a steep slope behind the coastal plain probably stopped tsunami deposition further inland, causing substantial sediments to be deposited in front of these features. Very clear vertical variations in grain size and multiple layers are found in the deposits to about 600 m inland at Nam Khem. Fine-grained sediments overlie the coarse-grained sediments of the basal layer of the tsunami deposits. At some sites, the fine-grained sediments are overlain by another layer of coarse-grained sediments, suggesting deposits laid down in succession by multiple waves. The basal coarse-grained sediments at Nam Khem fine landward. The up-flow waned inland based on the assumption that the grain size of the basal deposits relates to the strength of the up-flow. These results are potentially useful in disaster prevention and coastal environmental change management as well as for interpreting paleotsunami deposits in geological records.
KW - 2004 Sumatra earthquake
KW - Thailand
KW - coastal geomorphology
KW - grain size
KW - tsunami
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U2 - 10.1016/j.margeo.2007.01.005
DO - 10.1016/j.margeo.2007.01.005
M3 - Article
AN - SCOPUS:34047195621
VL - 239
SP - 163
EP - 172
JO - Marine Geology
JF - Marine Geology
SN - 0025-3227
IS - 3-4
ER -