Modeling of coastal erosion and sediment deposition during the 2004 Indian Ocean tsunami in Lhok Nga, Sumatra, Indonesia
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This study presents the results of numerical simulations of the 2004 Indian Ocean earthquake and tsunami in the Bay of Lhok Nga (northwestern coast of Sumatra, Indonesia) integrating sediment erosion and deposition. We investigate the transport of sediment both by suspension and by bedload under different scenarii of long breaking dispersive waves through a series of numerical experiments. The earthquake source model used by Koshimura et al. (Coast Eng J 51:243–273, 2008) with a 25-m dislocation better reproduces the wave travel time, flow depth and inundation area than the other models tested. The model reproduces realistically the pronounced coastal retreat in the northern part of Lhok Nga Bay (retreat ranging between 50 and 150 m), where Paris et al. (Geomorphology 104:59–72, 2009) estimated a mean retreat of 80 m. There is also a good agreement between the simulated area of coastal retreat (195,400 m2) and the field observations (203,200 m2). The simulation may underestimate the volume of tsunami deposits (611,700 m3 vs. 500,000–1,000,000 m3 estimated by Paris et al. (2009). The model fully reproduces the observed thickness of tsunami deposits when considering both bedload and suspension, even if bedload transport dominates. Limitations are due to micro-scale topographic, anthropic features (which are not always represented by the DEM) and the amount of debris which may influence flow dynamics and sediment transport.
KeywordsTsunami Dispersive wave Sediment transport Indian Ocean tsunami
This work was funded by French ANR (Agence Nationale de la Recherche) program Risknat—project Maremoti (2008–2012) whose leader is Hélène Hébert (CEA-DASE). The authors are particularly grateful to two anonymous reviewers for their relevant comments. This is Laboratory of Excellence ClerVolc contribution n° 39.
- Choowong M, Murakoshi N, Hisada K, Charoentitirat T, Charusiri P, Phantuwongraj S, Wongkok P, Choowong A, Subsayjun R, Chutakositkanon V, Jankaew K, Kanjanapayont P (2008) Flow conditions of the 2004 Indian Ocean tsunami in Thailand, inferred from capping bedforms and sedimentary structures. Terra Nova 20:141–149CrossRefGoogle Scholar
- Feldens P, Schwarzer K, Szczucinski W, Stattegger K, Sakuna D, Somgpongchaiykul P (2009) Impact of the 2004 Indian Ocean tsunami on seafloor morphology and sediments offshore Pakarang Cape, Thailand. Pol J Environ Stud 18(1):63–68Google Scholar
- Larson M, Wamsley TV (2007) A formula for longshore sediment transport in the swash. Proceedings Coast Sed’07, ASCE, New Orleans: 1924–1937Google Scholar
- Lavigne F, Paris R, Wassmer P, Gomez C, Brunstein D, Grancher D, Vautier F, Sartohadi J, Setiawan A, Gunawan T, Waluyo B, Fachrizal, Mardiatno D, Widagdo A, Cahyadi R, Lespinasse N, Mahieu L (2006) Learning from a major disaster (Banda Aceh, December 26th, 2004): a methodology to calibrate simulation codes for tsunami inundation models. Zeitschrift für Geomorphol Suppl Band 146:253–265Google Scholar
- Lavigne F, Paris R, Grancher D, Wassmer P, Brunstein D, Vautier F, Leone F, Flohic F, De Coster B, Gunawan T, Gomez Ch, Setiawan A, Cahyadi R, Fachrizal (2009) Reconstruction of tsunami inland propagation on December 26, 2004 in Banda Aceh, Indonesia, through field investigations. Pure Appl Geophys 166:259–281CrossRefGoogle Scholar
- Liu PL-F, Woo SB, Cho YS (1998) Computer programs for tsunami propagation and inundation. Technical report, Cornell UniversityGoogle Scholar
- Moore A, Nishimura Y, Gelfenbaum G, Kamataki T, Triyono R (2006) Sedimentary deposits of the 26 December 2004 tsunami on the northwest coast of Aceh, Indonesia. Earth Planet Space 58:253–258Google Scholar
- Paris R, Wassmer P, Sartohadi J, Lavigne F, Barthomeuf B, Desgages É, Grancher D, Baumert Ph, Vautier F, Brunstein D, Gomez Ch (2009) Tsunamis as geomorphic crisis: lessons from the December 26, 2004 tsunami in Lhok Nga, west Banda Aceh (Sumatra, Indonesia). Geomorphology 104:59–72CrossRefGoogle Scholar
- Paris R, Cachao M, Fournier J, Voldoire O (2010b) Nannoliths abundance and distribution in tsunami deposits: example from the December 26, 2004 tsunami Lhok Nga (northwest Sumatra, Indonesia). Géomorphol Relief Process Environ 2010(1):109–118Google Scholar
- Soulsby RL, Smith DE, Ruffman A (2007) Reconstructing tsunami run-up from sedimentary characteristics––a simple mathematical model. Sixth International Symposium on Coastal Processes––coastal sediments’07 coasts, Oceans, Ports and River Institute (COPRI) of the American Society of Civil Engineers, May 13–17, New Orleans, Louisiana Vol. 2, pp 1075–1088Google Scholar
- Tanioka Y, Kasusose T, Kathiroli S, Nishimura Y, Iwasaki S, Satake K (2006) Rupture process of the 2004 great Sumatra—Andaman earthquake estimated from tsunami waveforms. Earth Planet Space 58:203–209Google Scholar