摘要:The 2004 Indian Ocean tsunami and the 2011 Tōhoku earthquake andtsunami caused large-scale topographic changes in coastal areas. Whereasmuch research has focused on coastlines that have or had large humanpopulations, little focus has been paid to coastlines that have little or noinfrastructure. The importance of examining erosional and depositionalmechanisms of tsunami events lies in the rapid reorganization thatcoastlines must undertake immediately after an event. A thoroughunderstanding of the pre-event conditions is paramount to understanding thenatural reconstruction of the coastal environment. This study examines thelocation of sediment erosion and deposition during the 2004 Indian Oceantsunami event on the relatively pristine Phra Thong Island, Thailand.Coupled with satellite imagery, we use numerical simulations and sedimenttransportation models to determine the locations of significant erosion andthe areas where much of that sediment was redeposited during the tsunamiinundation and backwash processes. Our modeling approach suggests thatbeaches located in two regions on Phra Thong Island were significantlyeroded by the 2004 tsunami, predominantly during the backwash phase of thefirst and largest wave to strike the island. Although 2004 tsunami depositsare found on the island, we demonstrate that most of the sediment wasdeposited in the shallow coastal area, facilitating quick recovery of thebeach when normal coastal processes resumed.