TY - JOUR
T1 - Are inundation limit and maximum extent of sand useful for differentiating tsunamis and storms?
T2 - An example from sediment transport simulations on the Sendai Plain, Japan
AU - Watanabe, Masashi
AU - Goto, Kazuhisa
AU - Bricker, Jeremy D.
AU - Imamura, Fumihiko
PY - 2018
Y1 - 2018
N2 - We examined the quantitative difference in the distribution of tsunami and storm deposits based on numerical simulations of inundation and sediment transport due to tsunami and storm events on the Sendai Plain, Japan. The calculated distance from the shoreline inundated by the 2011 Tohoku-oki tsunami was smaller than that inundated by storm surges from hypothetical typhoon events. Previous studies have assumed that deposits observed farther inland than the possible inundation limit of storm waves and storm surge were tsunami deposits. However, confirming only the extent of inundation is insufficient to distinguish tsunami and storm deposits, because the inundation limit of storm surges may be farther inland than that of tsunamis in the case of gently sloping coastal topography such as on the Sendai Plain. In other locations, where coastal topography is steep, the maximum inland inundation extent of storm surges may be only several hundred meters, so marine-sourced deposits that are distributed several km inland can be identified as tsunami deposits by default. Over both gentle and steep slopes, another difference between tsunami and storm deposits is the total volume deposited, as flow speed over land during a tsunami is faster than during a storm surge. Therefore, the total deposit volume could also be a useful proxy to differentiate tsunami and storm deposits.
AB - We examined the quantitative difference in the distribution of tsunami and storm deposits based on numerical simulations of inundation and sediment transport due to tsunami and storm events on the Sendai Plain, Japan. The calculated distance from the shoreline inundated by the 2011 Tohoku-oki tsunami was smaller than that inundated by storm surges from hypothetical typhoon events. Previous studies have assumed that deposits observed farther inland than the possible inundation limit of storm waves and storm surge were tsunami deposits. However, confirming only the extent of inundation is insufficient to distinguish tsunami and storm deposits, because the inundation limit of storm surges may be farther inland than that of tsunamis in the case of gently sloping coastal topography such as on the Sendai Plain. In other locations, where coastal topography is steep, the maximum inland inundation extent of storm surges may be only several hundred meters, so marine-sourced deposits that are distributed several km inland can be identified as tsunami deposits by default. Over both gentle and steep slopes, another difference between tsunami and storm deposits is the total volume deposited, as flow speed over land during a tsunami is faster than during a storm surge. Therefore, the total deposit volume could also be a useful proxy to differentiate tsunami and storm deposits.
KW - Delft-3D
KW - Numerical simulation
KW - Storm deposit
KW - SWAN
KW - Tsunami deposit
UR - http://www.scopus.com/inward/record.url?scp=85039971578&partnerID=8YFLogxK
UR - http://resolver.tudelft.nl/uuid:9d48ad70-a857-463a-b01d-46fa2f9bbd19
U2 - 10.1016/j.sedgeo.2017.12.026
DO - 10.1016/j.sedgeo.2017.12.026
M3 - Article
AN - SCOPUS:85039971578
SN - 0037-0738
VL - 364
SP - 204
EP - 216
JO - Sedimentary Geology
JF - Sedimentary Geology
ER -