Tsunami inundation, sediment transport, and subsequent deposits on topography with a dune
Abstract
The processes of tsunami inundation, sediment transport, and subsequent deposits on topography with a dune were investigated as part of Tsunami Sediment Transport Large-scale experiments (TSTLE) project. The inundation process on topography with a dune was categorized into first and second phase flows. The first phase flow was governed by the wave speed at the shoreline and the land slope, whereas the second phase flow was governed by the difference in water level at the dune. The deposits caused by the first phase flow (near the inundation limit) were constant regardless of the presence of the dune. Thus, there was no direct relationship between the substantial erosion and deposition near the dune caused by the second phase flow and the inundation limit determined by the initial phase flow. It is impossible to measure hydraulic parameters beyond these governing parameters from the deposits without assumption of waveform. Therefore, if the inundation limit is determined by the initial phase flow, the only way to reconstruct the inundation limit (height) is to investigate the deposits near the limit. The nearshore deposit, which could be sufficiently thick to observe sedimentary structures, would enable us to estimate the wave level in front of the dune.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2017
- Bibcode:
- 2017AGUFMNH23A0215Y
- Keywords:
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- 3225 Numerical approximations and analysis;
- MATHEMATICAL GEOPHYSICS;
- 4332 Disaster resilience;
- NATURAL HAZARDS;
- 4341 Early warning systems;
- NATURAL HAZARDS;
- 4564 Tsunamis and storm surges;
- OCEANOGRAPHY: PHYSICAL