Coastal Morphology Change Before and After 2011 Off the Pacific Coast of Tohoku Earthquake Tsunami at Rikuzen-Takata Coast
Coastal Morphology Change Before and After 2011 Off the Pacific Coast of Tohoku Earthquake Tsunami at Rikuzen-Takata Coast
复制标题
2011年东北地震海啸陆前高田海岸太平洋沿岸前后海岸形态变化
DOI：
10.1142/s0578563416400167
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发表时间：
2016
影响因子：
2.4
通讯作者：
Hitoshi Tanaka
中科院分区：
文献类型：
--
作者：
K. Udo;Yuriko Takeda;Hitoshi Tanaka
本研究调查了2011年东北地震海啸太平洋沿岸前后日本岩手县陆前高田海岸海岸地形的变化以及海岸结构对这些变化的影响。除了海啸期间的航拍视频外，还利用海啸前后的测深数据和航拍照片分析了沿海地形的变化。测深数据是从1989年至2002年建造三座水下防波堤期间以及从2011年海啸之后至2013年获得的。航拍照片是在1947年至2015年期间获得的，航拍视频是在海啸爆发和反冲期间获得的。结果表明，海岸被侵蚀的主要原因是海啸反冲，淹没的防波堤截留了海岸沉积物向海输送。海堤未被冲走的地方部分地防止了侵蚀。沿海结构对沿海海啸的行为和沉积物输送具有显着影响。我们还发现，海啸之后海岸并没有以期望的速度自然恢复，因为海啸之前海岸一直是稳定的。附录中还总结了 2011 年海啸五年后的海岸恢复情况，以说明研究海岸的未来重建计划。
This study investigates the changes in coastal topography of the Rikuzen-Takata Coast in Iwate Prefecture, Japan before and after the 2011 off the Pacific coast of Tohoku Earthquake Tsunami and the effects of coastal structures on these changes. The changes in coastal topography were analyzed using bathymetry data and aerial photographs before and after the tsunami in addition to aerial video during the tsunami. The bathymetry data were obtained from 1989 to 2002 during the construction of three submerged breakwaters and from after the 2011 tsunami until 2013. The aerial photographs were acquired from 1947 to 2015, and the aerial videos were acquired during the tsunami run-up and backwash. The results demonstrated that the coast was eroded mainly due to the tsunami backwash, and the submerged breakwaters trapped the seaward transport of sediment from the coast. Erosion was partly prevented in locations where the seawall was not washed away. The coastal structures had significant effects on the behavior of the coastal tsunami and on sediment transport. We also found that the coast did not recover naturally at the desired speed after the tsunami because the coast had been stable before the tsunami. Coastal restoration five years after the 2011 tsunami are also summarized in the Appendix to illustrate the future reconstruction plan for the study coast.