Study on Formation of Huge Waves due to Landslide in a Reservoir

大约200年前的1792年，日本九州岛岛原半岛的真山发生了一场大滑坡，约15亿泥沙滑入有莱克湾。在这起事件中，山体滑坡产生了类似海啸的巨浪，浪高超过20米，沿海地区有1.45万人死亡。这场灾难是日本最大的灾难之一。在本项目中，建立了基于二维滑坡模型的海啸二维数值模拟模型，并将其应用于Mayuyama灾害。在滑坡体的模拟中，计算结果与滑坡体终止后的实际最终形态、滑坡体的长度和高度基本吻合。在这种情况下，滑坡的信息流可能在触发崩塌后约100s内完成，其速度和厚度分别接近100m/s和30m。在波浪模拟中，通过与模拟结果和观测结果的比较，发现本文所介绍的计算方法很好地再现了滑坡伴随的水位变化。

Almost 200 years ago, in 1792, a big landslide occurred at Mayuyama in Shimabara peninsula, Kyusyu island, Japan About 1.5 hundred millions of sediments slid and flowed into the Ariake Bay. In this case, the huge waves like Tsunami were generated by the landslide and the wave height became more than 20m and 14,500 people were killed in coastal area. This disaster is one at the most huge disaster in Japan. In this project, a two-dimensional numerical simulation model for Tsunami based on two-dimensional landslide model has developed and is applied to Mayuyama disaster. In the simulation of landslide, A result of calculation is closed agree with time actual final shape of the landslide after the termination, the length and the height in the area of Ariake bay. In this case, the phermomena of landslide might finish in about 100sec after the collapse was triggered, and the velocity and the thickness are almost 100m/sec and 30m respectively. And In wave simulation, according to comparison with simulation results and the observed one, it is found how well the calculation method introduced here recreates the change in water level which is accompanied the landslide.