碩士 / 國立高雄海洋科技大學 / 海洋環境工程研究所 / 95 / In this paper, a multi-grid coupled finite difference numerical model is presented to simulate tsunami generation, propagation and runup in eastern coast of Taiwan. In this model both the linear and the nonlinear versions of the shallow-water equation with different coordinate systems and staggered leap-frog scheme respectively, can be applied to a specific region. The initial profiles of tsunami are determined by parameters of fault below: length of fault = 30km, width of fault = 30km, orientation of fault = N33oE, slip angle = 100o, dip angle = 58o, displacement of fault = 5m, focal depth = 15km, and location of epicenter = 121.83o E / 23.99o N. The model has also been modified so that any ratio of grid size between two adjacent subregions can be combined. To verify the multi-grid coupled finite difference numerical model, two examples are presented and a good agreement between them is observed. The verified model is applied to the Hualien tsunami which occurred on November 15th, 1986. The main features of the propagation of this tsunami which wrap around Taiwan is presented. The tsunami initiated from about 20km offshore Hualien, east of Taiwan. Occuring on the following timeline of 2min, 4min, 6min, 10min, 20min 30min, 40min, 50min and 90min, the leading wave of the tsunami reached first “Hualien,” then “Suao,” “Shihti,” “Chenggon,” “Yonaguni Island,” “Ishigaki Island,” “Iriomote Island,” “Keelung,” “Diaoyu Island,” “Miyako-Jima Island” and “Danshuei,” accordingly. The maximum height of the runups of the tsunami wave in north and east of Taiwan are desbcribed below: “Danshuei = 0.2m,” “Linshanbi = 0.3m,” “Keelung = 0.6m,” “Longdong = 0.5m,” “Suao = 0.7m,” “Hualien = 0.8m,” “Shihti = 0.4m” and “Chenggon = 0.2m,” respectively. Furthermore, the simulated results are compared with the tide-gauge data at Hualien Harbor, Ishigaki Harbor (Ishigaki Island) and Hirara Harbor (Miyako-Jima Island). This data shows that the maximum elevation of the tsunami wave at Hualien Harbor was about 2.0m. A fair agreement is obtained between the dominant period of oscillations in the Hualien Harbor and the arrival time of the first leading wave at Ishigaki Island and Miyako-Jima Isalnd.
In conclusion, this study shows the multi-grid coupled finite difference numerical model enables an accurate simulatioin of the Hualien tsunami. It also demonstrates that the simulated results can be chosen to serve as a reference of regional tsunami warnings in eastern Taiwan.
| Identifer | oai:union.ndltd.org:TW/095NKIMT282003 |
| Date | January 2007 |
| Creators | Shih-Chieh Hsu, 許仕杰 |
| Contributors | Kuo-Tung Chang, 張國棟 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 98 |
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