ASsudy on the improvement of far-field tsunami waming system

远场海啸预警系统改进研究

基本信息

批准号：
14380205
负责人：
SHUTO Nobuo
金额：
$ 3.78万
依托单位：
Iwate Prefectural Uriversity
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2002
资助国家：
日本
起止时间：
2002 至 2004
项目状态：
已结题

项目摘要

For the improvement of the accuracy of far-field tsunami warning system, we studied (1) Mechanism and characteristics of multiple reflection of tsunamis incident on a continental shelf, (2) An estimation method of tsunami source region by using the real-time observation data, (3) Characteristics of dispersion effect of tsunami during the propagation and run-up process.For the study (1), we derived an analytical solution of tsunamis which are obliquely incident on a offward-finite constant slope. The incident waveforms are assumed to be transient. Based on the solutions obtained, characteristics of transient tsunami propagations on the slope are discussed in terms of the several conditions of incidence such as horizontal incident wave scale, incident angle and incident waveform. When tsunamis are incident almost parallel to the shoreline, multiple reflected waves reveal and are trapped on the slope. The solution indicates that the interference between multiple reflected waves and incoming incident waves could be a contributing cause of conspicuous amplification of tsunamis on the slope.For the study (2), we developed an estimation method for tsunami source region by using the hypothetical offshore tsunami gauge. The method enables to estimate the fault parameters of W and L (Width and Length), which reflects the horizontal extent of tsunami source region, within 20 % of estimation errors.For the study (3), we developed a numerical model with Boussinesq-type equations, which enables to estimate the dispersion effect during the process of tsunami propagation and run-up. The model was validated through the case study of the 1983 Nihonkai-Chubu earthquake tsunami to obtain the better estimate of tsunami height to explain the observed tsunami height along the coast of Japan sea.

为了提高远场海啸警告系统的准确性，我们研究了（1）（1）在大陆架上发生多种海啸的多种反射的机制和特征，（（2）一种海啸源区域的估计方法，使用实时观察数据，（3）在PREPANMI和RUNS的特征效应（3）在Propage和Runive the Pressive and um um up的特征（我们）的特征（我们）研究（1）研究（我们的uniment ofertions of the Pressive。海啸倾向于出现在朝外的恒定斜坡上。假定入射波形是瞬态的。基于获得的溶液，讨论了诸如水平入射波尺度，入射角和入射波形等多种入射率条件（例如，瞬态海啸传播的特征）。当海啸几乎与海岸线平行时，多个反射的波揭示并被困在斜坡上。该解决方案表明，多个反射波与传入的入射波之间的干扰可能是导致海啸在斜坡上明显放大的原因。对于研究（2），我们通过使用假设的海外海岸tsunami量规开发了海啸源区域的估计方法。该方法能够估算W和L（宽度和长度）的故障参数，该方法反映了海啸源区域的水平范围，在估计错误的20％以内（对于研究）（3），我们开发了一个具有Boussinesq-type方程的数值模型，该模型可以估算Tsunami Propagation Propagation and Rugine and Rugin and Rugine and Rugin and Rugin and Rugine and Rugine and Rugin。通过1983年Nihonkai-Chubu地震海啸的案例研究对该模型进行了验证，以获得对海啸高度的更好估计，以解释日本海沿岸观察到的海啸高度。