The 2015 Illapel Tsunami Source Recovery by Inversion of DART Tsunami Waveforms Using the R-Solution Method
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An approach to recovering an initial tsunami waveform with its application to the 16 September 2015 Illapel tsunami is proposed. The approach is based on inverting the remote measurements of water-level data from the deep-ocean DART buoys without a priori information on a source except for the common information about its spatial localization. The ill-posed inverse problem in question is regularized by means of a least-squares inversion using the truncated singular value decomposition method and the r-solution method. The method proposed suppresses the instability of the numerical solution of the ill-posed problem under consideration. The computational algorithm allows one to find the way to improve the inversion by selecting the most informative set of available observation stations. The method proposed was successfully applied to the 16 September 2015 Illapel tsunami.
KeywordsTsunami numerical simulation tsunami waveform inversion ill-posed inverse problem singular value decomposition r-solution
The authors thank Artem Loskutov, Ph.D., from the Institute of Marine Geology and Geophysics Far Eastern Branch Russian Academy of Science, for his assistance in the preparation of data, and Aleksei Romanenko, Ph.D., from Novosibirsk State University for his assistance in arranging calculations. The research proposed was made under the State Budget Program no. 0315-2016-0005.
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