A Study of Implementation Features of the r-Solution Method for Tsunami Source Recovery in the Case of the Illapel Tsunami 2015 Implementation Features of the r-Solution Method

• Published in: Pure and applied geophysics Vol. 178; no. 12; pp. 4853 - 4863
• Main Authors: Voronina, Tatyana A., Voronin, Vladislav V.
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01-12-2021
• Subjects: Earth and Environmental Science; Earth Sciences; Geophysics/Geodesy; waveform inversion; Tsunamis; ill-posed problem; numerical modeling
• ISSN: 0033-4553; 1420-9136
• DOI: 10.1007/s00024-021-02843-7

A methodology is presented for tuning the main parameters of the
r
-solution method as applied to the problem of reconstructing the initial tsunami waveform. Based on singular value decomposition, the
r
-solution method provides an effective means for controlling the instability inherently present in the inverse problem. However, the quality of the inversion depends heavily on the main parameters of the method, which are the number of the right singular vectors which form the basis of a solution space and the number of spatial harmonics used in the tsunami source representation. Unlike previous studies, where these factors were analyzed separately, in this paper they are considered jointly, which allows one to discover the mutual connections between them. The latter makes it possible to improve the inversion results. An optimal number of spatial harmonics decreases the time for matrix calculation and reduces the number of inversion artifacts. The approach for choosing the optimal parameters is illustrated by a case study of the Illapel Tsunami of 2015.