Complete Implementation of the Green's Function Based Time Reverse Imaging and Sensitivity Analysis of Reversed Time Tsunami Source Inversion. Issue 19 (5th October 2017)

• Record Type: Journal Article
• Authors: Hossen, M. J.; Cummins, P. R.; Satake, K.
• Is Part Of: Geophysical research letters. Volume 44:Issue 19(2017)
• Page Start: 9844
• Page End: 9855
• Publication Date: 2017-10-05
• Subjects: tsunami source inversion -- time reverse imaging -- complete GFTRI -- sensitivity analysis; Geophysics -- Periodicals; Planets -- Periodicals; Lunar geology -- Periodicals; 550
• DOI: 10.1002/2017GL074528
• Languages: English
• ISSNs: 0094-8276

Abstract

Abstract: In recent studies, the Time Reverse Imaging (TRI) method has been implemented in tsunami science to estimate tsunami source models. A TRI algorithm called Green's Function Based Time Reverse Imaging (GFTRI) was previously developed to reconstruct the source model by using source inversion as a guide to appropriately scale time‐reversed images of the tsunami source. In this article, we consider a more complete approach to source inversion using reversed time images of the tsunami source by considering cross correlations among Green's functions. As a consequence, the performance of the method improves significantly. We tested this new algorithm using data from the 2011 Japan tsunami. Our results show that the method is capable of extracting more details of the source and providing excellent waveform fits at all stations, including those not used in the source imaging. We have also studied the sensitivity analysis of reversed time tsunami source inversion and found that the method is less sensitive to the number of stations, once a minimum number of stations is utilized. Moreover, this new approach is able to estimate the tsunami source with reasonable accuracy using data available soon after an earthquake, which indicates that it has potential to be used in both near‐ and far‐field tsunami forecasting. Key Points: Significant improvement of the Green's Function Based Time Reverse Imaging is made by considering cross‐correlations among Green's functions This new approach is capable of estimating the tsunami source with more details and providing excellent waveform agreement Sensitivity analysis has been studied to understand the effect of number of stations and duration of recordings in source inversion