SEGJ Technical Conference

Influence of 2-D assumption on deep S-wave velocity structure model estimated from waveform inversion

Abstract We conducted numerical experiments for performance of the waveform inversion (Kasamatsu et al., 2015) with different selection of Love wave part in earthquake ground motion records to estimate a 2-D velocity structure of deep sedimentary layers. Synthetic earthquake records were generated from a FDM calculation of a 3D basin model for the Kanto plain in the numerical experiments. When we included the synthetic earthquake records at stations where the 2-D assumption of Love wave propagation was difficult, some parts of the estimated velocity structure were different from the true model. However, the waveform inversion using the earthquake records at stations selected from a 2D assumption criteria proposed by Kasamatsu et al (2016) was able to reproduce an appropriate 2-D velocity structure.