| 講演要旨(和文) | | 笠松ほか(2015)によるラブ波を用いた深部地盤の二次元速度構造推定法について，波形インバージョンで対象とする地震観測記録を変える影響を調べるための数値実験を行った．関東平野の三次元盆地構造モデルを用いた差分法により，模擬地震動データを作成した．ラブ波伝播の二次元仮定に矛盾がある地点の観測記録をインバージョンに含めると，一部の場所で正解とは異なる速度構造が推定された．一方，笠松ほか(2016)の基準に基づき，二次元仮定が妥当と考えられる地点の観測記録のみをインバージョン対象とすることで，正解の二次元速度構造を再現する結果が得られた． |
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| | 講演要旨(英文) | | 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. |
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