[S-SS15] [JJ] 強震動・地震災害

[SSS15-20] 強震記録を用いたレシーバ関数解析による京都盆地の基盤深度の推定

下村 智也¹、浅野 公之¹、*岩田 知孝¹ (1.京都大学防災研究所)

キーワード：レシーバ関数、京都盆地

We estimated R/V receiver functions of P waveforms of local earthquakes observed at strong motion stations in the Kyoto basin. Assuming a peak time of observed R/V receiver functions corresponds to the difference in arrival time between the direct P wave and the P-to-S converted wave (PS-P time) generated at the sediment/bedrock boundary in the Kyoto basin, we got the basin depth. The present Kyoto basin velocity model (Kyoto Prof., 2006) agreed with the obtained bedrock depth at most stations except several stations located near the basin edge. We modified the bedrock depth beneath each station. For validating that the peak time is corresponding to the PS-P time, we calculated theoretical R/V receiver functions using the discrete wavenumber method (Bouchon, 1981) with a double-couple point source in laterally homogeneous modified velocity model. Theoretical R/V receiver functions using the modified model showed good agreement to the observed R/V receiver functions.