| 講演要旨(和文) | | 本研究は，福島県で実施された10点の広帯域リニアアレイ観測の常時微動水平動記録に対し地震波干渉法解析を行った．観測された常時微動水平動記録に対しアレイ観測点間の相互相関関数を算出し，マルチプルフィルタ解析により群速度分散曲線とSN比を推定した． RadialとTransverseの群速度分散曲線をNishidaモデルから期待される群速度理論分散曲線と比較した結果，観測値のほうが群速度が低いことがわかった．また，Takagiの手法を用いてZR，RZの相互相関関数から表面波成分と実体波成分の分離を行い，群速度分散曲線とSN比を推定した．Takagiの手法による表面波とRR，ZZを比較すると，SN比はTakagiの手法の表面波とZZではほぼ同じ値であったが，RRより大きい値が得られた．SN比10以上の周期で群速度を比較すると，3つの群速度はほぼ同程度であり，約2〜3km/sで連続的に分布した． |
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| | 講演要旨(英文) | | The purpose of this research is to perform seismic wave interferometry analysis for microtremor horizontal records of 10 broadband linear array observations made in Fukushima prefecture. The cross correlation functions were calculated for the observed microtremor horizontal records and the group velocity dispersion curves and the SN ratios were estimated by multiple filter analysis. From a comparison of the observed group velocities with calculated ones by Nishida's Vs model, the observed group velocities were smaller than the calculated ones. We tried to distinguish body waves and surface waves by using RZ and ZR cross-correlation functions based on Takagi et al. (2014) method, and the group velocity dispersion curves and the SN ratios were estimated. The SN ratios calculated from surface waves, RR and ZZ were compared. The SN ratios of the surface wave has almost the same value as ones of ZZ, but it was found that the surface wave as a larger value than ones of RR. And three group velocities were calculated and compared. It was found that the three group velocities were almost the same at the periods with the SN ratio of 10 or more and were continuously distributed at about 2-3 km/s. |
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