| 講演要旨(和文) | | 地震波干渉法の理論に基づいて、著者らは自己相関解析を濃尾平野の地震観測点で取得された強震動記録のSH波に適用した(Watanabe et al., 2011)。本研究では、同じ記録に相互相関解析を適用し、記録の空間密度を向上させることを試みた。近接した2観測点での波形の比較から、波形の相関が低く、相互相関解析の信頼性を低下させていることが明らかとなった。その理由として、設置条件や建造物といった観測点特性の影響が考えられる。この影響は相反定理に基づき相互相関の正負部分を重合することにより低減できる可能性がある。少ない地震記録から反射波を取り出すための重合方法や粗な観測点分布など、S波反射記録合成の問題点について検討した。 |
|
|
| | 講演要旨(英文) | | Based on the theory of seismic interferometry, we have applied the auto-correlation analysis to the SH wave strong-motion records acquired at the seismic stations on the Noubi Plain (Watanabe et al., 2011). We applied the cross-correlation analysis to the same records in order to improve the spatial density of the records. Comparison of the waveform observed at two stations located nearby revealed low correlation between the waveforms, resulting in low reliability of the cross-correlation analysis, possibly due to station characteristics including installation condition and effect of buildings. Stacking causal and anti-causal parts of cross-correlation may reduce this effect. Problems on synthesis of S-wave reflection record, such as stacking strategy to recover the reflection waves from a small number of earthquake records and coarse station distribution, are also discussed. |
|
|
|
| |
|