プレート界面の近くに位置するカスカディア震動は,S マイナス P 波の倍数によって制約されます
Mario La Rocca1, Kenneth C Creager, Danilo Galluzzo
1Istituto Nazionale di Geofisica e Vulcanologia-Osservatorio Vesuviano, Via Diocleziano 328, 80124 Napoli, Italy. mlarocca@ov.ingv.it
まとめ
非火山の振動を特定することは難しい. この研究では,地震波 (S波とP波) のタイムラグを使用して,震動源の深さを正確に特定し,その震動源が潜水板の近くから発生していることを明らかにします.
科学分野:
- 地震学 地震学とは
- 地震研究 地震研究
- テクトニクス (地質学) とは
背景:
- 非火山性震動には明確な地震相がないため,源の位置づけが複雑になります.
- 伝統的な地震ネットワークは,信号の特性により,震動の起源を正確に特定するのに苦労します.
研究 の 目的:
- 非火山の震動源の正確な位置を特定するための新しい方法を開発し,適用する.
- 震源の正確な深さと,地震源とテクトニック構造との関係を決定する.
主な方法:
- 共通の信号を特定するために,縦と横の地震図の交差相関.
- 地震切断波 (S波) と圧縮波 (P波) の間の時間遅れの測定.
- S-Pの時間間隔を位置情報技術と統合して,源の深さを解明する.
主要な成果:
- S-P波の時間間隔は,P波とS波の到着の間の時間を正確に表しています.
- 震源の深さは+/- 2km以内で解明されました.
- 最近のカスカディア地震源は,潜水板の接点またはその近くに位置していました.
結論:
- S-P波の遅延法では,震動源の深さを効果的に解決します.
- カスカディアの震えは,潜水板のインターフェースの近くの繰り返し発生源から発生します.
- このテクニックは,サブダクションゾーンにおける震動過程の理解を深める.
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