地殻のストレスと損傷は,リッジクレスト断層地帯の地震周期を通して進化します
Jared Bryan1, William B Frank1, Pascal Audet2
1Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA.
まとめ
地震の断裂地帯は 波速の低下が持続しており 蓄積した損傷や永久的な変形を示しています この発見は地震のサイクルダイナミクスと断層地帯の進化の理解に影響を与えます
科学分野:
- 地理学
- 地震学
- テクトノフィジック
背景:
- 地震は断層と地殻の進化によって 築かれた構造的ストレスを放出します
- 地震波の速度は地殻の変形とストレスをモニターしますが,従来の方法は深層の地殻に敏感ではありません.
研究 の 目的:
- 2019年リッジクレスト地震の地震速度とアニソトロピーの変化を調査する.
- 断層地帯の特性に対する地震の長期的影響を理解する.
主な方法:
- 波速とアニソトロピーの変化を追跡するために利用された受信機能.
- 2019年のリッジクレスト地震のデータを分析した.
主要な成果:
- 数ヶ月以内に回復した浅い波の速度減少が観察されました.
- 地震後数年続く 波速の低下を検出しました
- アニゾトロピーの変化も地殻全体で追跡された.
結論:
- 地震後の変形や断層地帯の 永久的な変化による 蓄積された損傷を示唆しています
- これらの発見は,地震サイクルのエネルギー予算と断層地帯の進化を理解するための意味を持っています.
- 2つのシナリオが提案されています. 遅い地震間回復または未成熟の断層地帯の恒久的な変形.
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