深層流体,震動,およびサンアンドレアス断層の中央沿いのクリープの間の相関
Michael Becken1, Oliver Ritter, Paul A Bedrosian
1GFZ German Research Centre for Geosciences, Telegrafenberg, 14473 Potsdam, Germany. michael.becken@uni-muenster.de
Nature
|December 2, 2011
まとめ
深い液体はサンアンドレアス断層に移動し,地震活動と断層の強さに影響を与えます. マントルから発生するこの流体流入は,パークフィールドとチョラメの近くの震動と断層の弱さの変動を説明します.
科学分野:
- 地質物理学 地質物理学とは地質物理学です.
- 地震学 地震学とは
- テクトニクス (地質学) とは
背景:
- サンアンドレアス断層は,短い距離で明確な地震パターンを示しています.
- 断層の弱さは,弱い鉱物,高い流体圧,化学的弱化などの要因に起因する.
- 非火山性震動は,深い孔液圧と関連しています.
研究 の 目的:
- サンアンドレアス断層システム内の流体移動を調査するために.
- 流体の存在と震動活動と断層強度の変動を相関させるため.
- 断層の弱体化における深層流体の役割を理解する.
主な方法:
- マグネトテルルリック (MT) データイメージング 電気抵抗性.
- 地物理学的証拠分析. 地物理学的証拠分析.
- 地震による震動と地質学的構造の相関.
主要な成果:
- 地質学的データは,上層マントルからサンアンドレアス断層に流体が移動していることを示しています.
- 震動の横向きの変動は,地殻下部と上部マントルの強さと相関しています.
- 低電気抵抗のゾーンは,相互接続された流体,特にパークフィールド・チョラメの南西を示しています.
- Cholameの近くの液体の蓄積は,高抵抗性のキャップの下に閉じ込められ,震えを集中させます.
- SAFOD付近の垂直の低抵抗性ゾーンは,東部断層ブロックへの深層流体経路を示唆しています.
結論:
- サンアンドレアス断層システムへの深層流体流入が確認されました.
- マントルから発生する液体は震動と断層の強さに影響を与えます.
- 流体移動経路と捕獲メカニズムは,局所的な地震および機械的行動を説明します.
- これは,脆い地殻の高孔圧による流体誘発の断層弱化の仮説を裏付けている.
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