地球の深い地殻の水分化の加速は,ストレスによる干渉によって引き起こされる
B Jamtveit1, H Austrheim, A Malthe-Sørenssen
1Department of Geology, University of Oslo, Norway. bjorn.jamtveit@geologi.uio.no
Nature
|November 18, 2000
まとめ
外部液体は,地球の乾燥した下層地殻の逆転変異に不可欠です. 流体-岩の反応によって引き起こされるストレスフィールドの変化は,岩への流体輸送を加速し,地殻の性質に影響を与えます.
科学分野:
- 地質学 地質学 地質学
- 地質物理学 地質物理学とは地質物理学です.
- テクトニクス (地質学) とは
背景:
- 山のベルトは,最小限の自由流体を持つ下層の地殻を形成します.
- 逆行変形は,乾燥した地殻の体積に外部の液体の導入を必要とする.
- メタモルフィズムによって,地殻の密度やリオロギーなどの物理的性質が大きく変化します.
研究 の 目的:
- 乾燥した地殻岩に流体輸送のメカニズムを調査する.
- 流体-岩の相互作用が,質量輸送にどのように影響するかを理解する.
- 流体移動におけるストレスフィールドの混乱の役割を分析する.
主な方法:
- 変形系における流体岩相互作用のフィールド観測.
- 流体輸送シミュレーションのためのネットワークモデルの開発と応用.
- 異なるストレス条件下での反応フロント形態の分析.
主要な成果:
- 干し岩への流体輸送は,反応によるストレスフィールドの乱れによって加速されます.
- 反応フロントの形態は,外部ストレスフィールドのアニソトロピーに依存しています.
- 質量輸送距離は,単純な穀物境界拡散によって予測される距離を上回る.
結論:
- 流体-岩の反応は,地殻への流体浸透を積極的に強化する.
- 構造的ストレスと流体によって引き起こされるストレス変化は,メタモルフィズムの主な要因です.
- これらのプロセスを理解することは,地殻の進化と性質を解釈するために極めて重要です.
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