海底の面積と年齢の関係に関するダイナミックな原因
N Coltice1, T Rolf, P J Tackley
1Laboratoire de Géologie de Lyon, Université Lyon 1, Ecole Normale Supérieure de Lyon, Université de Lyon, CNRS, 69100 Villeurbanne, France. nicolas.coltice@univ-lyon1.fr
Science (New York, N.Y.)
|April 21, 2012
まとめ
海底の年齢分布はプレート構造と大陸によって形成され,臨界年齢の沈下だけではありません. シミュレーションにより,過去の海底生産率は現在の2倍であったことが明らかになり,地球科学に影響を与えました.
科学分野:
- 地質物理学 地質物理学とは地質物理学です.
- 地球科学 地球科学 地球科学
- プレート・テクトニクス (プレート・テクトニクス)
背景:
- 海底の年齢分布は,海平面やマントルの熱損失などの地球上の重要な特徴に影響を与えます.
- 現在の海底年齢分布は,沈下のタイミングに関する熱コンベクション理論と矛盾しています.
研究 の 目的:
- 海底の面積年齢分布にプレートのような行動と大陸の影響を調査する.
- プレート境界の変動が時間の経過とともにこの分布にどのように影響するかを理解する.
主な方法:
- マントルのコンベクションの球形モデルを使用した.
- プレート境界の形成と破壊を含む,地球の構造的プロセスをシミュレートした.
主要な成果:
- プレートのような行動と大陸が,現在の地球を代表する海底の面積年齢分布を作り出すことを実証した.
- この分布がプレート境界の進化とともに動的に変化することを示した.
結論:
- マントルのコンベクションモデルは,海底の年齢分布を形作る上でプレート構造と大陸の役割を支持しています.
- 海底の生産率は,歴史的に現在の2倍のペースでピークに達しており,過去の大規模な構造的活動を示しています.
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