ガラパゴス三重交差点にある逆回転マイクロプレート
Emily M Klein1, Deborah K Smith, Clare M Williams
1Nicholas School of the Environment and Earth Sciences, Duke University, Durham, North Carolina 27708-0227, USA. ek4@duke.edu
Nature
|February 25, 2005
まとめ
イースト・パシフィック・ライズ (East Pacific Rise) の東にある新しい裂け目が,ガラパゴス三重交差点にある2つの逆回転するマイクロプレートを明らかにしています. この発見は,この地域の構造板の移動に関する私たちの理解を新たに定義します.
科学分野:
- 地質物理学 地質物理学とは地質物理学です.
- プレート・テクトニクス (プレート・テクトニクス)
- 海洋地質学 海洋地質学
背景:
- ガラパゴスミクロプレート (Galapagos microplate) は,東赤道太平洋の重要な特徴である.
- "初期"の蔓延センターは,以前はその北の境界線として特定されていた.
- この広がりの中心は,ゆっくりと分岐し,西に広がる裂け目であると考えられていた.
研究 の 目的:
- "初期"の拡散センターの全範囲と動きを調査する.
- ガラパゴス三重交差点の複雑な構造相互作用を理解するために.
- 地域の追加のマイクロプレートを特定し,特徴づけること.
主な方法:
- 海底の広がりの特徴を特定するために,バチメトリックデータの分析.
- マイクロプレート運動を主要な構造プレートに相対的に決定するための運動モデリング.
- 裂け目の拡散と回転の地球物理学的解釈.
主要な成果:
- "初期"の拡散センターの東方への裂け目を示す証拠が提示されました.
- ガラパゴス微板の北に,逆時計方向に回転する第2の微板の特定.
- ガラパゴス三重関節は,ヘス・ディープ・リフトによって分離された2つの反回転するマイクロプレートによって特徴付けられています.
結論:
- "初期裂け目"は反時計方向に開き,第2のマイクロプレートに境界線を設ける.
- ガラパゴス三重交差点には,逆回転する2つのマイクロプレートが含まれています.
- マイクロプレート運動は,エッジドラッグによって駆動される硬いブロックとしてモデル化することができます.
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