中大西洋のの地殻の厚さ:ブルズアイ重力の異常と集中収縮の焦点
まとめ
ミッド・アトランティック・リッジの広がるセグメントは,地殻の厚さの変動による負の重力異常を示しています. 層3の変異によって引き起こされる,セグメントの中心部でのより厚い地殻と端のより薄い地殻は,これらの発見を説明します.
科学分野:
- 地質物理学 地質物理学とは地質物理学です.
- 海洋地質学 海洋地質学
- プレート・テクトニクス (プレート・テクトニクス)
背景:
- 中大西洋山脊の広がる部分は,マントル・ブーゲーの重力場におけるマイナスの標的の異常によって特徴付けられています.
- これらの重力異常の発生源を理解することは,地殻の構造と中海の山脊における蓄積過程の解釈に極めて重要です.
研究 の 目的:
- 中大西洋脊の部分に沿った負の重力異常の原因を調査する.
- 地震屈折データを用いて地殻の厚さの変動と重力の異常との関係を決定する.
主な方法:
- 地震屈折データ収集と分析,南極33度の中大西洋の山脊.
- 地殻の厚さや層3の変動に基づく重力異常のモデリング.
主要な成果:
- 負の重力異常は,広がるセグメントに沿った地殻の厚さの変動によって説明されます.
- 地殻の厚さは,セグメントの中心部でより大きく,セグメントの末端に向かって減少します.
- これらの厚さの変動は,主にレイヤ3の厚さの変化に起因する.
結論:
- 地殻の増殖は,このゆっくり広がるのセグメントに集中しています.
- 軸谷の深さは,底辺の地殻の厚さと直接関係しています.
- 軸に沿った密度の変動は,中海の山脊からの重力データを解釈する際に考慮する必要があります.
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