北大西洋の縁に沿った連続した深海塩層は,リフト形成の初期段階に関連しています
G Pautot1, J M Auzende, X Le Pichon
1Centre Océanologique de Bretagne, BP 337-29N, Brest.
Nature
|July 25, 1970
まとめ
深層地震調査は,複数の大西洋沿岸と地中海を横断する深海で,広範囲にわたるダイアピル構造を明らかにしています. これらの特徴は,初期の大陸裂けの段階に関連した連続した深海塩層を示唆しています.
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
- テクトニクス (地質学) とは
背景:
- メキシコ湾でよく見られるダイアピル状の構造は,様々な深海地域で観察されています.
- これらの構造の起源を理解することは,地域地質史の解読に極めて重要です.
研究 の 目的:
- ラブラドール,ニューファンドランド,モーリタニア,モロッコ,ポルトガル,スペイン,アイルランド,地中海沖の深海におけるダイアピル構造を特定し,特徴づけること.
- 連続した深海の塩層の存在の可能性と,大陸の裂け目との関連を調査する.
主な方法:
- 地表下の地質構造物の画像を撮るために,深い地震反射調査が採用されました.
主要な成果:
- ラブラドール,ニューファンドランド,モーリタニア,モロッコ,ポルトガル,スペイン,アイルランドの海岸沖の深海や地中海でダイアピル構造が確認されました.
- これらのダイアピルの形態学は,メキシコ湾で発見された塩のドームと類似しています.
結論:
- メキシコ湾の塩のドームとの広範な発生と類似性は,これらの大陸の縁で連続した深海塩層が存在することを示唆しています.
- この広大な塩層は,これらの地域における大陸分裂の初期段階からの遺物である可能性が高い.
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