海洋板の組成制御のためのMELT領域からの地質学的証拠
Rob L Evans1, Greg Hirth, Kiyoshi Baba
1Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543, USA. revans@whoi.edu
Nature
|September 9, 2005
まとめ
MELT実験は,東太平洋上昇の下の融解分布は,単に冷却ではなく,水分の減少によって影響されていることを明らかにしています. これは,海洋石層の初期の進化に影響を与える.
科学分野:
- 地質物理学 地質物理学とは地質物理学です.
- 海洋学 海洋学 海洋学
- 固体地球科学 固体地球科学
背景:
- 東太平洋上昇は,中洋のの過程を研究するための重要な場所です.
- 海洋石層の進化を理解するには,融解分布と物理的性質の知識が必要です.
研究 の 目的:
- 南部東太平洋上昇の下の融解の分布を制限するために.
- 海洋石層の初期の冷却の歴史と進化を調査する.
主な方法:
- MELT実験の磁気伝導学および地震学データを活用した.
- 分析した構造は,山頂の東方約100~350km (海底年齢1.3~4.5ミール) にあります.
主要な成果:
- 60kmの深さ以下では,電気伝導性の有意な増加が観察されました.
- イソトロピックから横断アニソトロピックな電気構造への移行が検出されました.
- 構造は,研究された地域において,年齢に大きく左右されないことが判明した.
結論:
- 融解による60km以上での水分量の減少は,若い海洋プレート構造を制御することを推論した.
- これは,導電式冷却モデルの予測とは対照的です.
- この発見は,海洋中部の山脊におけるマグマと水熱の過程についての洞察を提供します.
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