地球で最も古いオフィオライトの残骸です
Harald Furnes1, Maarten de Wit, Hubert Staudigel
1Centre for Geobiology and Department of Earth Science, University of Bergen, Bergen, Norway. harald.furnes@geo.uib.no
Science (New York, N.Y.)
|March 24, 2007
まとめ
海底の広がりによって形成された最も古い海殻は,グリーンランドで発見された. このパレオアルケアンのイシュア・オフィオライト複合体は,初期の地球の証拠を提供します.
科学分野:
- 地質学 地質学 地質学
- パレオントロジー・パレオントロジー
- 海洋学 海洋学とは
背景:
- グリーンランド南西部のイシュア上皮帯 (ISB) には,地球上で最も古い岩石がいくつか含まれています.
- 初期の地球のプロセスを理解するには,保存状態が良好な古代地殻の残骸を調査する必要があります.
研究 の 目的:
- ISB内のシートダイク複合体の地質学的および地化学的特性を調査する.
- イサウオフィオライト複合体の起源と設定を決定する.
- 最古の海洋地殻増殖の証拠を提供するために.
主な方法:
- 板状の堤防と関連する枕の溶岩の地化学分析.
- 変形状態を推論するための酸素同位体分析.
- 関連するガブロイク岩とウルトラマフ岩の Petrological 検査.
主要な成果:
- この研究では,広がりによる海洋地殻の増殖を示すシートダイク複合体を特定しました.
- ジオケミストリーは,海内島の弧と中海の山脊のような設定を示唆しています.
- 酸素のイソトープは,水熱による海底変異を示している.
結論:
- イサウオフィオライト複合体は,海底の広がりによって形成された海洋地殻の最も古い知られている例を表しています.
- この発見は,初期の地球の構造的活動を支配するプロセスに関する重要な洞察を提供します.
- 板状の堤防は,最古の無傷の海洋地殻の残骸である.
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