ニュージーランドのフィオードランド地域での上昇: 初期潜水への影響
M A House1, M Gurnis, P J J Kamp
1Division of Geological and Planetary Sciences, Caltech, Pasadena, CA 91125, USA. mhouse@gps.caltech.edu
Science (New York, N.Y.)
|September 21, 2002
まとめ
ニュージーランド・フィオルドランドのケノゾイク期後半の脱皮は,沈殿開始時にプレート上昇を示しています. この研究は,熱クロノメトリーと重力データを用いて,潜流の始まりを日付付けています.
科学分野:
- 地質物理学 地質物理学とは地質物理学です.
- ジオクロノロジー (Geochronology) について
- テクトニクス (地質学) とは
背景:
- ニュージーランドのフィオルドランドには,地質学的な特徴があり,重要な構造学的な活動を示唆しています.
- 地域的なデヌデーションパターンを理解することは,地質学的なプロセスを解読する上で極めて重要です.
研究 の 目的:
- 低温サーモクロノメトリーを用いてフィオルドランドにおけるケノゾイク期末の脱毛を調査する.
- デヌデーションパターンを,サブデュークション開始のジオダイナミックモデルと相関させるため.
- 地殻の上昇と動的サポートのタイミングと範囲を決定する.
主な方法:
- 低温サーモクロノメトリーで,解剖と発掘の歴史を分析する.
- 地下構造を特定するために重力異常 (ブーガー重力) の分析.
- 熱クロノメトリックデータと地力学モデルの統合.
主要な成果:
- 紀元後期におけるフィオルドランドにおける地域脱水.
- 掘り出しの北向きの進行は,移動する潜水開始と結びついています.
- 最近の上昇とプラスのブーゲーの重力異常との相関.
- 地力学的な予測と一致する,約2kmのダイナミックサポートの証拠.
結論:
- この研究は,フィオルドランドに隣接する沈殿の開始の証拠を提供します.
- 熱クロノメトリックと重力学データは,プレート上昇のジオダイナミックモデルをサポートしています.
- この発見は,この地域での潜水噴出の始まりを年代付けするのに役立ちます.
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