GRIP氷核,グリーンランドにおける36Cl流の地磁気変調
1S. Baumgartner, J. Beer, J. Masarik, G. Wagner, Environmental Physics, Swiss Federal Institute of Science and Technology, CH-8600 Dubendorf, Switzerland. L. Meynadier, Laboratoire de Geochimie et Cosmochimie, CNRS 1758, Institut de Physique d.
Science (New York, N.Y.)
|March 11, 1998
まとめ
地磁場の強さは,宇宙的同位体生成に影響する. 塩素36の氷核データはこれを確認し,過去10万年の古磁気再構築と一致しています.
科学分野:
- 古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは
- 地質物理学 地質物理学とは地質物理学です.
- 宇宙化学 (コスモケミストリー)
背景:
- ベリリウム-10,炭素-14,塩素-36のような宇宙生成同位体は,地球の地磁場の変化に敏感である.
- これらの変化を理解することは,正確な古気候の再構築と年代測定に不可欠です.
研究 の 目的:
- 地磁場強度と宇宙的同位体生産率との関係を調査する.
- 氷の核から得られた塩素36のデータを用いて,古磁気復元を検証する.
主な方法:
- グリーンランド・アイス・コア・プロジェクト (GRIP) の氷芯サンプルにおける塩素36濃度の分析.
- クロール-36のデータと,過去10万年にわたる古磁気再構築に基づいた生産率の計算を比較する.
主要な成果:
- GRIPの氷芯から得られた塩素-36のデータは,長期的および短期的な地磁気変動を反映した計算された生産率と強く一致しています.
- 38000年前のヴォストークの氷の核ベリリウム10の記録で以前に確認された塩素-36のピークは,地磁場強度が低下した期間によって説明されています.
結論:
- 地磁場の強さは,宇宙的同位体生産に大きく影響する.
- 氷の核の同位体記録は,過去の地磁場行動と関連する気候の影響を再構築するための信頼できるプロキシを提供します.
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