まとめ
1500メートル以下の深海水には,明確な炭素14レベルがあります. これらのレベルは,アビサルの海水が,世界中で約500年ごとに置き換えられていることを示しています.
科学分野:
- 海洋学 海洋学 海洋学
- 放射化学は放射化学である.
- 地質化学 地質化学
背景:
- 海洋循環の理解は,気候モデリングに不可欠です.
- 深海の水は,世界の炭素循環に重要な役割を果たしています.
- 炭素14は,水の質量移動と年齢を研究するための貴重なトレーサーです.
研究 の 目的:
- 底層の海洋水の補充率を決定する.
- 炭素14の分布を利用して深海水の年齢を推定する.
- 主要な海洋盆地における深水の補給時間を比較するために.
主な方法:
- 地下水のサンプルにおける炭素14濃度の分析.
- 水質の年齢を計算するための放射線年代測定法.
- 炭素14のデータを解釈するための地化学モデリング.
主要な成果:
- 太平洋の深い水域では,約510年の代替時間が示されています.
- インド洋の深海の水は,約250年の交換時間があります.
- 大西洋の深い水域は275年に1度交換される.
- 深い海の水の地球的な平均補給時間は500年を超えています.
結論:
- 深海の循環は,異なる盆地で異なる速度でゆっくりとしたプロセスです.
- 炭素14年代測定は,深淵の水質の居住時間について堅実な推定を提供します.
- この発見は,海洋の炭素吸収と輸送メカニズムをよりよく理解するのに役立ちます.
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