岩石におけるコスモゲンクロリン-36の蓄積:表面曝露の年代測定のための方法
Science (New York, N.Y.)
|January 3, 1986
まとめ
岩石に塩素36の蓄積は,新しいジオクロノメーターを提供する. この方法は,火山岩や地形の表面被曝時間を測定し,1000年から100万年前の特徴を測定します.
科学分野:
- 地質化学 地質化学
- コスモジェニック・ヌクレイド・デッティング
- ジオクロノロジー (Geochronology) について
背景:
- 鉱物との宇宙線相互作用は,宇宙原核酸を生成する.
- 塩素36 (36Cl) は,地球表面の岩石に蓄積される.
- 安定塩化物 (Cl−) は,岩石における一般的な元素である.
研究 の 目的:
- ジオクロノメーターとして36Clと安定Clの比率を評価する.
- 若い火山岩と地形的な特徴の年代測定のために36Clを使用する可能性を決定する.
主な方法:
- 既知の年齢の火山岩の36Cl濃度を測定する.
- 岩の組成と宇宙線流量に基づいて予測された36Clの生成を計算した.
- 36Clと安定したClの比率を分析する.
主要な成果:
- 日付付付いた火山岩で測定された36Clと計算された生産量との間で良好な一致が見られました.
- 36Cl/Cl比は,信頼できるジオクロノメーターとしての可能性を示している.
- この方法は,表面曝露の年代測定に適用できます.
結論:
- 36Cl/Cl比は,表面曝露年代測定に有効なジオクロノメーターである.
- この方法により,若い火山岩や地形的な特徴の年代測定が可能です.
- 効果的な年代測定は103年から106年です.
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