ルビジアム・ストロンチウム 月の物質の年代記と化学
Science (New York, N.Y.)
|January 30, 1970
まとめ
異なる2種類の火山岩の月岩が特定され,そのうちの1つは38億年前のものである. 月面の土壌とブレクシアは,化学的にこれらの岩の混合物を表しています.
科学分野:
- 地質学 地質学 地質学
- 惑星科学は惑星科学である.
- ジオクロノロジー (Geochronology) について
背景:
- 磁性月の岩は,異なる化学組成を示し,複数の起源を示唆しています.
- アイソクロン図は,岩の単位の年齢と遺伝的関係を決定する上で極めて重要です.
研究 の 目的:
- 磁性月の岩を化学的に特徴づけ,その年齢を決定する.
- 化学分析を通じて月の土壌とブレキアの起源を調査する.
主な方法:
- 月の岩石サンプルの化学分析.
- 鉱物と全岩のサンプルを用いたアイソクロン年代測定.
- ストロンチウムイソトープ比率分析.
主要な成果:
- 月の岩石の2つの異なる化学グループが特定されました.
- ミネラル・アイソクロンは,一つの岩の種類について,3.80 ± 0.11 億年の年齢を示した.
- 両岩の初期ストロンチウム-87/ストロンチウム-86の比率は約0.6994.6である.
- 月面の土壌とブレクシアは,化学的に2つの熱性土壌の混合物と似ており,さらに鉱物や微量元素の多様性がある.
結論:
- この2種類の火山岩は,それぞれ異なる地質学的単位を表している可能性が高い.
- 決定された38億年の年齢は,月の地質学史にとって重要である.
- 月面のレゴリット組成は,異なる岩石源の混合と,その後の変化によって影響を受けます.
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