マール・トランティヴァリタティスとオセアヌス・プロセララムからの月の岩石のカリウム・アルゴン年代
Science (New York, N.Y.)
|October 9, 1970
まとめ
月のマリアは古くから存在し,異なる時期に形成されています. カリウムアルゴン年代測定により,Mare Tranquillitatisの岩石は38億年,Oceanus Procellarumの岩石は28億年,様々な地質学的歴史を示しています.
科学分野:
- 月面地質学 月面地質学
- 放射線年代測定法による年代測定
背景:
- 月面のマリアは,古代の火山噴火によって形成された広大で暗い平原です.
- 月のマリアの年齢と形成を理解することは,月の地質学史にとって極めて重要です.
研究 の 目的:
- Mare TranquillitatisとOceanus Procellarumから結晶岩の年齢を決定するために.
- 月面マリアの形成のタイミングと地質学的プロセスを調査する.
主な方法:
- 月の結晶岩のサンプルのカリウム-アルゴン年代測定.
- 地質的な衝撃と冷却速度の関係におけるアルゴン損失の分析.
主要な成果:
- Mare Tranquillitatisの岩は38億年前のカリウム-アルゴンの年代を示しています.
- Oceanus Procellarumの岩は,28億年前のカリウム-アルゴンの年代を示しています.
- Oceanus Procellarumの岩は,Mare Tranquillitatisの岩よりもはるかに多くのアルゴンの損失を示しました.
結論:
- 月マリアは古代の特徴であり,同時に形成されたものではありません.
- Oceanus Procellarumの岩石におけるアルゴンの大きな損失は,Mare Tranquillitatisと比較して,この地域でより深刻な衝撃効果またはより長い冷却速度を示唆しています.
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