SNC隕石の水:火星の水球の証拠
H R Karlsson1, R N Clayton, E K Gibson
1Planetary Science Branch, National Aeronautics and Space Administration, Johnson Space Center, Houston, TX 77058.
Science (New York, N.Y.)
|March 13, 1992
まとめ
火星の隕石 (SNC) で発見された水は,地球外のものである. 酸素同位体分析により,明確な貯水池が明らかになり,火星にはプレート構造が欠けている可能性が示唆されており,これは水と岩の組成を分離して維持する重要な要因である.
科学分野:
- 惑星科学は惑星科学である.
- 地質化学 地質化学
- 天体生物学 アストロバイオロジー
背景:
- シェルゴッティ・ナクラ・チャシグニー (SNC) 隕石は,火星から発生したと考えられています.
- これらの隕石には,かなりの量の水 (重量0.04-0.4%) が含まれています.
- この水の起源と性質を決定することは,火星の歴史を理解するために極めて重要です.
研究 の 目的:
- SNC隕石の中の水の起源を調査するために.
- 水が宿主岩と同位体均衡状態にあるかどうかを判断する.
- 主体,潜在的に火星の地質学的プロセスへの影響を推測する.
主な方法:
- SNC隕石内の水と宿主岩の酸素同位体分析.
- 地上の水と地外の水を区別するための同位体シグネチャの比較.
- 異なる惑星の貯水池間の同位体均衡の評価.
主要な成果:
- SNC隕石の水の一部は,地球外生命体であることが確認されました.
- この地球外生命体の水は,宿主岩と酸素同位素の均衡が崩れていることが判明しました.
- これは,2つの異なる酸素同位体貯蔵庫 (石層と水層) の形成を示しています.
結論:
- SNC隕石には,宿主岩と同位体相互作用していない地球外の水が含まれています.
- 異なる石層と水層の酸素同位体貯蔵庫の存在は,広範囲にわたる混合の欠如を示唆しています.
- 火星が母体である場合,この均衡の欠如はプレート構造の欠如に起因する可能性があります.
キーワード:
NASA Center JSCは,NASAセンターJSCが,NASAセンターJSCが,NASAセンターJSCが,NASAセンターJSCが,NASAセンターJSCが,NASAセンターJSCが,NASAセンターJSCが,NASAセンターJSCが,NASAセンターJSCが,NASAセンターJSCが,NASAセンターJSCが,NASAセンターJSCは,NASAセンターJSCが,NASAセンターJSCは,NASAセンターJSCは,NASAセンターJSCは,NASAセンターJSCは,NASAセンターJSCは,NASAセンターNASAの規律 エクゾバイオロジーNASAの規範52-10号についてNASA エクゾバイオロジープログラム
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